The Epidemiology Of Esophageal Cancer Has Changed Dramatically During The past Decade. The Incidence Of Adenocarcinoma Associated With Barrett's metaplasia Is Rising Dramatically Faster Than Any Other Tumor In North America. squamous Cell Cancer Of The Esophagus Continues To Afflict Nearly 10,000 americans Annually.1
Despite its recent increases, esophageal cancer accounts for approximately 1.5 percent of all cancers in men, and 0.5 percent of all cancers in women.2 Estimated new esophageal cancer cases in the United States during 2001 amounted to 9,900 men and 3,300 women. It claimed the lives of an estimated 9,500 men and 3,000 women.3 Etiologic factors for esophageal cancer include smoking and alcohol use, but the association is much stronger for squamous cell carcinoma.2 There is little or no association of reflux with squamous cell carcinoma, though it is strongly linked to adenocarcinoma.
Thirty years ago, the most common esophageal cancer was squamous cell carcinoma in the middle third of the esophagus that developed in male patients with a significant smoking and/or alcohol history. Today, the cause of esophageal cancer has changed, such that the most common esophageal cancer in 2001 is an adenocarcinoma that arises in the lower third of the esophagus or at the junction of the stomach and esophagus. Most of these patients are male, and have little or only moderate history of alcohol or tobacco use. Quite often they will have a history of gastric reflux. Reflux, especially alkaline reflux, is believed to contribute to the rise in esophageal cancer.2
Esophageal cancer responds poorly to treatment because it spreads early, and the morbidity with surgical and medical treatment is high. The prognosis, as revealed in national reports, is poor; the majority of patients die within 12 months and only 10 percent to 20 percent are alive at five years. These poor results have prompted the use of combination therapeutic modalities to improve outcome.
The exact causes of esophageal cancer are not known, but studies show that any of the following factors can increase the risk of developing it:4
Age: Most people who develop esophageal cancer are age 60 or older.
Sex: Cancer of the esophagus is more common in men.
Tobacco Use: Smoking cigarettes or using smokeless tobacco is one of the major risk factors for esophageal cancer.
Alcohol Use: Chronic and/or heavy use of alcohol is another major risk factor for esophageal cancer. People who use both alcohol and tobacco have an especially high risk of esophageal cancer.
Barrett's Esophagus: Long-term irritation can increase the risk of esophageal cancer. Tissues at the bottom of the esophagus can become irritated if stomach acid frequently "backs up" into the esophagus -- a problem called gastric reflux. During time, cells in the irritated part of the esophagus may change and begin to resemble the cells that line the stomach. Known as Barrett's esophagus, this condition is a premalignant condition that may develop into adenocarcinoma of the esophagus.
Other Types of Irritation: Other causes of significant irritation or damage to the lining of the esophagus, such as swallowing lye or other caustic substances, can increase the risk of developing esophageal cancer.
Medical History: Patients who have had other head and neck cancers have an increased chance of developing a second cancer in the head and neck area, including esophageal cancer.
Barrett's esophagus develops in some people who have chronic gastroesophageal reflux disease (GERD) or inflammation of the esophagus (esophagitis).5 In Barrett's esophagus, the normal squamous cells that line the esophagus turn into specialized columnar cells not usually found in humans. Once the cells in the lining of the esophagus have turned into columnar cells, they will not revert back to normal. Five percent to 10 percent of people with Barrett's develop cancer of the esophagus. Because of the cancer risk, patients are screened for esophageal cancer regularly.
Treatment for esophageal cancer depends on the size, location and extent of the tumor and the general health of the patient.4 A combination of treatments may be used to control cancer and/or improve the patient's quality of life by reducing symptoms.
Surgery is the most common treatment for esophageal cancer. Usually, the surgeon removes the tumor along with all or a portion of the esophagus, nearby lymph nodes and other tissue in the area. The surgeon connects the remaining healthy part of the esophagus to the stomach so the patient is still able to swallow. Radiation therapy or radiotherapy uses high-energy rays to kill cancer cells. It may be used alone or with chemotherapy as primary treatment if the size or location of the tumor would make an operation difficult. Laser therapy uses high-intensity light to destroy tumor cells. The relief of a blockage can help to reduce symptoms, especially swallowing problems. Photodynamic therapy (PDT), a type of laser therapy, uses drugs that are absorbed by cancer cells. When exposed to a special light, the drugs become active and destroy the cancer cells.
Richard Kozarek, MD, chief of gastroneurology for the Gastrointestinal Center of Virginia Mason Medical Center and clinical professor of medicine at the University of Washington, Seattle, recognizes stents as a mechanism of palliating people with an obstructing fistula or neoplasm. While stents for esophageal cancer tend to be inserted at the end-of-life stage, patients still want to be able to eat and swallow.
"Laser used to be commonly used," he says. "Irradiation tends to decrease the bulk of a tumor, but it may take weeks to get an effect. Some will use stents before irradiation. As a palliative maneuver, the stent goes in small, expands to its predetermined diameter and allows people to eat. It literally pushes the tumor out of the way."
Because stents generate a lot of force against the tumor, Kozarek points out that patients can experience pain while it is expanding.
Most esophageal stents evolved from a rigid tube with a stainless steel coil to a self-expandable metal stent (SEMS). "The advantages of the latter are that you don't have to use a big introducer to put them into place and you don't have to dilate to such a degree that there is a risk with perforation," says Kozarek.
Says Dr. John Vargo, therapeutic endoscopist, Cleveland Clinic Foundation, "Expandable metallic stents are probably one of the biggest advances in the past few years for the treatment of malignant dysphasia. Plastic stents were unwieldy in their size, almost always required general anesthesia for placement and required aggressive dilation almost to the point of perforation. Many times patients did perforate, so plastic stents were associated with morbidity and mortality."
Vargo cites randomized controlled trials of metallic vs. plastic stents. "Metallic stents are superior in ease of placement and less costly because we are not using general anesthesia to place them," he says. "Most of my cases are placed in an ambulatory environment. Patients go home the same day. We use fluoroscopy or X-ray to help find the exact dimensions of the tumor and occasionally we have to dilate the tumor and place the stent across the area of narrowing."
The bottom line with esophageal stents is that they palliate malignant dysphasia.
For a complete list of references log on to www.endonurse.com.
LEFT TO RIGHT: A view of an obstructing adenocarcinoma; A retroflexed view of the cancer extending into cardia; A view of a successfully deployed stent.
The following Web sites offer more information about esophageal cancer: