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Breast Cancer Awareness Month: Progress in Metastatic Breast Cancer Research & Treatment

October 30, 2025
ID
13572

Transcript

  • 00:01I'm doctor Miriam Lustberg,
  • 00:03and I'm joined today by
  • 00:05two colleagues
  • 00:07from the Yale Breast Program,
  • 00:10doctor Sarah Shellhorn
  • 00:12and doctor Dan O'Neil.
  • 00:14We are all breast oncologists,
  • 00:17and we will be focusing
  • 00:19on today
  • 00:20on all aspects of metastatic
  • 00:23breast cancer,
  • 00:24in terms of systemic therapies,
  • 00:27what are we currently using
  • 00:29in the clinic as well
  • 00:30as clinical trials as well
  • 00:32as some of the,
  • 00:34newer emerging,
  • 00:35therapies.
  • 00:37There will be ample time
  • 00:38for questions.
  • 00:39So as you think of
  • 00:40questions, feel free to
  • 00:42put them in the in
  • 00:44the q and a portion,
  • 00:46of the portal,
  • 00:47and we should have,
  • 00:50time to to get to
  • 00:51to most of your questions.
  • 00:54So,
  • 00:55so so the focus tonight,
  • 00:58is is, as I mentioned,
  • 00:59on metastatic breast cancer,
  • 01:01where the primary,
  • 01:04most effective therapy is a
  • 01:05systemic therapy. So we'll be
  • 01:07talking about the different subtypes
  • 01:09of breast cancer
  • 01:10and,
  • 01:11what the different
  • 01:13management strategies are.
  • 01:15With that, I will turn
  • 01:17it over to doctor Sarah
  • 01:18Schallhorn.
  • 01:21Thank you, Mariam, and welcome
  • 01:23to everybody. I'm delighted to
  • 01:25be here tonight. I just
  • 01:26took a quick peek over
  • 01:28at the attendee list, and
  • 01:29I see some familiar faces.
  • 01:31So for those of you
  • 01:32I know, welcome. And for
  • 01:33those of you that I
  • 01:34don't know,
  • 01:35welcome.
  • 01:37But,
  • 01:38doctor O'Neil and I have
  • 01:40divided up our time. We
  • 01:42were asked to prepare
  • 01:44ten to fifteen minutes of
  • 01:46of information about metastatic
  • 01:48breast cancer. And so we
  • 01:50divided that in into two
  • 01:52groups, and I'll be discussing
  • 01:53primarily
  • 01:55two subtypes of breast cancer,
  • 01:57HER2 positive and triple negative
  • 01:59metastatic breast cancer.
  • 02:01And doctor O'Neil will be
  • 02:02taking on the
  • 02:04the huge topic of hormone
  • 02:05receptor positive breast cancer.
  • 02:08And
  • 02:09this is easily
  • 02:11this this topic could easily
  • 02:13take up several hours.
  • 02:16We could we could wax
  • 02:17poetic for a really long
  • 02:19time.
  • 02:20So trying to condense this
  • 02:22to just ten to fifteen
  • 02:23minutes was a challenge.
  • 02:26But we we will give
  • 02:27it a try.
  • 02:28So very, very quickly, what
  • 02:31is metastatic breast cancer?
  • 02:33As many of you likely
  • 02:35know, it's cancer that started
  • 02:37in the breasts.
  • 02:38And and when cancer starts
  • 02:40in the breasts, it starts
  • 02:42to develop
  • 02:43two basic characteristics
  • 02:45that make cancer cancer.
  • 02:47One of them
  • 02:48is the ability to grow
  • 02:50without any
  • 03:03a
  • 03:06start to form cancer,
  • 03:08that stays within the breast
  • 03:10and stays within the lobes
  • 03:12or the ducts of the
  • 03:13breast.
  • 03:14Then they can become
  • 03:15invasive
  • 03:17and develop
  • 03:18into metastatic disease. When those
  • 03:20cancer cells invade, they break
  • 03:23through the lining of the
  • 03:24duct or the lobe,
  • 03:27and start to invade into
  • 03:29either the bloodstream or the
  • 03:31lymphatics
  • 03:32and travel to other parts
  • 03:34of the body.
  • 03:35So the definition of metastatic
  • 03:37breast cancer is
  • 03:38breast cancer cells that have
  • 03:40traveled to another part of
  • 03:42the body. And the most
  • 03:43common places for breast cancer
  • 03:45to go are the lung,
  • 03:47the liver, and the bones
  • 03:49with a fourth
  • 03:51most common location
  • 03:52being the brain.
  • 03:55And when we think about
  • 03:57how metastatic breast cancer is
  • 03:59treated,
  • 04:01we first look at
  • 04:03three different proteins. We look
  • 04:05at the estrogen receptor, the
  • 04:07progesterone
  • 04:08receptor, and a protein called
  • 04:10HER2,
  • 04:11on every breast cancer
  • 04:13specimen. So the pathologist
  • 04:15looks at a biopsy specimen,
  • 04:18looks at these cells under
  • 04:19the microscope, and measures the
  • 04:21amount
  • 04:22of estrogen receptor and progesterone
  • 04:24receptor and then a protein
  • 04:26called HER2. We'll talk about
  • 04:27it in a second.
  • 04:28And,
  • 04:30I'm I'm gonna leave a
  • 04:31little of this for doctor
  • 04:32O'Neil, but estrogen and progesterone
  • 04:34are female hormones
  • 04:36that even
  • 04:38after menopause are circulating in
  • 04:40in some level in the
  • 04:41bloodstream.
  • 04:42And the presence of the
  • 04:44estrogen receptor and presence of
  • 04:45the progesterone
  • 04:46receptor on a cancer cell
  • 04:49means
  • 04:50that that cancer cell is
  • 04:51fueled
  • 04:52at least in part
  • 04:54by those hormones. So cancers
  • 04:56that have the estrogen and
  • 04:58or progesterone receptor are hormone
  • 05:00receptor positive
  • 05:02and tend to respond to
  • 05:05anti hormone types of treatment.
  • 05:07So that's the sub the
  • 05:08subject of doctor O'Neil's
  • 05:10whole spiel, which we'll get
  • 05:11to in a second.
  • 05:14The the third protein that
  • 05:15we look for is a
  • 05:17protein called HER2.
  • 05:19And HER2 is a protein
  • 05:22that sits on the surface
  • 05:23of cancer cells,
  • 05:25and
  • 05:26it's there in low numbers
  • 05:28normally, but sometimes it can
  • 05:30be present in
  • 05:31in higher levels.
  • 05:34And when it's present in
  • 05:35higher levels, that can be
  • 05:37the driving force for cancer.
  • 05:39So lots of HER2
  • 05:41can make those cancer cells
  • 05:43want to grow faster,
  • 05:45and spread quicker.
  • 05:49And so,
  • 05:53the topic of my portion
  • 05:55of this program is is
  • 05:57HER2 positive breast cancers
  • 06:00and then another subtype
  • 06:03called triple negative breast cancer.
  • 06:05And so we talked about
  • 06:07the three different receptors that
  • 06:08we check, the estrogen receptor,
  • 06:10the progesterone receptor, and then
  • 06:12this protein called HER2. And
  • 06:14when the cancer cells do
  • 06:15not have any of those
  • 06:17three proteins, that's one, two,
  • 06:19three proteins that are negative,
  • 06:21it's where we get the
  • 06:22title or the name triple
  • 06:24negative breast cancer.
  • 06:26So I'm gonna first start
  • 06:27with triple negative breast cancer.
  • 06:31These aren't cancers that are
  • 06:32fueled by
  • 06:34hormones. They are not
  • 06:36fueled by having extra amounts
  • 06:38of HER2.
  • 06:39And, unfortunately,
  • 06:41that means that the mainstay
  • 06:43of treatment
  • 06:44is chemotherapy
  • 06:45drugs.
  • 06:46And these are chemotherapy drugs
  • 06:47that are generally given through,
  • 06:50through the vein in an
  • 06:51intravenous fashion.
  • 06:53And these drugs go everywhere
  • 06:55in the body
  • 06:56with the idea of trying
  • 06:58to kill cancer cells wherever
  • 07:00they might be. And we
  • 07:02have lots and lots of
  • 07:03chemo drugs that work in
  • 07:05breast cancer and in in
  • 07:06triple negative breast cancer,
  • 07:10but they have lots of
  • 07:11side effects. This is one
  • 07:12of the big problems with
  • 07:13chemotherapy. It can affect almost
  • 07:15every organ system in the
  • 07:17body from the brain all
  • 07:19the way to the muscles,
  • 07:20from the lungs to the
  • 07:22genitourinary
  • 07:23system.
  • 07:24Any part of the body
  • 07:26can be affected by by
  • 07:27chemotherapy
  • 07:28because it's not particularly specific.
  • 07:31It doesn't
  • 07:32target anything.
  • 07:34It really affects any cell
  • 07:36that's growing,
  • 07:38and that can be normal
  • 07:39cells like the lining of
  • 07:40the gut,
  • 07:41normal cells like they're in
  • 07:43the skin,
  • 07:45normal cells anywhere.
  • 07:48Furthermore, chemotherapy has even more
  • 07:51downsides. It's inconvenient.
  • 07:53It requires frequent visits to
  • 07:55clinic and to infusion.
