Researchers aren't sure exactly why esophageal cancer is increasing, but it's easy to make some educated guesses. We know there is an association between:

• Gastroesophageal reflux disease (GERD), a common condition, and esophageal cancer.
• Barrett's esophagus and esophageal cancer. In Barrett's esophagus, the lining of the esophagus, which carries food and saliva from the mouth to the stomach, changes to a type of tissue usually found in the intestine.
• GERD and Barrett's esophagus, an uncommon condition.

Because obesity is a risk factor for GERD, the increasing girth of Americans probably contributes to the increased incidence of esophageal cancer. Heavy drinking and tobacco use are also risk factors.

A diagnosis of esophageal cancer is serious. Often no early symptoms appear, so it's not diagnosed until it's advanced, when treatment may be more difficult. Symptoms may include difficulty swallowing; unintentional weight loss; hoarseness; chronic cough; and pain in the throat, midchest or between the shoulder blades.

The cure rate is low. According to the National Cancer Institute, the incidence and mortality rates are about the same. Esophageal cancer affects about five in every 100,000 Americans.

When diagnosed early, chances of cure are increased and only surgery is recommended. If more advanced but still localized, esophageal cancer is treated by chemotherapy and radiation, followed by surgery.

Research is under way on new chemotherapy agents that show some promise. Other research focuses on new ways to combine radiation and chemotherapy; ways to boost the body's immune reactions; and the use of targeted therapies to stop cancer growth. There are also new endoscopic techniques being studied for the treatment of early-stage esophageal cancer. So far, there's no miracle drug or approach on the horizon.

Prevention plays a significant role for patients with Barrett's esophagus, which is diagnosed by upper gastrointestinal endoscopy and biopsy. Patients with Barrett's esophagus should be examined periodically for esophageal cancer. Acid-blocking drugs, which help GERD, may improve Barrett's esophagus. However, it is not clear if these drugs help reduce a patient's risk of subsequent cancer. Only a few people who have Barrett's esophagus — less than 1 percent per year — may develop esophageal cancer.