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Esophageal Cancer

There are 10,000 cases of esophageal cancer per year in this country, and, unfortunately, most of those are un-resectable at time of presentation esophagus cancer, esophageal cancer, cancer of the esophagus. 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.

In the modern era it is important to at least consider now radiation therapy. There are special protocols designed to shrink tumors rapidly over a short period of time, such as over ten fractions, but importantly, the response rate is quite variable especially for the responses for adenocarcinomas. The time to see tumors shrink is also quite variable. It can take as long as six weeks.

Since the advent of the fiberoptic endoscope, a number of interventional technologies have evolved, and listed here in the order in which they appeared. Dilation therapy, simply using a bougie or a balloon dilator is simple, quite easy to perform, but as you would imagine, the benefit is quite short-lived and typically, repeated dilatations are necessary. Aggressive dilatation can result in a dilatation in up to a quarter of the patients. Injection therapy is also quite simple, technically. You basically inject absolute alcohol or some other solutions into a kind of fleshy, soft, exophytic tumor where it works the best.

What about rigid prostheses? Those of you who have passed a couple of the Celestin type or other rigid type tubes probably get a visceral response just looking at this slide. Itís a fairly uncomfortable procedure both for the endoscopist as well as the patient, but basically this is where a rigid plastic tube is shoved through the distal tumor with the use of a pusher-tube device. Whatís the problem with this technique? Well, technically itís difficult to perform.

The outside lumen is about 18, the outside of the diameter of the tube is typically 16-18 mm in size, so it requires fairly aggressive either single or serial dilatation maneuvers in order to allow the tube to be eventually advanced. Frequently general anesthesia is necessary for the patient to tolerate this procedure. Again, when you are pushing fairly vigorously with this device.

Laser photoablation is ideal for an exophytic, non-circumferential type of tumor. Again that fleshy type of tumor. And with a couple of laser sessions you can see that the tumor melts away, and with further efforts you can see the laser being fired. This is again with the YAG laser. You can create a pretty significant lumen. What are the downsides?

The new kids on the block are the self expanding metal stents. Brent showed us a picture earlier of their use in the biliary tract. They were first modified for esophageal use about 1991. This is an example of the Schneider Wallstent in place. The advantage of this type of device - obviously those of you who place it are quite aware of this - but it can be mounted onto a delivery catheter where itís held in check with a sheath. When the sheath is withdrawn the stent is deployed, and then it provides a force against this esophageal tumor, hopefully providing a nice lumen such as seen here where the lumen is about 18 mm.

Finally, the last self-expanding stent is the Wilson-Cook Z stent. This is a stainless steel product with interlocking mesh triangles, again with a polyurethane coating to prevent tumor ingrowth. It comes in different sizes. One of the nice features of this stent is when it is deployed there is very minimal retraction. That is, when the stent pops in it doesnít shrink down very much.

This table is in your syllabus but it kind of outlines some of the specs of the different stents. But keep in mind, the size of the delivery system is very important. If you have a large delivery system that is going to require a number of dilation maneuvers perhaps to place that, whereas if you have a very small delivery system, 18 French or 24 French, itís quite easy to pop this in without even a single dilation maneuver. Four of the five stents are now covered, and thatís important for preventing tumor ingrowth and also for sealing tracheoesophageal fistulas. The radial force is quite different. If youíve ever felt the EsophaCoil.

Iím going to show a little video tape again. The placement of a couple of stents. For those of you who havenít been doing this much, just to show Ö first, the EsophaCoil. This is typical adenocarcinoma of the distal esophagus. Itís important to note where the tumor is so you have to mark the tumor margins both externally and internally. This is injecting radiocontrast, either lipid or water soluble. Thereís already a mark distally. I think you can just see it, and now injection proximally into the margin of the tumor so you can gauge your stent placement. You have to size your stents.

We try to get at least 2-3 cm of stent beyond the proximal and distal margins in order to allow for the shrinkage which may occur. Once the stent is passed through the stricture area, the EsophaCoil has kind of a tricky delivery system. You have to release three different tabs. The first tab is the distal release, which releases the Ö kind of a string release device which allows the distal part to be released. And you turn the device and release the proximal portion of the stent. Again, you notice the shrinkage which occurs, a fairly significant amount. 

How accepted are the stents right now? Well things really changed in 1993. This was the first randomized controlled trial comparing the plastic rigid-type stents to the Ö this was actually the Wallstent that was used, a randomized trial and following this the stents really gained a lot of acceptance and began to be used much more frequently. This study, as you will recall, isnít a perfect study in that patients were kept in the hospital for a long time for the plastic stents, for dilation and general anesthesia and such, but the important take-home message is that the expandable metal stents were just as effective technically and functionally.