  • 07:57This can impact things,
  • 07:59that are really important in
  • 08:01a woman's life, like
  • 08:03child care, trying to arrange
  • 08:05transportation.
  • 08:07These drugs are generally intravenous,
  • 08:09which means that that
  • 08:11getting an IV over time
  • 08:13can be more and more
  • 08:14challenging. Because every time you
  • 08:16put an IV in, you
  • 08:17create a little bit of
  • 08:18scar tissue.
  • 08:20It can lead to loss
  • 08:21of work productivity, which can
  • 08:23cause what we call financial
  • 08:24toxicity or financial harm to
  • 08:27people who have to deal
  • 08:28with chemotherapy over the long
  • 08:29term. And it can have
  • 08:31tremendous effects on on a
  • 08:32woman's mental health.
  • 08:34In fact, this is work
  • 08:36that I did a number
  • 08:37of years ago.
  • 08:39Not just physical concerns,
  • 08:41impact people,
  • 08:43getting
  • 08:44getting chemotherapy. And when we
  • 08:46showed that almost half of
  • 08:47patients or over half of
  • 08:48patients have more concerns with
  • 08:50things that aren't physical.
  • 08:55So I apologize if this
  • 08:57feels a little bit choppy
  • 08:58because it is. There's just
  • 08:59a lot to say here.
  • 09:01Some of the most exciting,
  • 09:04drugs that we're using now
  • 09:06belong to a class of
  • 09:08medicines called antibody drug conjugates.
  • 09:11So we talked a little
  • 09:12bit about the fact that
  • 09:13chemotherapy
  • 09:14is,
  • 09:17it targets
  • 09:19all different types of cells
  • 09:20regardless of where they are.
  • 09:22But antibody drug conjugates,
  • 09:24I'd like to think of
  • 09:25them more like tumor seeking
  • 09:27missiles.
  • 09:28So there's been a lot
  • 09:29of talk about antibodies over
  • 09:30the last five years since
  • 09:31the the start of the
  • 09:32COVID pandemic, but antibodies
  • 09:36are proteins
  • 09:37created by
  • 09:39by lymphocytes
  • 09:40in part of the immune
  • 09:42system.
  • 09:43But we can create
  • 09:45antibodies in the lab. These
  • 09:47are called monoclonal antibodies, and
  • 09:48they they basically are like
  • 09:50targets for particular proteins. So
  • 09:52you have an antibody to
  • 09:53a particular
  • 09:54protein.
  • 09:55And so
  • 09:58what an antibody drug conjugate
  • 10:00is
  • 10:01is an antibody that's targeting
  • 10:03a protein
  • 10:04on the cancer cell. And
  • 10:06riding along with it, attached
  • 10:08to the antibody,
  • 10:10is a chemotherapy drug. We
  • 10:12call that the payload.
  • 10:14The chemotherapy drug is riding
  • 10:15along with the antibody. So
  • 10:16the antibody finds the tumor.
  • 10:18It finds the protein that
  • 10:20it's looking for. It binds
  • 10:21to that protein, and it
  • 10:22delivers
  • 10:24the chemotherapy
  • 10:25directly to the tumor. And
  • 10:27there are a few different
  • 10:28antibody drug conjugates that have
  • 10:30come come about over the
  • 10:31last five, ten years, and
  • 10:33we'll talk about
  • 10:35most of them here.
  • 10:37The second class of medicines
  • 10:39that's used in triple negative
  • 10:41breast cancer
  • 10:43is immunotherapy.
  • 10:44And immunotherapy,
  • 10:47targets
  • 10:48the
  • 10:49immune system. And more
  • 10:51appropriately, it actually takes the
  • 10:53brakes off the immune system.
  • 10:55So in the presence of
  • 10:56cancer,
  • 10:58the immune system kinda says,
  • 10:59well, that that looks a
  • 11:01little bit like me. It
  • 11:02looks a little bit like
  • 11:03self.
  • 11:04I'm gonna back off.
  • 11:06So the cancer cell kind
  • 11:07of
  • 11:08puts the brakes on the
  • 11:09immune system, not allowing the
  • 11:11immune system to fight the
  • 11:12cancer.
  • 11:13But immunotherapies
  • 11:15like Keytruda,
  • 11:17probably the one we use
  • 11:18most commonly in breast cancer,
  • 11:20but there are others used
  • 11:21in other types of cancers,
  • 11:24works to take the brakes
  • 11:25off the immune system. So
  • 11:27it allows,
  • 11:29a person's a patient's body,
  • 11:31a patient's own immune system
  • 11:33to help fight the cancer.
  • 11:34And that reactivates the immune
  • 11:36system so that in combination
  • 11:39with chemotherapy,
  • 11:41the the immune system can
  • 11:43then fight the cancer and
  • 11:45get a more robust response.
  • 11:47So immunotherapy
  • 11:49is another class of medicines
  • 11:50that we use primarily in
  • 11:52triple negative breast cancer.
  • 11:54And finally,
  • 11:56another target that's that's applicable
  • 11:59for
  • 12:00several
  • 12:01types of breast cancer, but
  • 12:02those particularly
  • 12:04associated with BRCA one and
  • 12:07BRCA
  • 12:08two mutations.
  • 12:10These are called PARP inhibitors.
  • 12:12And it has to do
  • 12:13PARP inhibitors have to do
  • 12:15with
  • 12:16normal cell division. And and
  • 12:19people who have these types
  • 12:21of mutations
  • 12:22in in BRCA one and
  • 12:23BRCA two,
  • 12:26in the normal process of
  • 12:28cell division,
  • 12:30they make mistakes.
  • 12:32They make more mistakes than
  • 12:33than
  • 12:34is usual. And when those
  • 12:36mistakes happen in the normal
  • 12:37process of cell division,
  • 12:39cancers are much more likely.
  • 12:43The the
  • 12:45PARP inhibitor,
  • 12:47well, actually, people with these
  • 12:48mutations aren't able to
  • 12:51repair those mistakes in as
  • 12:53an efficient way as someone
  • 12:55who who doesn't have those
  • 12:56mutations. And PARP inhibitors
  • 12:59work,
  • 13:00by preventing
  • 13:02repair
  • 13:03and
  • 13:04basically lead these cells to
  • 13:05commit suicide. So PARP inhibitors
  • 13:07are pills that we use
  • 13:09fairly frequently in people that
  • 13:10have these types of mutations.
  • 13:13So moving very quickly to
  • 13:16HER2 positive breast cancer.
  • 13:18So remember, HER2 is a
  • 13:20protein that's on the surface
  • 13:22of cancer cells. And when
  • 13:23HER2 is there in high
  • 13:24levels or it's overexpressed,
  • 13:27that leads that's the the
  • 13:29primary driver for growth of
  • 13:31those cancer cells.
  • 13:34And up until maybe twenty
  • 13:36five ish years ago, this
  • 13:38was really bad because HER2
  • 13:41positive breast cancers,
  • 13:43were very aggressive. They had
  • 13:45high high likelihood of developing
  • 13:47into metastatic disease and high
  • 13:49likelihoods of going to going
  • 13:51to
  • 13:52major organs like the liver
  • 13:54and the brain.
  • 13:56But at again, about two
  • 13:58and a half decades ago,
  • 14:00the drug trastuzumab
  • 14:02or Herceptin was developed, and
  • 14:04it revolutionized the treatment of
  • 14:06of metastatic breast cancer first
  • 14:08and and then earlier stage
  • 14:10breast cancers a little bit
  • 14:11later.
  • 14:13And that began,
  • 14:15a long history of targeting
  • 14:18HER2,
  • 14:19first with trastuzumab
  • 14:21and then later with additional
  • 14:24antibody drug conjugates, other monoclonal
  • 14:26antibodies, and
  • 14:28oral medications called tyrosine kinase
  • 14:31inhibitors.
  • 14:32This is just the history
  • 14:33of HER2 positive breast cancer
  • 14:36way back to nineteen thirty
  • 14:38five, and not a whole
  • 14:39lot happened between nineteen thirty
  • 14:41five until nineteen until the
  • 14:43nineteen nineties. But starting in
  • 14:45nineteen ninety eight when trastuzumab
  • 14:47came about,
  • 14:48there have been
  • 14:49many, many drugs that have
  • 14:51been approved in various settings.
  • 14:54Lapatinib, pertuzumab,
  • 14:56a drug called TDM one
  • 14:57or Kadcyla,
  • 14:59neratinib or new NERLYNX,
  • 15:02pirotinib,
  • 15:03tucatinib, neratinib, margetuximab,
  • 15:05all of these drugs have
  • 15:06come about over just the
  • 15:08last decade or so,
  • 15:10in
  • 15:11for patients with HER2 positive
  • 15:13breast cancer. So really quickly,
  • 15:17HER2 positive
  • 15:20breast cancer is primarily treated
  • 15:22first with HER2 antibodies,
  • 15:25primarily trastuzumab and pertuzumab, which
  • 15:27target that HER2 receptor. And
  • 15:29these can be administered either
  • 15:31via infusion or a shot.
  • 15:35And they're often used together
  • 15:37because they block HER2
  • 15:39in in complementary ways.
  • 15:41Then there are oral HER2
  • 15:42drugs like lapatinib,
  • 15:44neratinib, tucatinib.
