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The most common types of esophageal cancer are squamous cell carcinoma and adenocarcinoma, which develop in the cells that line the wall of the esophagus. These cancers may develop anywhere in the esophagus and may appear as a narrowing (stricture) of the esophagus, a lump, an abnormal flat area (plaque), or an abnormal connection (fistula) between the esophagus and the airways that supply the lungs. Less common types of esophageal cancer include leiomyosarcomas (cancers of the smooth muscle of the esophagus) and metastatic cancer (cancer that has spread from elsewhere in the body).
Cancer of the esophagus affects about 15,500 people each year in the United States. Both squamous cell carcinoma and adenocarcinoma are more common among men than women. Squamous cell carcinoma is more common among blacks, whereas adenocarcinoma is more common among whites. The frequency of adenocarcinoma has been increasing rapidly in the United States since the 1970s, especially among white men and is now more common than squamous cell carcinoma in the lower part of the esophagus.
Risk Factors
Tobacco use (any kind) and alcohol are the most important risk factors for developing esophageal cancer, although more so for squamous cell carcinoma than for adenocarcinoma. People who have had certain human papillomavirus infections, who have had head and neck cancer, or who have undergone radiation therapy to the esophagus for treatment of other nearby cancers are at greater risk of developing esophageal cancer.
People with an existing disorder of the esophagus, such as achalasia, esophageal webs (Plummer-Vinson syndrome), or narrowing due to having once swallowed a corrosive substance (such as lye), are also at greater risk of developing esophageal cancer. Prolonged irritation of the esophagus from the repeated backflow of stomach acid (gastroesophageal reflux) can cause a precancerous condition called Barrett's esophagus. Although esophageal cancer from Barrett's esophagus remains relatively rare in most industrialized countries, its frequency is increasing faster than all other esophageal cancers.
Symptoms
Early-stage esophageal cancer may go unnoticed. The first symptom is usually difficulty in swallowing solid foods, which develops as the growing cancer narrows the esophagus. Several weeks later, swallowing soft foods and then liquids and saliva becomes difficult. Weight loss is common, even when the person continues to eat well. People may have chest pain, which feels like it travels to the back.
As the cancer progresses, it commonly invades various nerves and other tissues and organs. The tumor may compress the nerve that controls the vocal cords, which can lead to hoarseness. Compression of surrounding nerves may cause Horner's syndrome (see Autonomic Nervous System Disorders: Horner's Syndrome), spinal pain, and hiccups. The cancer usually spreads to the lungs, where it may cause shortness of breath, and to the liver, where it may cause fever and abdominal swelling. Spread to bones may cause pain. Spread to the brain may cause headache, confusion, and seizures. Spread to the intestines may cause vomiting, blood in the stool, and iron deficiency anemia. Spread to the kidneys often causes no symptoms.
In late stages, the cancer may completely block the esophagus. Swallowing becomes impossible so that secretions build up in the mouth, which can be very distressing.
Diagnosis
Endoscopy, in which a flexible viewing tube (endoscope) is passed through the mouth to view the esophagus, is the best diagnostic procedure if esophageal cancer is suspected. Endoscopy also allows the doctor to remove a tissue sample (biopsy) and loose cells (brush cytology) for examination under a microscope. An x-ray procedure called a barium swallow (in which the person swallows a solution of barium, which shows up on x-rays) can also show the obstruction. Computed tomography (CT) and ultrasonography scans performed through an endoscope inserted in the esophagus may be used to further assess the extent of the cancer.
Prognosis and
Treatment
Because esophageal cancer usually is not diagnosed until the disease has spread, the death rate is high. Fewer than 5% of people survive more than 5 years. Many die within a year of noticing the first symptoms. Because nearly all cases of esophageal cancer are fatal, the doctor's main objective is to control symptoms, especially pain and the inability to swallow, which can be very frightening to the person and loved ones (see Death and Dying: Difficulty Swallowing).
Surgery to remove a tumor offers the most prolonged relief but seldom cures, because the cancer usually has spread by the time of surgery. Chemotherapy, alone or with radiation therapy, may relieve symptoms and lengthen survival time by a few months. Sometimes pre-operative radiation therapy combined with chemotherapy can increase the surgical cure rate. Other measures that aim only to relieve symptoms include widening (dilating) the narrowed area of the esophagus and then inserting a tube (a stent) to keep the esophagus open; bypassing the tumor using a loop of intestine; and performing laser phototherapy, in which a high-energy beam of light is directed at the growth to destroy the cancer tissue obstructing the esophagus.
Another technique for symptom relief is photodynamic therapy, in which a light-sensitive dye (contrast agent) is given intravenously 48 hours before treatment. The dye is absorbed by cancer cells to a much greater degree than by the cells of normal surrounding esophageal tissue. When activated by light from a laser passed into the esophagus through an endoscope, the dye destroys cancer tissue, thus opening the esophagus. Photodynamic therapy destroys obstructing lesions more rapidly than radiation or chemotherapy in people who cannot tolerate surgery because of poor health.
Adequate nutrition makes any type of treatment more feasible and tolerable. People who can swallow may receive concentrated liquid nutritional supplements. People who cannot swallow may need temporary tube feeding or intravenous feeding.
Because death is likely, a person with esophageal cancer should make all necessary plans. The person should have frank discussions with the doctor about wishes for medical care (advance directives—see Legal and Ethical Issues: Advance Directives) and the need for end-of-life care.
Last full review/revision December 2007 by Elliot M. Livstone, MD
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