Colon Cancer 2
What about the second indication, for effective palliation? Again, very limited numbers here so take this certainly with a grain of salt, but effective palliation can be achieved with an expandable stent. The duration of therapy when stents were positioned averaged about 17 weeks. One patient went as long as 64 weeks. What are the problems? Certainly migration in the colon with colonic motility and especially when the stent is placed at an anatomical curve, the splenic flexure for example, those stents are much more likely to migrate. So the numbers are still quite high. From Dr. Baron’s study of 25 patients, again the concern is migration in about 20%. Perforation occurred in four patients and that was primarily, they thought, due to the balloon dilation performed before the stent was placed. One interesting point, when they placed the stent, provided contrast material to check its site and to rule out perforation, and found an unrecognizable site of proximal obstruction in a couple of patients. So obviously that’s a limitation of this process.
This is very flexible. The endoprothesis device, it’s very flexible and the nice thing about that is it can be mounted on a very very small delivery system. Again, this has now been recently approved by the FDA. This is the delivery system with the typical stent mounted approach where the sheath is then withdrawn and the stent is then released. You can see the radiopaque markers which aid in fluoroscopic placement and guidance. Again, the retraction is a problem. There is a fairly significant amount of retraction which occurs with these devices so you kind of have to measure that as best you can. The main advantage is, as shown, it can be passed through the biopsy channel of the colonoscope and here we will see the stent being placed across the stricture here, the stent is being deployed. You can see the kind of shrinking down again. This is where the stricture is and now you can see contrast material, I hope you can see that, passing through the stent itself.
There are 10,000 cases per year in this country of esophageal cancer, and unfortunately most of those are un-resectable at time of presentation. The five-year survival was quite poor, and the life expectancy averages about six months in patients with un-resectable disease. Now as endoscopists, and physicians, our goal is to relive the most bothersome symptom for the patient, that is, the one that affects their quality of life most significantly, and that is dysphagia, and at the time providing nutritional access and also a means to prevent aspiration.