Endoscopic Submucosal Dissection

Curing Early GI Cancers Without Surgery

Maybe it’s the sushi, or maybe it’s the Korean barbecue, but for some reason stomach cancer is more prevalent in Asia than in the United States. That’s why 10 years ago doctors in Japan developed a minimally invasive technique called endoscopic submucosal dissection to overcome the technical limitations of removing early gastric (stomach) cancer with other endoscopic tools.

About two years ago Shai Friedland, MD (associate professor, Gastroenterology and Hepatology), began performing the procedure at Stanford. That was after Friedland met several Japanese and Korean pioneers of the technique, observed them perform the procedure in Korea, attended courses they had taught in the United States, and practiced the technique under their careful supervision.

To date, Friedland has performed about 50 cases, and he’s currently collaborating with Dong-Hoon Yang, MD, a clinical associate professor at Asan Medical Center in Seoul, Korea, on a manuscript about a simplified endoscopic submucosal dissection technique in the colon. The two doctors are comparing the success of the technique at the two institutions, and they expect the paper to show that the technique is successful in both countries.

Because relatively few patients in the US have the stomach lesions that would merit the procedure, only a couple of doctors in this country have had an opportunity to perform endoscopic submucosal dissection, a procedure that usually takes one to two hours.

“The procedure is very challenging technically to perform, and it is relatively risky, especially for a doctor who is not very experienced in the technique,” says Friedland.

However, the procedure has many advantages over standard treatment methods.

“The endoscopic technique that this replaces is known as EMR – endoscopic mucosal resection,” Friedland points out. “That’s a technique where you also inject fluid underneath the lesion, but you use a snare, which is like a lasso with an electric cautery, to remove one piece at a time until the whole lesion is removed. That technique is suitable for very small lesions or when you don’t care about removing the lesion all in one piece. We use that technique with a lot of colon polyps because they’re more benign than these stomach cancers, and it seems to work pretty well in those instances. But for earlier stomach cancer, EMR is really inferior to endoscopic submucosal dissection. In those cases it’s important to remove the lesion in one piece, and those lesions are often fairly large—much larger than a snare can get.”

Often when there are larger lesions in the stomach, the recommended treatment is a total gastrectomy, which is open surgery to remove the entire stomach and connect the esophagus directly to the intestine.

“While a total gastrectomy is not overly complex and takes only a few hours, it is generally very difficult for patients to live well and eat well after that kind of surgery. They’ve lost their entire stomach, which means they then can no longer eat large meals, they can’t enjoy their food as much as they did before, and they lose a lot of weight,” Friedland says.

Before development of endoscopic submucosal dissection it was only possible to remove relatively small lesions in one piece, which the Japanese found to be sub-optimal for early gastric cancers, according to the Stanford professor.

“Because we’re just removing the mucosa—the inner lining of the stomach—the wound heals on its own in a few weeks, and the patient is basically left with a stomach that works as well as it did before. So that’s really the great advantage of these minimally invasive treatments,” Friedland says.

Endoscopic submucosal dissection is ideally suited for selected patients with pre-cancerous conditions or early cancer in their stomach, esophagus, colon, or rectum.