Understanding Radiation Treatments for Cancer with Yale's Dr. Peter Glazer

Following are excerpts from a conversation on Yale Cancer Answers on Connecticut Public Radio. The half hour show focused on the role of therapeutic radiation in treating cancers. It included Peter Glazer, MD, PhD and Eric Winer, MD, the director of the Yale Cancer Center and president and physician-in-chief of the Smilow Cancer Hospital in New Haven.

A physician-scientist, Dr. Glazer is a professor of therapeutic radiology as well as genetics in the Yale School of Medicine. He has a lifelong interest in cancer research and patient care as well as the biology of DNA repair pathways. He is Robert E. Hunter Professor of Therapeutic Radiology and Professor of Genetics at the Yale School of Medicine and Chief, Therapeutic Radiology.

Radiation oncology is a medical specialty that uses focused X-rays to kill cancer cells. It involves techniques like brachytherapy, where radioactive sources are placed near a tumor, and the use of linear accelerators (LINACs) to treat deep-seated tumors with high-energy X-rays.

Radiation causes ionization of molecules within cancer cells, leading to DNA damage. This damage prevents cells from repairing themselves, leading to cell death and tumor regression.

About 60% of all cancer patients with many different tumors are treated with radiation. It’s used for head and neck cancers, breast cancer, prostate cancer, brain tumors, and gastrointestinal and gynecologic cancers. It can be an alternative to surgery or used in conjunction with it, especially for localized diseases.

Early treatments used simple X-ray imaging to identify tumors and their locations and there was limited ability to tightly control the focus of the radiation beam. Advances now include three-dimensional imaging (CT, MRI, PET) and complex beam arrangements, allowing more precise targeting of radiation on tumors. That spares more healthy tissue around the tumors and reduces side effects from the radiation treatment. Image-guided therapy involves using onboard imaging devices to adjust treatment in real time, improving precision.

One myth is that radiation causes severe skin burns, which was more common with older techniques. Modern methods have significantly reduced skin and other side effects. Also, concerns about radiation causing cancer are addressed through focused delivery and are generally low risk, especially in adults.

These are advanced techniques for treating brain metastases with high precision, focusing on individual lesions and sparing healthy brain tissue. This approach has improved patient outcomes and quality of life.

New technologies incorporate PET imaging to track tumor position and movement, enhancing treatment accuracy.

Yes, radiation can be combined with immunotherapy to enhance immune response and with DNA repair inhibitors to increase cancer cell sensitivity to radiation.

The field is moving towards more precise and individualized treatments using advanced imaging and AI, along with developing targeted biological agents that make tumors more sensitive to radiation without affecting healthy tissue.

While advancements may change treatment balances, both radiation and surgery have their roles, and technological improvements in both fields will continue to enhance patient care.

To learn more about Therapeutic Radiology visit Yale Medicine here.