  • 15:46Sometimes I wonder who actually
  • 15:48names these medications. There's a
  • 15:49lot of vowels there. These
  • 15:50are hard to
  • 15:51say.
  • 15:53But these medications
  • 15:55block the intracellular
  • 15:57signaling that comes from the
  • 15:59HER2 receptor
  • 16:00leading to cell growth.
  • 16:01And then finally,
  • 16:03antibody drug conjugates,
  • 16:05the tumor targeting
  • 16:07missiles.
  • 16:08They have a a place
  • 16:10in
  • 16:11the treatment of HER2 positive
  • 16:13breast cancer too. In fact,
  • 16:15the two most common,
  • 16:17antibody drug conjugates
  • 16:19are HER2 targeting antibody drug
  • 16:21conjugates.
  • 16:24The the latest
  • 16:25antibody drug conjugate to come
  • 16:27through the pipeline is a
  • 16:28drug called nHER2,
  • 16:30which is trastuzumab
  • 16:32antibody
  • 16:33targeting HER2
  • 16:35coupled
  • 16:36with a a chemotherapy
  • 16:38called Dirextican.
  • 16:41Another antibody drug conjugate called
  • 16:44Kadcyla or trastuzumab
  • 16:47tansine is that Herceptin antibody
  • 16:50coupled to,
  • 16:52a chemotherapy called m tansine.
  • 16:55And
  • 16:56these two drugs have not
  • 16:58only,
  • 17:00provided us with two additional
  • 17:01treatments
  • 17:05data coming out just in
  • 17:08June of this year looking
  • 17:10at,
  • 17:11trastuzumab, daroxetacaner,
  • 17:13and HER2
  • 17:14in the first line setting
  • 17:16for people with metastatic HER2
  • 17:17positive breast cancer.
  • 17:20Occasionally, we we also use
  • 17:23chemotherapy
  • 17:24in HER2 positive disease,
  • 17:27combined with trastuzumab.
  • 17:30And then for patients that
  • 17:32have HER2 positive and also
  • 17:34hormone receptor positive breast cancer,
  • 17:36we also use endocrine therapy.
  • 17:40I'm I know I've already
  • 17:41gone over the time that
  • 17:43I said that I would
  • 17:43take,
  • 17:45but I wanna just mention
  • 17:48the way that new drugs
  • 17:51come up and they get
  • 17:53approved by the FDA is
  • 17:55through a series of clinical
  • 17:57trials.
  • 17:58And clinical trials
  • 18:00require patients. This is how
  • 18:02we determine
  • 18:03whether a drug is effective
  • 18:05or not, and we look
  • 18:06at new combinations of drugs
  • 18:07and compare them to to
  • 18:09older combinations. It's how we
  • 18:11move the field forward.
  • 18:13Clinical
  • 18:14trials, could also be called
  • 18:15clinical studies, studies, research trials,
  • 18:18protocols.
  • 18:20But a clinical trial
  • 18:23is,
  • 18:24more than just
  • 18:26a lab test or a
  • 18:27test on a guinea pig.
  • 18:29Clinical
  • 18:30clinical trials,
  • 18:32afford patients an opportunity
  • 18:34to contribute to the field
  • 18:36and potentially get highly effective
  • 18:38therapy even before it's approved.
  • 18:41There are lots of phases
  • 18:42of clinical trials starting at
  • 18:44the earliest phases where we're
  • 18:46we're studying new drugs or
  • 18:47new combinations of drugs and
  • 18:49looking
  • 18:50at at toxicities
  • 18:51all the way to phase
  • 18:53three clinical trials, which are
  • 18:55are usually
  • 18:56randomized
  • 18:57clinical trials where there are
  • 18:58multiple arms,
  • 19:01of the trial,
  • 19:03and even phase four clinical
  • 19:05trials, which which happen
  • 19:07after a drug is approved.
  • 19:13And the the likelihood
  • 19:14that a drug becomes FDA
  • 19:16approved
  • 19:17go gets lower and lower
  • 19:18the the later the phase
  • 19:19of the trial.
  • 19:22That is all that I
  • 19:24had prepared
  • 19:25for triple negative breast cancer
  • 19:27and HER2 positive disease.
  • 19:29But I'd love
  • 19:31to turn the
  • 19:33proverbial microphone over to Dan
  • 19:35O'Neil,
  • 19:36my colleague who is also
  • 19:38a practicing breast medical oncologist
  • 19:40to talk about
  • 19:41hormone receptor positive breast cancer.
  • 19:43And I will stop sharing
  • 19:45and turn it over to
  • 19:47you, doctor O'Neil.
  • 19:57I'm told I'm muted. Okay.
  • 20:00Thank you.
  • 20:01Thank you to doctor Schallhorn
  • 20:02for for doing the,
  • 20:05the impressive work of of
  • 20:06laying a lot of the
  • 20:07groundwork about,
  • 20:08you know, what metastatic breast
  • 20:10cancer is and and the
  • 20:12different types of metastatic breast
  • 20:13cancer.
  • 20:15I'm gonna be talking about
  • 20:16hormone receptor positive breast cancer,
  • 20:18and, you know, specifically hormone
  • 20:19receptor positive HER2 negative breast
  • 20:21cancer where we don't have
  • 20:22overexpression of that HER2 protein.
  • 20:25And just like Doctor. Shellhorn
  • 20:26described,
  • 20:28hormone receptor positive breast cancer
  • 20:30is breast cancer that has
  • 20:31expression of that estrogen receptor
  • 20:33and or that progesterone receptor
  • 20:36and is usually primarily driven
  • 20:37by the estrogen and progesterone,
  • 20:40hormones that, that that women
  • 20:42are making, you you know,
  • 20:44really over their entire lives,
  • 20:46to some amount, and, and
  • 20:48that you see circulating in
  • 20:50the blood in a in
  • 20:51a healthy woman. There have
  • 20:53been a lot of updates
  • 20:55in this in this space.
  • 20:56I gave a similar talk
  • 20:57about two years ago, and
  • 20:58and when I went back
  • 20:59to my slides, for for
  • 21:00today's talk, I had to
  • 21:01make a lot of updates.
  • 21:02So so that's really good
  • 21:04news.
  • 21:04I'm gonna talk about about
  • 21:06a lot of, specific drugs
  • 21:07that we're we're using, and
  • 21:09and how we sequence those.
  • 21:11So, to start out thinking
  • 21:13about the first line setting
  • 21:14or the initial therapies,
  • 21:17that a woman is likely
  • 21:18to receive for, a new,
  • 21:21or metastatic hormone receptor positive
  • 21:24breast cancer,
  • 21:25the standard there has remained
  • 21:27the same for for some
  • 21:28time
  • 21:29now. The standard, therapy is
  • 21:31a combination of a couple
  • 21:32of different, types of drugs.
  • 21:35The first type of drugs
  • 21:36are are kind of,
  • 21:38essential
  • 21:39anti estrogen backbones,
  • 21:41either aromatase inhibitors usually, which
  • 21:43are an oral medication or,
  • 21:45a injectable medication called fulvestrant.
  • 21:49And those two medications have
  • 21:51been around for a long,
  • 21:51long time.
  • 21:53But, within the last several
  • 21:54years,
  • 21:55a a newer type of
  • 21:56medication, a CDK four six
  • 21:58inhibitor has been incorporated into
  • 22:00into the treatment,
  • 22:01combination as well. So CDK
  • 22:03four six inhibitors are drugs
  • 22:05that,
  • 22:07inhibit a pathway,
  • 22:08that is part of the
  • 22:10process
  • 22:11that stands between,
  • 22:13the estrogen receptor and the
  • 22:15cell telling the cell to
  • 22:16divide,
  • 22:17in response to estrogen.
  • 22:19So these CDK four six
  • 22:20inhibitors interfere with that with
  • 22:22that signaling, with that communication,
  • 22:24and they help the,
  • 22:26endocrine therapies, the anti estrogen
  • 22:28therapies work for longer than
  • 22:30they would all on their
  • 22:31own.
  • 22:32There are three different CDK
  • 22:34four six inhibitors, that are
  • 22:36available on the market. They're
  • 22:37palbociclib
  • 22:38or Ibrance, bemaciclib
  • 22:39or Verzenio,
  • 22:41and ribociclib
  • 22:42or Kisqali.
  • 22:44And in in the clinical
  • 22:46trials looking at how long
  • 22:48they improved,
  • 22:49the time that a cancer
  • 22:50was controlled in that first
  • 22:52line setting,
  • 22:53the the results were pretty
  • 22:55similar.
  • 22:56The average amount of time
  • 22:56that a cancer could be
  • 22:57controlled with these,
  • 22:59these two drugs together
  • 23:01was around two years or
  • 23:02a little bit longer than
  • 23:03two years, and that was
  • 23:04that was consistent across all
  • 23:06three drugs.
  • 23:08In addition to that, there
  • 23:09have been studies that look
  • 23:10at how long overall life
  • 23:12expectancy,
  • 23:13is improved by by using
  • 23:14these medications early on.
  • 23:16And there there there are
  • 23:18maybe some differences that have
  • 23:19emerged,
  • 23:20in in what we call
  • 23:21real world trials or trials
  • 23:23looking at patients, you know,
  • 23:24actually out in the clinic
  • 23:25receiving the drugs.
