What is esophageal cancer?
How common is esophageal cancer?
What causes esophageal cancer?
Who gets esophageal cancer?
What are the symptoms of esophageal cancer?
How do I know if I have esophageal cancer?
What evaluation is appropriate to diagnose esophageal cancer?
How is staging of esophageal cancer performed?
How is esophageal cancer treated?
What is the prognosis for esophageal cancer?
The esophagus is a muscular tube that extends from the neck to the abdomen and connects the mouth to the stomach. Cancer, or a malignant tumor, is the result of uncontrolled growth of cells located in a particular region of the body. Cancers can be made of many different types of cells. The lining of the esophagus is the most common region for cancers of the esophagus to begin. Most of the length of the esophageal is lined with squamous cells, which, if they degenerate into a malignant tumor, give rise to a type of cancer called squamous cell cancer. The very bottom portion of the esophagus and the region where the esophagus and stomach join are lined with columnar cells that can give rise to malignant tumors called adenocarcinomas. Other rare forms of esophageal cancer include sarcoma and small cell cancer.
Esophageal cancer is not nearly as common as cancers of the breast, lung, prostate, or colon. In the U.S. we expect an annual incidence of esophageal cancer of between 12,000 and 18,000 new cases. It's difficult to state a more exact number because there is some controversy about whether cancers of the small region where the esophagus and stomach join should be considered esophageal cancer or stomach cancer. Interestingly, it's this region which gives rise to cancers that are increasing in frequency faster than any other type of cancer in the U.S.
The esophagus is a muscular tube that extends from the neck to the abdomen and connects the mouth to the stomach. (Click on the illustration to enlarge it.)
The causes for esophageal cancer in the U.S. differ depending in what type of cancer is being considered. The risk factors for squamous cell cancer include smoking tobacco and heavy use of alcohol. People who are infected with human papilloma virus are also at increased risk. Those who suffer from achalasia (a benign esophageal disease), chronic scarring of the esophagus due to prior injury, or tylosis (a rare genetic disorder) are also at increased risk.
Typical places for different types of cancer
The risk factors for adenocarcinoma are less well understood. People who have Barrett's esophagus, an abnormal lining of the bottom part of the esophagus that is related to acid reflux problems, are at increased risk, as are people who have longstanding acid reflux problems alone.
Most people who develop esophageal cancer are in their 50's to 70's. In the U.S. squamous cell cancers develop more often in men than they do in women, and are more common among African-Americans than among Caucasians. This is likely due to the higher incidence of specific risk factors in this population than to any increased risk based on race. Adenocarcinomas are more common among men than women and are much more likely to occur in Caucasions than in minorities.
The most common symptom of esophageal cancer is difficulty swallowing, or the sticking of food before it gets into the stomach. This is usually a progressive problem which begins initially when large pieces of poorly chewed food are swallowed, but can worsen to the point that thin liquids won't go down easily. Esophageal cancer may also cause weight loss, pain with swallowing, regurgitation of undigested food, and bleeding manifested by vomiting blood or passing old blood with bowel movements.
The main symptoms of esophageal cancer, including difficulty swallowing and weight loss, should prompt a visit to your physician. There is no simple way to determine whether you have esophageal cancer. Tests are usually necessary to determine whether there is a growth (or tumor) in the esophagus that is creating problems with swallowing. If such a problem is identified, a biopsy is necessary to confirm the diagnosis.
In someone who is suspected of having esophageal cancer, several tests are appropriate. An endoscopy is usually the first step in evaluation. This is an outpatient test performed under sedation in which a flexible telescope is passed through your mouth and down your esophagus into your stomach. The telescope permits the physician performing the test to look at the lining of the esophagus and take a small bite of tissue, or biopsy, of any areas that look suspicious. The tissue is looked at under a microscope to determine whether there is cancer present.
Other common tests include an x-ray of the esophagus and stomach performed while swallowing a liquid that shows up on x-rays, giving your physician a picture of the lining of your esophagus. Most patients will also undergo computed tomography, or a CT scan, of the chest and abdomen to get a picture of the lungs, liver, and other organs surrounding the esophagus.
If an esophageal cancer is diagnosed, staging is the process that physicians use to determine how advanced the cancer is and whether the cancer has spread. Depending on the type of cancer, specific staging tests are performed aimed at investigating the most common areas for that cancer to spread. For esophageal cancer, the common areas of spread are the lymph glands (or lymph nodes), lungs, liver, adrenal glands, kidneys, bones, and lining of the chest and abdomen.
The CT scan of the chest and abdomen is useful to evaluate the lungs, liver, and adrenal glands for spread from an esophageal cancer, but is not much good for looking at lymph nodes for potential cancer spread. The main tumor and adjacent lymph nodes are sometimes evaluated using endoscopic ultrasonography, or EUS. This is an endoscopic test that utilizes a special telescope which emits ultrasound waves that can produce a picture of the tumor and surrounding lymph nodes. A bone scan is sometimes performed to determine whether the cancer has spread to the bones. Another useful staging test is PET scanning, which measures the level of metabolic activity in tissues and thus provides unique information about possible cancer locations.
The treatment of any cancer depends in part on the stage of cancer at the time it is diagnosed. Other considerations include the overall condition of the patient and specific symptoms the patient is having. Most cancers of the esophagus are diagnosed at a relatively late stage because symptoms of swallowing difficulty don't begin until many months after the cancer begins to grow.
For patients in whom the cancer has not spread to other organs, and thus is potentially curable, surgery to remove the majority of the esophagus is the main form of therapy. Many patients also receive chemotherapy (intravenous drug therapy) and radiotherapy (x-ray treatments) after surgery although there is little information to prove that these additional treatments are useful. Many cancers centers are investigating the usefulness of giving chemotherapy or chemotherapy combined with radiotherapy prior to surgery for patients who are potentially curable.
For patients who are found to have cancer spread to other organs or who, for some other reason, can't have surgery, combined chemotherapy and radiotherapy is the most common treatment. Since swallowing difficulties are not always immediately relieved by this combined therapy, other means to improve swallowing are available. These include stretching the esophagus, burning or melting the tumor away using laser treatment, or placement of a flexible tube (or stent) inside the esophagus to maintain the swallowing passage.
The likelihood of being cured of cancer depends in large part on the stage of the cancer at the time it is diagnosed. From 80% to 90% of patients with the earliest stage of esophageal cancer can expect to be alive and cancer free 5 years after treatment. However, since the typical esophageal cancer is discovered at a relatively advanced stage, the overall success rate in curing esophageal cancer is disappointing.