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Endoscopic Experts Team Up to Expand Yale Program to Treat Achalasia and Early Cancers

August 12, 2022
by Jane E. Dee

Anil Nagar, MD, and Harry Aslanian, MD, veteran members of Yale’s advanced endoscopy program, have teamed up to expand the use of complex endoscopic procedures to treat achalasia and other swallowing disorders as well as early cancers of the gastrointestinal tract.

Nagar, associate professor of medicine (digestive diseases), and Aslanian, professor of medicine (digestive diseases), at Yale School of Medicine (YSM), bring a multidisciplinary approach to the treatment and diagnosis of disorders of the esophagus and early intestinal cancers at Yale New Haven Hospital and Yale Cancer Center.

These procedures are performed in only a few centers in the country. They include POEM (Per-Oral Endoscopic Myotomy), which accesses the sphincter muscle at the bottom of the esophagus using an endoscopic device that is passed through the mouth, and ESD (endoscopic submucosal dissection), which can treat early intestinal cancers.

Nagar and Aslanian work closely with their colleagues in oncology, the Gastrointestinal Motility Program, and gastrointestinal (GI) surgery to provide a multidisciplinary and patient-centered approach using advanced endoscopy tools.


Nagar and Aslanian first met 21 years ago when Nagar was a junior attending faculty member and Aslanian was a senior fellow. Since then, Nagar has been the endoscopy director at the West Haven Veterans Hospital while Aslanian has helped to lead the endoscopy program in the Section of Digestive Diseases in the Department of Internal Medicine at YSM.

“I've returned to partner with Dr. Aslanian to expand these services by collaborating with our colleagues across YSM,” Nagar said.

Nagar and Aslanian both spent time in Japan, where these complex procedures were developed, and have incorporated the techniques into their advanced endoscopy practice.

“Dr. Nagar is an incredibly skilled and thoughtful endoscopist and gastroenterologist, and we are very excited to work together to provide advanced endoscopic approaches to problems that previously could only be treated surgically,” Aslanian said.

In addition to Aslanian and Nagar, the advanced endoscopy team members are Priya Jamidar, MBChB, professor of medicine (digestive diseases), and endoscopy director; Thiruvengadam Muniraj, MD, associate professor of medicine (digestive diseases) and associate chief for endoscopy for Digestive Health for the Yale New Haven Health System; James Farrell, MBChB, professor of medicine and director of the Yale Center for Pancreatic Diseases; and Hillary Drumm, APRN.

New Advanced Treatments

Initially, endoscopy was used to treat benign lesions, but advanced endoscopy procedures now can be used to remove very early cancers. Aslanian and Nagar specialize in a procedure targeting GI tumors and GI cancers called endoscopic submucosal dissection, or ESD. The complex technique is performed using special endoscopic devices to dissect superficial gastrointestinal tumors as a single piece. These are usually large non-cancerous tumors of more than 3 centimeters in size, Nagar said. The standard practice has been to remove the tumor by cutting it into pieces. The advanced endoscopy ESD approach is to remove the tumor in one piece to preserves the tumor’s architecture. “Since we are able to take a tumor out as a single piece, we can frequently treat very early cancers,” Nagar explained.

In addition to performing ESD procedures, Nagar and Aslanian also treat and diagnose Barrett's esophagus, an abnormality of the esophagus that is generally related to reflux. Nagar and Aslanian use the ESD technique, along with EMR (endoscopic mucosal resection) to take out large dysplastic lesions and treat intramucosal cancer.

Newer technology such as optical endoscopic tools with high-definition light and narrow band imaging allows them to look at a tumor’s blood vessels, its architecture, and overall appearance. “We can, quite accurately, predict malignant versus benign and even the depth of invasion, and adjust treatment plans as necessary,” Nagar said.

POEM Procedures

Extending the technique of ESD to dissect a tunnel in the submucosal space allows Nagar and Aslanian to treat diseases associated with deeper layers of the intestine including the muscular layer. The disease that is the paradigm for these procedures is achalasia, a rare disorder that causes difficulty swallowing.

Traditionally, the treatment of this disorder was a surgical cutting of the muscle, or an endoscopic balloon dilation. But over the last 10 years, treatment has evolved where the endoscopy team passes the endoscope through the mouth and tunnels into the esophagus to reach and perform a myotomy of the tight sphincter muscle at the bottom of the esophagus, without requiring an incision from outside the body.

Aslanian and Nagar also use this technique to treat disorders of delayed gastric emptying (refractory gastroparesis) and swallowing difficulties of the upper esophagus. The procedure to treat esophageal disorders is called E-POEM, or Esophagus Peroral Endoscopic Myotomy. When the procedure is done in the stomach, it's called a G-POEM, or gastric POEM for gastroparesis. Z-POEM, or Zenker’s POEM is used to treat Zenker's diverticulum, which is a cause of difficulty swallowing in the upper esophagus.

Yale Digestive Diseases faculty includes a team of gastroenterologists and hepatologists whose expertise focuses on diseases of the gastrointestinal tract and liver. Faculty members specialize in disorders of the esophagus, stomach, liver, gallbladder, pancreas, small intestine, colon, and rectum. Evaluations, diagnostic and therapeutic outpatient endoscopy services serve referrals from the region. To learn more about their work, visit Digestive Diseases.

Submitted by Jane E. Dee on August 12, 2022