  • 23:26There was suggestion that that
  • 23:28all three drugs improved,
  • 23:30life expectancy.
  • 23:32In the in the kind
  • 23:33of well controlled clinical trials,
  • 23:36that led to the approval
  • 23:37of these drugs, ribociclib
  • 23:39was probably the best performing,
  • 23:41increasing life expectancy by about
  • 23:42it by about a year.
  • 23:46So that's the first line
  • 23:48setting. That's been stable. A
  • 23:49lot of the the newer
  • 23:50approaches and newer medications,
  • 23:53really start to crop up
  • 23:54in the, second line setting
  • 23:56in in one situation and
  • 23:57first line setting that I'll
  • 23:58that I'll describe.
  • 24:01When you're looking at,
  • 24:03the next therapy, when when
  • 24:04the cancer is no longer
  • 24:05well, well controlled with those
  • 24:07first drugs,
  • 24:08something that's really important sort
  • 24:10of thematically is to think
  • 24:12about targetable
  • 24:13mutations and how those play
  • 24:14into, treatment selection.
  • 24:17So, to sort of explain
  • 24:18that,
  • 24:20when,
  • 24:21as the cancer is growing
  • 24:23and becomes metastatic or, or
  • 24:25continues to grow despite,
  • 24:27despite medications,
  • 24:29it's undergoing,
  • 24:30sometimes undergoing genetic changes and
  • 24:32developing,
  • 24:33specific mutations.
  • 24:35And in some cases, these
  • 24:36mutations have drugs that, that
  • 24:38are linked, drugs that, target
  • 24:40those mutations effectively and can
  • 24:41be particularly effective in those
  • 24:43cancer
  • 24:44types. But you need to
  • 24:45have genetic testing to identify
  • 24:46those mutations.
  • 24:49Importantly,
  • 24:50this sort of, the mutations
  • 24:52I'm referring to refer to
  • 24:53the mutations in the cancer
  • 24:54cells. They're different from the
  • 24:56mutations,
  • 24:57that are in the healthy
  • 24:58cells of, you know, a
  • 24:59woman's body that might have
  • 25:00been inherited by a family
  • 25:01member.
  • 25:02So this sort of genetic
  • 25:04testing is different from the
  • 25:05genetic testing that that many
  • 25:06women undergo when they're first
  • 25:07diagnosed, with with a breast
  • 25:09cancer,
  • 25:10be it metastatic
  • 25:12or not metastatic.
  • 25:14And it really includes testing
  • 25:15the tumor tissue itself.
  • 25:17As I mentioned, the mutations
  • 25:18can guide treatment selection.
  • 25:20And this testing can be
  • 25:22performed in a few different
  • 25:23ways. The most straightforward way
  • 25:25probably is directly testing the
  • 25:27tumor tissue itself. And that
  • 25:29would require a biopsy of
  • 25:30the tissue so that there
  • 25:32was, you know, some tissue
  • 25:33available for testing.
  • 25:35Alternatively, sometimes you can do
  • 25:37testing just on, using a
  • 25:39simple blood draw.
  • 25:40In that case,
  • 25:42what's called circulating tumor DNA
  • 25:43or DNA that's in the
  • 25:45blood that's been shed by
  • 25:46the cancer,
  • 25:47can be isolated and tested
  • 25:49for mutations.
  • 25:51And
  • 25:52an important thing to also
  • 25:54keep in mind is that,
  • 25:55as I sort of described
  • 25:57a little bit already, these
  • 25:58mutations do have, a tendency
  • 26:00to develop and to change
  • 26:01over time.
  • 26:02So, each time,
  • 26:04a new treatment is being
  • 26:05considered,
  • 26:06it can sometimes be helpful
  • 26:08to, to repeat testing.
  • 26:11So, I said there was
  • 26:13a circumstance
  • 26:14for initial therapy where,
  • 26:16where identifying a targetable mutation
  • 26:18can be helpful.
  • 26:20And, I'm going to describe
  • 26:21that. So,
  • 26:23this is a relatively new
  • 26:24approach.
  • 26:26The specific circumstance I'm referring
  • 26:28to are for breast cancers
  • 26:29that meet two criteria.
  • 26:32The first
  • 26:33criteria
  • 26:34is that the breast cancer
  • 26:35recurred
  • 26:37while a woman was taking
  • 26:38what's called adjuvant endocrine therapy
  • 26:40or kind of preventative,
  • 26:42anti estrogen therapy,
  • 26:44while she was in remission
  • 26:45from
  • 26:46her early stage breast cancer,
  • 26:48or the breast cancer recurred,
  • 26:50within a year of finishing
  • 26:51adjuvant endocrine therapy. And then
  • 26:53in addition to that, the,
  • 26:55breast cancer needs to have
  • 26:56a, a PIK3CA
  • 26:57mutation.
  • 27:00When those two criteria are
  • 27:02met,
  • 27:02there is a new,
  • 27:04combination of three drugs that
  • 27:06can sometimes be helpful for,
  • 27:06first line treatment for that
  • 27:06initial treatment. And those three
  • 27:06drugs are fulvestrant,
  • 27:08treatment for that initial treatment.
  • 27:10And those three drugs are
  • 27:11fulvestrant,
  • 27:12the older,
  • 27:14endocrine therapy, I described earlier.
  • 27:17Palbociclib,
  • 27:18one of the CDK4six
  • 27:20inhibitors from that first slide.
  • 27:22And then a new medication
  • 27:23called
  • 27:24Involisib,
  • 27:25which is a PI3 kinase
  • 27:28inhibitor pill. It's an oral
  • 27:29drug that targets this PIK3CA
  • 27:31mutation.
  • 27:34The advantage of this triple
  • 27:36combination,
  • 27:37therapy is that it works
  • 27:38to control cancer for longer
  • 27:40than just fulvestrant and poblociclib
  • 27:43by themselves.
  • 27:44So, it can control cancer
  • 27:46in about sixty percent of
  • 27:47women as compared to, just
  • 27:49about a quarter of women,
  • 27:50with that set of circumstances
  • 27:52I described,
  • 27:54when you're using just those
  • 27:55two drugs.
  • 27:57In addition to,
  • 27:59controlling cancer in more women,
  • 28:00it also controls cancer for
  • 28:02longer, typically
  • 28:07it seems to work considerably
  • 28:09better than the old,
  • 28:11two pair of medications.
  • 28:13A tricky thing about these
  • 28:15combinations of multiple drugs is
  • 28:17that as you add more
  • 28:19drugs, you do often see
  • 28:20more side effects and that
  • 28:22can be a challenge.
  • 28:24And that was indeed the
  • 28:25case with these medications.
  • 28:27So side effects
  • 28:28that are common with these
  • 28:30three drugs together
  • 28:31include diarrhea, mouth sores, and
  • 28:33sometimes high blood sugar levels.
  • 28:35So, just as important as
  • 28:37finding the right,
  • 28:38cancer treatment,
  • 28:40the other thing you have
  • 28:41to do with your oncologist
  • 28:42and that we spend a
  • 28:44lot of time doing is
  • 28:45working together on trying to
  • 28:46control side effects.
  • 28:49Okay. So, moving on to
  • 28:50the to the,
  • 28:51second treatment.
  • 28:55The,
  • 28:57or moving on to the
  • 28:58second line therapy, excuse me.
  • 29:01For a long time after,
  • 29:03that,
  • 29:04aromatase inhibitor,
  • 29:06treatment stops working in the
  • 29:07in the first line setting,
  • 29:09the standard approach was to
  • 29:10move on to this, fulvestrant
  • 29:11medication.
  • 29:12Fulvestrant is an intramuscular injection
  • 29:15that you have to receive
  • 29:16every four weeks, which is,
  • 29:19is not necessarily
  • 29:20a pleasant treatment to be
  • 29:21receiving.
  • 29:23And,
  • 29:24on its own, its response
  • 29:26time or the response,
  • 29:28time of the cancer is
  • 29:29not always as long as
  • 29:31we would hope.
  • 29:32And so, there have been
  • 29:33a number of,
  • 29:35different options,
  • 29:36that have been developed recently
  • 29:37to try and improve on
  • 29:39those outcomes,
  • 29:40and to improve on the
  • 29:41just the experience of receiving
  • 29:43the drug.
  • 29:45So, the first options I'll
  • 29:46go through are drugs that
  • 29:48target the ESR1 mutation.
  • 29:51The first of those is
  • 29:52a medication called
  • 29:54Elisestrin. Elisestrin has been on
  • 29:55the market for about two
  • 29:56years now.
  • 29:58It's a pill. It's not
  • 29:59an injection. It's a pill
  • 30:00that has the same mechanism
  • 30:02as fulvestrin. It's what was
  • 30:03called a selective estrogen receptor
  • 30:05degrader.
  • 30:08And, compared to fulvestrant in
  • 30:10women who have an ESR1
  • 30:11mutation,
  • 30:13it controls cancer longer. So,
  • 30:15it works better than fulvestrant
  • 30:16in addition to being an
  • 30:17oral medication for women with
  • 30:19an ESR1 mutation.
  • 30:21It seems to work best
  • 30:22and really that extra benefit
  • 30:24is mostly seen in women
  • 30:25who have, were able,
  • 30:27whose cancer was controlled for
  • 30:28at least twelve months, on
  • 30:30their first line anti estrogen
  • 30:32therapy.
  • 30:33So those are women who,
  • 30:34you know, it seems like
  • 30:35their cancer is still sensitive
  • 30:37to anti estrogen therapies.
  • 30:39And it can have some
  • 30:41side effects, but usually they're
  • 30:42not particularly,
  • 30:43difficult. It can have a
  • 30:45variety of GI side effects.
  • 30:46And can have some of
  • 30:47the same sort of anti
  • 30:48estrogen menopause type side effects
  • 30:50that you see with other
  • 30:51anti estrogen medications.
  • 30:54There is a,
  • 30:56practically brand new option,
  • 30:59for women with ESR one
  • 31:01mutations, that is is similar
  • 31:02in some ways to elocestrant.
  • 31:04It's called, illumin illuminestrant.
  • 31:07Also a lot of vowels
  • 31:08in that one.
  • 31:09It is also an oral
  • 31:11SIRD, just like the elocestrant.
  • 31:14And, just like elacestrant,
  • 31:17it controls cancer for longer
  • 31:19than fulvestrant amongst women with
  • 31:20ESRO mutations.
  • 31:22What makes it a little
  • 31:23bit different is that in
  • 31:25the
  • 31:26trial that led to its
  • 31:27approval,
  • 31:28there was a a third
  • 31:29group of women who received,
  • 31:32the, in luminescent in combination
  • 31:34with the bemiciclib.
  • 31:35And in that group of
  • 31:36women,
  • 31:37the amount of time the
  • 31:39cancer
  • 31:39even longer than with either
  • 31:41of the the single agent
  • 31:43drugs.
  • 31:44That use has not been
  • 31:45fully reviewed and approved by
  • 31:47the FDA yet, but it's
  • 31:48something that that might be,
  • 31:51might have potential in the
  • 31:52future.
  • 31:53And as I mentioned, this
  • 31:54drug was just approved by
  • 31:55the FDA towards the end
  • 31:56of September. So it's it's,
  • 31:57just kind of coming,
  • 31:59it's just becoming widely available.
  • 32:05The,
  • 32:09in addition to those oral
  • 32:10sird,
  • 32:11there's a there are some
  • 32:12other types of medications, some
  • 32:14other some medications with alternative
  • 32:16mechanisms of action,
  • 32:18for women with the ESR
  • 32:19one mutation.
  • 32:20One example of that is
  • 32:21a medication called veptigestrin.
  • 32:24It is a pill with
  • 32:25a, with a slightly different,
  • 32:27sort of,
  • 32:28mechanism for
  • 32:30destroying or degrading the estrogen
  • 32:32receptor.
  • 32:33It also increases time on,
  • 32:36of control
  • 32:37of the cancer and when
  • 32:38with ESR1 mutations.
  • 32:40This has been studied and,
  • 32:42these results have been, shared
  • 32:44with, the scientific community, but
  • 32:46it hasn't been approved by
  • 32:47the FDA yet. It's under
  • 32:48review. So, potentially sometime in
  • 32:50the next year, it'll become
  • 32:51available as well.
  • 32:54So, moving on from ESR1,
  • 32:56what about some of the
  • 32:57other, mutations that we look
  • 32:58for?
  • 32:59There are a group of
  • 33:01mutations that are part of
  • 33:02what we call the AKT
  • 33:03pathway.
  • 33:04The AKT pathway is an
  • 33:05alternative,
  • 33:06pathway that, leads to resistance,
  • 33:09sometimes to,
  • 33:11standard anti estrogen therapies.
  • 33:13And there are a number
  • 33:14of genes that are involved
  • 33:15in the pathway, but three
  • 33:16in particular that can be
  • 33:17targeted are the, PIK3CA mutation
  • 33:20or gene, the AKT1 gene
  • 33:22and the P10 gene.
  • 33:24So, when mutations in those
  • 33:25genes are seen,
  • 33:26a medication that can be
  • 33:27useful in combination with, fulvestrant
  • 33:30is called capivacertib
  • 33:32or, TrueCap is the, the
  • 33:33brand name there.
  • 33:36It is,
  • 33:37targeting the similar part of
  • 33:39the, of cell communication as
  • 33:41this older medication,
  • 33:43called pick Ray that many
  • 33:44of you may have heard
  • 33:45of.
  • 33:45Pick Ray is,
  • 33:47is an older oral drug,
  • 33:49that has a lot of
  • 33:50side effects,
  • 33:51and was difficult to use,
  • 33:53I think, for many women
  • 33:54because of the degree of
  • 33:56side effects,
  • 33:57that came along with it.
  • 33:59Cabivastatinib
  • 34:00is approved for all three
  • 34:02of these mutations or for
  • 34:03use in women whose cancer
  • 34:05has all three of these
  • 34:05mutations or any of them.
  • 34:06They don't have all three
  • 34:07at once, just any one
  • 34:08of them.
  • 34:10And it seems to be
  • 34:11useful in women who have
  • 34:12spent,
  • 34:13even less than twelve months
  • 34:15on, their first line endocrine
  • 34:16therapy.
  • 34:18It can cause some side
  • 34:18effects, some GI side effects,
  • 34:20and some rash. It doesn't
  • 34:21cause as much, high blood
  • 34:23sugar as the PICRae, but
  • 34:24it does still require blood
  • 34:26sugar monitoring.
  • 34:29And
  • 34:30sometimes, I mean, really not
  • 34:32it's not rare that a
  • 34:33woman,
  • 34:34when she progresses on first
  • 34:36line therapy might not have
  • 34:37any target mutations.
  • 34:39And so, in that case,
  • 34:41we ask questions like, should
  • 34:42we keep going with our
  • 34:43CDK4six
  • 34:44inhibitor when we change the
  • 34:46underlying anti estrogen medication?
  • 34:48There have been a couple
  • 34:49of different trials, or more
  • 34:51than two, but I'll talk
  • 34:52about two,
  • 34:54that look at this question.
  • 34:56The first of those was
  • 34:57called the PACE trial.
  • 34:59And the PACE trial,
  • 35:01looked at or had two
  • 35:03groups of women in it.
  • 35:04Women who progressed on, their
  • 35:06first line treatment with their
  • 35:07CDK foursix inhibitor. And they
  • 35:09received either full vestrant, the
  • 35:10standard,
  • 35:11approach by itself or full
  • 35:13vestrant with pelbociclib.
  • 35:15Now, most of the women
  • 35:16in that trial had gotten
  • 35:17pelbociclib
  • 35:18as their first CDK4six
  • 35:19inhibitor also. So, this was
  • 35:20really a continuation of the
  • 35:22same,
  • 35:23the same drug for these
  • 35:24women, generally speaking.
  • 35:27And
  • 35:28when using this approach, unfortunately,
  • 35:30there wasn't really any sort
  • 35:32of improvement in how, how
  • 35:33well fobesterone performed.
  • 35:35The cancer progressed,
  • 35:36at the same kind of
  • 35:37pace in both
  • 35:39groups of women.
  • 35:41But what if we switch?
  • 35:42What if we change the
  • 35:43CDK4six inhibitor to one of
  • 35:44the other two?
  • 35:46So the Maintain trial gave
  • 35:47us some information about that
  • 35:49approach.
  • 35:49It compared,
  • 35:51in second line therapy in
  • 35:53women who had gotten the
  • 35:53CDK4six
  • 35:55inhibitor. It compared new endocrine
  • 35:57therapy alone or new anti
  • 35:59estrogen therapy plus ribo cyclob.
  • 36:01And for about eighty eight
  • 36:02percent of patients in that,
  • 36:04study,
  • 36:05that ribo cyclob was a
  • 36:06change. It was different CDK4six
  • 36:08inhibitor than what they previously
  • 36:10received.
  • 36:11In that case, the fulvestrant,
  • 36:13with ribociclib,
  • 36:14did improve,
  • 36:15time on therapy.
  • 36:17So, this doesn't, you know,
  • 36:18kind of tell us about
  • 36:19every situation with, switching CDK4six
  • 36:22inhibitors, but it does give
  • 36:23us some reason to believe
  • 36:24that, that they might be
  • 36:25useful, if there are no
  • 36:26targetable mutations present.
  • 36:30For the for the sake
  • 36:31of time and for the
  • 36:32sake of allowing questions,
  • 36:34I'm, I'm gonna, not really
  • 36:36talk, specifically about medication, you
  • 36:38know, non anti estrogen medications
  • 36:40for, hormone receptor positive breast
  • 36:42cancer. But, but I will
  • 36:43say, also just a little
  • 36:45bit about, trial options that
  • 36:46are available at the, at
  • 36:47the Yale Cancer
  • 36:49Center. The, the trials that
  • 36:50we have tend to turn
  • 36:51over over time. So, specific
  • 36:53trials, you know, kind of
  • 36:55come and go and we
  • 36:56open new ones and we
  • 36:57close.
  • 36:58But,
  • 36:59to think about some of
  • 37:00the common questions,
  • 37:02or the themes in the
  • 37:03questions that,
  • 37:05that are really at top
  • 37:06of mind right now.
  • 37:09So, one, you know, kind
  • 37:10of common theme of the
  • 37:11questions being asked
  • 37:13by the, by trials for
  • 37:14hormone receptor positive breast cancer
  • 37:15is with all of these
  • 37:17new drugs, are there ways
  • 37:18that we can combine them,
  • 37:19into,
  • 37:21you know,
  • 37:22larger combinations
  • 37:23and get better results, for
  • 37:26cancer patients?
  • 37:27So, for instance, we have
  • 37:28a trial right now that
  • 37:29combines cabivacertib
  • 37:31that, AKT pathway inhibitor, the
  • 37:33true cap medication
  • 37:34with a CDK4six
  • 37:36inhibitor
  • 37:36and with fulvestrant. And this
  • 37:38is a trial that's looking
  • 37:39at women who have the
  • 37:40targeted mutations and women who
  • 37:41might not have the targeted
  • 37:43mutations.
  • 37:44Another type of question we're
  • 37:45asking is, are there,
  • 37:47novel ways that we can,
  • 37:49administer these medications that,
  • 37:51that reduces side effects, reduces
  • 37:53toxicity.
  • 37:54So, for instance, we have
  • 37:55a trial, for older women,
  • 37:57women over the age of
  • 37:58sixty five looking at whether
  • 38:00or not we can give
  • 38:01the CDK four six inhibitors,
  • 38:03in the first line setting,
  • 38:05starting at a low dose
  • 38:06and going up rather than
  • 38:07starting at the highest dose
  • 38:08that we offer and going
  • 38:09down if they if if
  • 38:11the dose is too high
  • 38:12for them.
  • 38:13And then, of course, we
  • 38:14we all there's always new
  • 38:16drugs.
  • 38:17And so, we have novel
  • 38:18drug trials, too.
  • 38:20An example is,
  • 38:21this drug, which doesn't even
  • 38:23have a kind of scientific
  • 38:24name yet but still sort
  • 38:25of an industry shorthand.
  • 38:27Relay two thousand six hundred
  • 38:28and eight, which is a
  • 38:30selective
  • 38:31PI3 kinase inhibitor.
  • 38:33And a selective,
  • 38:35adjective sort of refers to
  • 38:36its potential to maybe have
  • 38:38fewer off target effects. And
  • 38:39those off target effects are
  • 38:41what cause toxicity.
  • 38:44Toxicity than than some of
  • 38:46the existing drugs in this
  • 38:47class.
  • 38:49So, I think I'll I'll
  • 38:50stop there,
  • 38:51and,
  • 38:52we could we could open
  • 38:53it up for questions.
  • 38:58And maybe I'll I'll stop
  • 38:59sharing too. You don't have
  • 39:00to look at a black
  • 39:00screen.
  • 39:02Yeah. Dan,
  • 39:03the question that,
  • 39:05on Hartoulo disease and kind
  • 39:07of,
  • 39:08you can see it in
  • 39:10the q and a. It
  • 39:11may come up as answered,
  • 39:13but
  • 39:13I think it's the question
  • 39:15that
  • 39:16is a wonderful one in
  • 39:17terms
  • 39:18of what to do in
  • 39:19the setting of HER2 low
  • 39:21hormone receptor positive breast cancer
  • 39:24and how you're envisioning,
  • 39:26kind of
  • 39:27the sequencing of HER2 ADCs
  • 39:30in this setting,
  • 39:32kind of earlier versus later.
  • 39:34So if you could share
  • 39:35your thoughts on that.
  • 39:36Yeah. Yeah. Absolutely.
  • 39:38You know, this is a
  • 39:39question that actually applies to
  • 39:41both,
  • 39:42the types of breast cancer
  • 39:43that, doctor Shalhoren and I
  • 39:45spoke about. So HER2 low
  • 39:47is sort of a newer
  • 39:48idea,
  • 39:49in in the breast cancer
  • 39:50space or almost like a
  • 39:51new classification
  • 39:55three
  • 39:56buckets that that we've been
  • 39:57talking about is is sort
  • 39:58of how we classically thought
  • 40:00about breast cancer subtypes.
  • 40:01But I I think in
  • 40:02doctor Schallhorn's slide describing what
  • 40:04HER2 HER2 is,
  • 40:06you could see on that
  • 40:07normal,
  • 40:08cell that there was still
  • 40:09HER2 protein. Like, it's when
  • 40:11we talk about HER2 negative
  • 40:13cancers, that doesn't mean there's
  • 40:14no HER2 protein.
  • 40:15So so HER2 low breast
  • 40:17cancers refer to HER2 or
  • 40:19breast cancers that have some
  • 40:20HER2 protein, but not necessarily
  • 40:22this over expressed amount. This,
  • 40:24like, extra HER2 protein that,
  • 40:26that,
  • 40:27has typically made those cancers,
  • 40:29more sensitive to the anti
  • 40:31HER2 drugs.
  • 40:33Why that's an important distinction
  • 40:35to make now, why it's
  • 40:36important to identify cancers that
  • 40:37have some but not too
  • 40:39much HER2 protein
  • 40:40is because one drug in
  • 40:42particular so far and then
  • 40:43surely more in the future.
  • 40:44One one particular drug, the,
  • 40:47trastuzumab, drexatecan,
  • 40:48the HER2 drug that,
  • 40:50that Doctor. Shellhorn talked
  • 40:52about, is actually effective not
  • 40:53only in classically HER2 positive,
  • 40:56breast cancer, but is also
  • 40:58effective
  • 40:58in HER2
  • 41:00low breast cancer.
  • 41:01So, if you're hormone receptor
  • 41:03positive, HER2 negative, but HER2
  • 41:04low, then HER2 can be
  • 41:06it can be very effective.
  • 41:08If you're a triple negative
  • 41:09but HER2 low,
  • 41:10that that, and HER2 can
  • 41:12be very effective.
  • 41:13And so we've been we've
  • 41:14been using that drug for
  • 41:16several years now for those
  • 41:17types of breast cancers as
  • 41:18well.
  • 41:19In in terms of sequencing,
  • 41:22the the
  • 41:23the,
  • 41:26standard, I would say, is
  • 41:28still
  • 41:29for hormone receptor positive breast
  • 41:30cancer is is to really
  • 41:32make the most of the
  • 41:33anti estrogen therapies.
  • 41:35Those cancers are still most
  • 41:36sensitive to anti estrogen approaches,
  • 41:38like the anti estrogen medicines
  • 41:40work best and and longest,
  • 41:41for hormone receptor positive breast
  • 41:43cancers,
  • 41:44early on.
  • 41:46They tend to have fewer
  • 41:47side effects.
  • 41:49Well,
  • 41:51experiences can be mixed, actually.
  • 41:52I don't want to say
  • 41:53that HER2 has
  • 41:54a lot of side effects
  • 41:55for everyone, or that the
  • 41:57antihistamine medications don't have side
  • 41:59effects. It can be significant.
  • 42:01But oftentimes they have fewer
  • 42:03side effects,
  • 42:04than,
  • 42:05the inher tube medication. So,
  • 42:07we still try to use
  • 42:08as many, antiastrogen medications as
  • 42:10possible,
  • 42:12before changing to infusional
  • 42:15chemotherapy based medications. Medications.
  • 42:17And then
  • 42:18there is some, you know,
  • 42:20some recent conversation about whether
  • 42:22HER2 should be the very
  • 42:23first drug that we use
  • 42:24after anti estrogen medication or
  • 42:26if,
  • 42:27if chemotherapies
  • 42:29can,
  • 42:30still, you know, if a
  • 42:32chemotherapy before moving to an
  • 42:33HER2 is appropriate.
  • 42:35And that conversation is really
  • 42:37based on balancing
  • 42:39length of response versus,
  • 42:41versus,
  • 42:42side effects
  • 42:43and whether or not a
  • 42:45drug that might control the
  • 42:46cancer longer but have more
  • 42:47side effects,
  • 42:48whether or not you could
  • 42:49kind of get the same
  • 42:50effect by by turning to
  • 42:52that drug a little bit
  • 42:53later.
  • 42:55So,
  • 42:55it's, it's an exciting space.
  • 42:57I mean and and and
  • 42:58it's a space where I
  • 42:59think there there will be
  • 43:00a lot of new medications
  • 43:01over the over over the
  • 43:02coming years.
  • 43:04And I think for the
  • 43:04listeners, this is your opportunity
  • 43:06when these junctures are occurring
  • 43:08in your care
  • 43:10to be asking your oncologist,
  • 43:12what are my options? What
  • 43:13are my alternatives? And,
  • 43:15I think,
  • 43:16what we all aim for
  • 43:18is to
  • 43:19summarize
  • 43:21currently, as as my colleague
  • 43:22just mentioned, there are so
  • 43:24many options for each line
  • 43:25of therapy in breast cancer.
  • 43:27So a lot will come
  • 43:28down to patients actively deciding
  • 43:31with their oncologist
  • 43:33based on preferences of schedule,
  • 43:35side effects, and so many
  • 43:36other considerations. So don't be
  • 43:38afraid
  • 43:39to be bringing up these
  • 43:41questions.
  • 43:41We we would love to
  • 43:42have these conversations.
  • 43:45There is a there was
  • 43:45a question in the chat
  • 43:47that's also an excellent one
  • 43:48in terms of
  • 43:50when we test,
  • 43:51for these different, targetable pathways.
  • 43:54So doctor Shellhorn will answer
  • 43:55that live. Yeah. No. It
  • 43:57it's a it's a great
  • 43:58question, and doctor O'Neil
  • 44:00talked a lot about targetable
  • 44:02mutations.
  • 44:04It it's applicable for any
  • 44:07type of breast cancer, at
  • 44:08least to some degree. It's
  • 44:09particularly relevant for cancers that
  • 44:11are driven by hormones. So
  • 44:12the hormone receptor positive breast
  • 44:14cancers.
  • 44:16Doctor O'Neil mentioned
  • 44:18specifically
  • 44:18ESR one,
  • 44:21looking at anything in the
  • 44:22AKT pathway. So AKT p
  • 44:24ten PI three kinase,
  • 44:26PIK three CA,
  • 44:27as well as a few
  • 44:28other mutations that have
  • 44:31that are that are considered
  • 44:32druggable. Meaning, we have drugs
  • 44:35that that
  • 44:36focus on those molecular engine
  • 44:39genomic abnormalities
  • 44:40and and help kind of
  • 44:42turn off the switches that
  • 44:44might be driving the cancer.
  • 44:46And so
  • 44:48there's no right answer or
  • 44:50wrong answer to how often
  • 44:52to be testing.
  • 44:54And I think kind of
  • 44:55a a a corollary to
  • 44:57this is how to test
  • 44:59because there are a couple
  • 44:59of ways that you can
  • 45:00test for genomic abnormalities. You
  • 45:02can test the cancer itself
  • 45:04on a biopsy specimen.
  • 45:06So you if you have
  • 45:07a cancer that's got a
  • 45:08deposit in the liver, for
  • 45:09example,
  • 45:10you could get a liver
  • 45:12biopsy to take a sample
  • 45:13of that particular tissue and
  • 45:14then send it to the
  • 45:15to the lab to look
  • 45:16at under the microscope where
  • 45:18we would test for estrogen
  • 45:19receptor, progesterone receptor, HER2, and
  • 45:21we could also then send
  • 45:22it for all of these
  • 45:24molecular tests to look for
  • 45:25any sort of genomic abnormality.
  • 45:30But you can also
  • 45:31do what we call a
  • 45:33liquid biopsy, which is a
  • 45:35blood test,
  • 45:36looking at
  • 45:38DNA from the cancer that
  • 45:40might be circulating in the
  • 45:41blood and getting that same
  • 45:42information in a much less
  • 45:44invasive way. So it doesn't
  • 45:46require a biopsy or a
  • 45:47needle. It just requires a
  • 45:48blood draw.
  • 45:50And so with the advent
  • 45:52of these liquid biopsies,
  • 45:56the the opportunity
  • 45:58is is much less risky
  • 46:01and much easier to do
  • 46:03at any point where it
  • 46:04could theoretically change management.
  • 46:06And so I think most
  • 46:08of us are testing pretty
  • 46:10early on,
  • 46:12maybe not immediately
  • 46:14after a diagnosis of metastatic
  • 46:16breast cancer. But, again, it
  • 46:17might depend on on
  • 46:19what what a patient's,
  • 46:21what a patient's story is,
  • 46:22what their history is, had
  • 46:23they gotten prior treatment, and
  • 46:25if so, how long ago,
  • 46:26and what medicines were they
  • 46:27on?
  • 46:29So you might test as
  • 46:30early as right then and
  • 46:31there at the first
  • 46:32the first sign of metastatic
  • 46:34disease.
  • 46:36But I think for certain,
  • 46:38after progression on first line
  • 46:40therapy for hormone receptor positive
  • 46:42breast cancer because that's when
  • 46:44these molecular targets really become,
  • 46:48become relevant
  • 46:50after progression on on
  • 46:52the first line, usually an
  • 46:54aromatase inhibitor and a CDK
  • 46:55four six inhibitor as doctor
  • 46:57O'Neil described.
  • 47:00But then things can change
  • 47:02over time and things can
  • 47:03develop. So for example, that
  • 47:05ESR one mutation
  • 47:07ESR one mutation
  • 47:09isn't usually very common right
  • 47:11at the time of a
  • 47:12metastatic diagnosis unless someone had
  • 47:14been on,
  • 47:16previous therapies. It but it
  • 47:17can develop,
  • 47:19in even up to forty,
  • 47:20fifty percent of patients who
  • 47:22have been on aromatase inhibitors
  • 47:24over time. So we would
  • 47:26check
  • 47:27periodically
  • 47:28at the time
  • 47:30that there's a a sense
  • 47:31of the cancer starting to
  • 47:32progress,
  • 47:34check for for circulating tumor
  • 47:36DNA, check for mutations
  • 47:38with the idea,
  • 47:40that something targetable
  • 47:41if something targetable were found,
  • 47:43we could then
  • 47:45target it.
  • 47:47And the other time to
  • 47:48consider molecular testing
  • 47:50is
  • 47:51when considering clinical trials because
  • 47:54there are new drugs becoming
  • 47:55available for particular mutations,
  • 47:58certain earlier phase clinical trials
  • 48:01that are,
  • 48:03applicable to patients with certain
  • 48:09FDA approved
  • 48:10targetable,
  • 48:14druggable targets at this point.
  • 48:17So
  • 48:18lots of opportunities, and it's
  • 48:20getting easier and easier to
  • 48:22do.
  • 48:23Kim, I hope that answers
  • 48:24your question.
  • 48:27Yes. And there was also
  • 48:29an additional question about is
  • 48:31ESR one testing ever done
  • 48:32in early stage breast cancer.
  • 48:34And I would say,
  • 48:36one, two points there. These
  • 48:37are
  • 48:38acquired alterations that
  • 48:41occur under selective pressure
  • 48:44of
  • 48:44more longer exposure to anti
  • 48:47estrogen therapy. So you're unlikely
  • 48:49you're gonna have a low
  • 48:50chance of finding it early
  • 48:51on in early stage breast
  • 48:52cancer.
  • 48:53However, there are studies investigating
  • 48:56adjuvant SIRDS in high risk
  • 48:58early stage breast cancer.
  • 49:00So as often happens, if
  • 49:01something is approved and shown
  • 49:03to be effective in metastatic
  • 49:04breast cancer, we do start
  • 49:06testing it in early stage
  • 49:07breast cancer.
  • 49:09There are couple of questions
  • 49:11in the chat that are
  • 49:13are complex, so we might
  • 49:14need to kind of tag
  • 49:15team it.
  • 49:17So,
  • 49:21so let's,
  • 49:23let's take the question from
  • 49:24doctor Ward,
  • 49:27on,
  • 49:28will doctor Ward is one
  • 49:29of our,
  • 49:31amazing breast surgeons,
  • 49:32within Yale network. So,
  • 49:36so in the setting of
  • 49:37oligometastatic
  • 49:38disease
  • 49:38and a primary breast tumor,
  • 49:40who wants to tackle this?
  • 49:41What is the current thinking
  • 49:43on breast surgery?
  • 49:45Doctor Ward wants to be
  • 49:46a little provocative
  • 49:48at our Smilo shares,
  • 49:50Smilo share session.
  • 49:52So the question is specifically
  • 49:54asking if somebody has a
  • 49:56primary breast cancer that's in
  • 49:59the breast and they're diagnosed
  • 50:00with that breast cancer, but
  • 50:01they are found
  • 50:03to
  • 50:04have one or just a
  • 50:06few
  • 50:07spots
  • 50:08on on a staging scan.
  • 50:09So on a CAT scan
  • 50:11or a PET scan, they're
  • 50:12found to have another spot
  • 50:14somewhere else in their body.
  • 50:16Is there a role
  • 50:18for doing surgery
  • 50:20to the breast?
  • 50:22Because at that point, kind
  • 50:23of the traditional way that
  • 50:25we think about this is
  • 50:26that once the cancer has
  • 50:28spread
  • 50:29outside of the breast,
  • 50:31it's no longer considered curable.
  • 50:33And so
  • 50:35curative approaches,
  • 50:36including breast surgery,
  • 50:39are generally
  • 50:40not not considered.
  • 50:42I'd say this is an
  • 50:43area of a lot of
  • 50:45research,
  • 50:46especially
  • 50:48in
  • 50:48HER two positive breast cancer
  • 50:50and in triple negative breast
  • 50:52cancer
  • 50:53because
  • 50:54sometimes
  • 50:55those types of cancers are
  • 50:57very, very responsive
  • 50:58to chemotherapy.
  • 51:02The data that we have
  • 51:04to date
  • 51:05does not show a benefit
  • 51:06to
  • 51:08to,
  • 51:09primary breast surgery
  • 51:11in the setting
  • 51:12of metastatic disease. But these
  • 51:14studies aren't perfect, and so
  • 51:16there are some ongoing
  • 51:17studies being done to look
  • 51:19at particular subsets of patients
  • 51:21to see if there are
  • 51:22benefits. And I,
  • 51:23I will say that for
  • 51:25all of the medical oncologists
  • 51:27in our practice, we all
  • 51:28have patients
  • 51:30who have had,
  • 51:32they may have had metastatic
  • 51:33disease, and they may have
  • 51:35had surgery, and they may
  • 51:36have had radiation,
  • 51:38very strong radiation with the
  • 51:40goal of of trying to,
  • 51:43sterilize
  • 51:44metastatic
  • 51:45deposits.
  • 51:46And they do
  • 51:48really, really well
  • 51:49for a really long time
  • 51:51and don't have evidence of
  • 51:52further cancer. I know I
  • 51:54know that there's at least
  • 51:56one of them on this
  • 51:58call right now who's who's
  • 52:00listening in.
  • 52:02People so we can't fully
  • 52:03explain why that happens, but
  • 52:05what what our goal in
  • 52:06terms of the research going
  • 52:07forward is is to figure
  • 52:08out
  • 52:10who are those patients
  • 52:12that can benefit from a
  • 52:13more,
  • 52:15aggressive approach and continue to
  • 52:17do well in the long
  • 52:18run rather than go through
  • 52:20very big surgeries,
  • 52:22very aggressive treatments, and not
  • 52:24benefit in the long run.
  • 52:28Yeah. I think I think
  • 52:29comes back to
  • 52:31shared decision making and really
  • 52:33looking at each individual patient.
  • 52:35Bringing it back to tumor
  • 52:36board, which is one of
  • 52:37the questions that is densely
  • 52:38packed,
  • 52:40in one of our chat
  • 52:41questions, which which is, does
  • 52:42a single oncologist determine the
  • 52:44treatment plan, or is it
  • 52:45a collective decision?
  • 52:46I can say that,
  • 52:48if it's if something is
  • 52:50very straightforward,
  • 52:51the decision is made between
  • 52:52the oncologist and the patient
  • 52:54in the room right then
  • 52:55and then. But any nuances,
  • 52:57any complexities,
  • 52:58I do wanna assure all
  • 53:00of you that we're talking
  • 53:01all among each other.
  • 53:03We're bringing it back to
  • 53:04tumor board,
  • 53:06and also just encouraging you
  • 53:08that if if you're unsure
  • 53:09or want additional opinions,
  • 53:11it's never wrong to explore
  • 53:13second opinions. It's actually your
  • 53:15right as a patient.
  • 53:18Additional
  • 53:19questions about
  • 53:21just
  • 53:23we kind of answered the
  • 53:24question if it's a new
  • 53:25cancer, are all markers tested
  • 53:27again? And, yes, we we
  • 53:28definitely wanna understand
  • 53:30the biology of a new
  • 53:31recurrence.
  • 53:35And I think maybe, Dan,
  • 53:37take that first part of
  • 53:38the question about late recurrences
  • 53:40and hormone receptor positive breast
  • 53:42cancer
  • 53:42and how it can be
  • 53:43different with different subtypes of
  • 53:45cancer.
  • 53:46Yeah. Yeah. That that is
  • 53:47a that's a great question.
  • 53:49So just like there are
  • 53:51different subtypes of breast cancer,
  • 53:52the the behavior of different
  • 53:54cancers in terms of likelihood
  • 53:55of recurrence,
  • 53:56can be quite different,
  • 53:58and the timing can be
  • 53:59different.
  • 54:00So, the the kind of
  • 54:02rule of thumb is that
  • 54:03the more aggressive,
  • 54:04more,
  • 54:05faster growing
  • 54:07cancers, if they're going to
  • 54:08recur, they're more likely
  • 54:10to recur,
  • 54:12in a shorter timeframe
  • 54:14or at very least the
  • 54:15highest risk periods for recurrence
  • 54:17are earlier on.
  • 54:19So for HER2 positive breast
  • 54:20cancer, triple negative breast cancer,
  • 54:23you sort of have the
  • 54:24highest risk of recurrence over
  • 54:25the first three and then
  • 54:27over the first five years.
  • 54:28And as you get further
  • 54:29from that period of time,
  • 54:31the likelihood of recurrence
  • 54:32gets lower and lower.
  • 54:34HER2 positive breast cancer,
  • 54:37has,
  • 54:39a lower
  • 54:41or hormone receptor positive breast
  • 54:42cancer has a,
  • 54:44a lower likelihood
  • 54:45of coming back
  • 54:47period in most cases when
  • 54:48sort of size and other
  • 54:50things are all considered.
  • 54:52So,
  • 54:53so, for early stage breast
  • 54:54cancer, hormones that are positive
  • 54:56breast cancers are less aggressive,
  • 54:57less likely to come back,
  • 54:59generally speaking.
  • 55:01But that, that because they're
  • 55:03slower growing, sometimes the risk
  • 55:05of recurrence,
  • 55:06over time,
  • 55:07doesn't always drop off to
  • 55:10zero.
  • 55:11You can have
  • 55:12a low risk of recurrence
  • 55:14that can continue out for,
  • 55:15for years sometimes.
  • 55:18I think at, you know,
  • 55:19twenty plus years,
  • 55:20the likelihood of the cancer
  • 55:22coming back is probably quite,
  • 55:24quite low.
  • 55:25You know, just the proof
  • 55:26is in the pudding over
  • 55:27time that it hasn't recurred.
  • 55:31But,
  • 55:32but there are situations, I
  • 55:33think, that we've all seen
  • 55:34where sometimes there can be
  • 55:36late recurrence. And it's important,
  • 55:38I think, for,
  • 55:40for women to just be
  • 55:42mindful of their bodies and
  • 55:44what's going on, with their
  • 55:45bodies and, you know, not
  • 55:47be,
  • 55:49shy about letting
  • 55:52their doctors, be it an
  • 55:53oncologist still or a primary
  • 55:55care doctor, whomever they're
  • 55:57getting their care from,
  • 55:58know if if something feels
  • 56:00unusual.
  • 56:03Is it if that cancer
  • 56:05comes back, is it always
  • 56:06metastatic?
  • 56:07Not necessarily. There are two
  • 56:08types of recurrence. There's local
  • 56:09recurrence and distant recurrence. And
  • 56:09distant recurrence sort of refers
  • 56:09to that that metastatic,
  • 56:12And distant recurrence sort of
  • 56:14refers to that, that metastatic,
  • 56:14disease. The disease that's in
  • 56:16organs outside of the breast
  • 56:17or outside of the nearby
  • 56:18lymph nodes. Local recurrence can
  • 56:20be, the cancer coming back
  • 56:22right in the breast either,
  • 56:23you know, usually in the
  • 56:24vicinity of where it was
  • 56:25originally
  • 56:26or sometimes in the lymph
  • 56:27nodes that,
  • 56:29that are surrounding the breast
  • 56:31that is often the first
  • 56:32kind of place, cancer begins
  • 56:34to to travel to.
  • 56:37So either of those situations
  • 56:39are are possible. I mean,
  • 56:40that's also the reason why,
  • 56:41you know, it's important to
  • 56:42keep getting mammograms.
  • 56:43The the other reason why
  • 56:44it's important to keep getting
  • 56:45mammograms is because
  • 56:48as long as you're,
  • 56:50as long as you're a
  • 56:51woman alive with breast tissue,
  • 56:53there is some risk of
  • 56:54developing a new breast cancer.
  • 56:56And, and and just because
  • 56:58you've had a breast cancer
  • 56:59in the past doesn't mean
  • 56:59that you can never have
  • 57:00a breast cancer again. So
  • 57:02continuing to get mammograms,
  • 57:03so that you pick up
  • 57:05on any new breast cancers
  • 57:06when they're still early is
  • 57:07is important.
  • 57:08New breast cancers can can
  • 57:10certainly show up.
  • 57:12I could I could I
  • 57:13could
  • 57:14talk a little bit about
  • 57:15I think we have a
  • 57:16couple of Yeah. And then
  • 57:17just to clarify for the
  • 57:18audience that, but in the
  • 57:19setting of active metastatic disease,
  • 57:21you're getting thorough scans frequently.
  • 57:24So in that setting, we're
  • 57:26when we do not recommend
  • 57:27additional routine mammography, that has
  • 57:29not been shown to be
  • 57:30helpful.
  • 57:33We're almost at time. Just
  • 57:34one remaining thing is that
  • 57:36in metastatic disease, unlike early
  • 57:38stage breast cancer, the treatments
  • 57:40continue
  • 57:41as long as they're helping
  • 57:42you and as long as
  • 57:43they're controlling the disease process.
  • 57:46But there are situations where
  • 57:47there may be,
  • 57:49you know, we we've had
  • 57:51times where disease has been
  • 57:52completely stable for some time.
  • 57:54So, again, comes back to
  • 57:55shared decision making
  • 57:56about whether,
  • 57:58a certain type of,
  • 58:00de escalation or therapy break
  • 58:02can be considered. But, generally,
  • 58:04things are left open ended
  • 58:05as long as they're helping
  • 58:06you and, keeping the disease
  • 58:09at bay.
  • 58:10Lots of different chemo cycles
  • 58:12and targeted schedules, so we
  • 58:13won't get into that. Definitely
  • 58:15ask your oncology team about
  • 58:17that. But you've all been
  • 58:19such an amazing audience with
  • 58:20really great questions, and I
  • 58:23wanna thank again our speakers
  • 58:25today, doctors,
  • 58:27Shellhorn and doctors O'Neil.
  • 58:29And thank you so much
  • 58:30for joining us. Thank you,
  • 58:32Mary Ellen, for joining.
  • 58:34Thank you. Bye bye.
  • 58:36Bye bye. Okay, man.