A risk factor is anything that changes your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, unprotected exposure to strong sunlight is a risk factor for skin cancer, and smoking is a risk factor for lung cancer as well as many others. Scientists have found several risk factors that affect your risk of cancer of the esophagus. Some are more likely to increase the risk for adenocarcinoma of the esophagus and others for squamous cell carcinoma of the esophagus.

Age

The chance of getting esophageal cancer is low at younger ages and increases with age. Less than 15% of cases are found in people younger than age 55. Most cases occur in those 65 and older.

Gender

Compared with women, men have a 3-fold higher rate of esophageal cancer.

Gastroesophageal reflux disease

In some people, acid can escape from the stomach into the esophagus. The medical term for this is reflux or gastroesophageal reflux disease (GERD). In many cases, reflux causes symptoms such as heartburn or pain that seems to come from the middle of the chest. In some cases, though, reflux doesn't cause any symptoms at all. People with GERD have a risk of getting adenocarcinoma of the esophagus that is 2 to 16 times normal. The risk goes up based on how long the reflux has been going on and how severe the symptoms are. GERD can also cause Barrett's esophagus, which is linked to an even higher risk (discussed below). About 30% of esophageal cancer can be linked to GERD.

Barrett's esophagus

If reflux of stomach acid into the lower esophagus continues for a long time, it can damage the lining of the esophagus. This causes the squamous cells that usually line the esophagus to be replaced with glandular cells. These glandular cells usually look like the cells that line the stomach and the small intestine, and are more resistant to stomach acid. This condition is known as Barrett's (or Barrett) esophagus. About 10% of people with symptoms of gastroesophageal reflux disease (GERD) have this condition. The longer someone has GERD, the more likely that they have Barrett's esophagus. Most people with Barrett's esophagus have had symptoms of "heartburn," but many have no symptoms at all. Barrett's esophagus increases the risk of adenocarcinoma of the esophagus. This is because the gland cells in Barrett's esophagus can become more abnormal over time until they become dysplasia, a pre-cancerous condition. Dysplasia is graded by how abnormal the cells look like under the microscope. High-grade dysplasia is the most abnormal. People with Barrett's esophagus are anywhere from 30 to 125 times more likely than people without this condition to develop esophageal cancer. Still, many people with Barrett's esophagus do not get esophageal cancer. The exact risk of developing cancer in people with Barrett's esophagus is not known, but researchers estimate it to be only 1 in 200 per year.

Tobacco and alcohol

The use of tobacco products, including cigarettes, cigars, pipes, and chewing tobacco, is a major risk factor for esophageal cancer. The risk goes up with increased use -- the more cigarettes smoked per day and the longer a person uses tobacco, the higher the cancer risk. Someone who smokes at least a pack a day has twice the chance of getting adenocarcinoma of the esophagus than a nonsmoker. The link to squamous cell esophageal cancer is even stronger, with more than half of all cases linked to smoking. The risk of esophageal cancer improves if tobacco use stops.

Drinking alcohol also increases the risk of esophageal cancer. The chance of getting esophageal cancer goes up with higher intake of alcohol. Alcohol affects the risk of the squamous cell type more than the risk of adenocarcinoma.

Combining smoking and drinking alcohol raises the risk of esophageal cancer much more than using either alone.

Obesity

People who are overweight or obese have a higher chance of getting adenocarcinoma of the esophagus. This is in part explained by the link between obesity and esophageal reflux.

Diet

A diet high in fruits and vegetables is linked to a lower risk of esophageal cancer. Eating these foods raw has the best effect on risk. Fruits and vegetables provide a number of vitamins and minerals that may help prevent cancer. About 15% of esophageal cancer can be linked to a diet poor in fruits and vegetables. Certain substances in the diet may increase the cancer risk. This may explain the high rate of this cancer in certain parts of the world. There have been suggestions, as yet unproven, that a diet high in processed meat may also increase the chance of developing esophageal cancer.

Overeating, which leads to obesity (being extremely overweight), increases the risk of the adenocarcinoma of the esophagus.

Frequent drinking of very hot liquids may increase the risk for the squamous cell type of esophageal cancer.

Workplace exposures

Exposure to the solvents used for dry cleaning may lead to a greater risk of esophageal cancer. Dry cleaning workers have a higher rate of esophageal cancer. Exposure to other chemical fumes also may lead to an increased risk of esophageal cancer.

Injury to the esophagus

Lye is a chemical found in strong industrial and household cleaners such as drain cleaners. Lye is a corrosive agent, meaning it can burn and destroy cells. Sometimes small children find a lye-based cleaner and drink from the bottle. The lye causes a severe chemical burn in the esophagus. As the injury heals, the scar tissue can cause an area of the esophagus to become very narrow (called a stricture). People with these strictures have a high rate of the squamous cell type of esophageal cancer as adults. The cancers occur on average about 40 years after the lye was swallowed.

Achalasia

In this disease, the muscle at the lower end of the esophagus (the lower esophageal sphincter) does not relax properly. Food and liquid that are swallowed have trouble passing into the stomach and tend to collect in the esophagus. The esophagus above this muscle becomes dilated (larger). People with achalasia have a risk of esophageal cancer that is at least 15 times normal. About 6% (1 in 20) of all achalasia patients develop squamous cell cancer of the esophagus. On average, the cancers are found about 17 years after the achalasia is diagnosed.

Tylosis

This is a rare, inherited disease that causes excess growth of the top layer of skin on the palms of the hands and soles of the feet. People with this condition develop abnormal areas in the lining of the mouth. They also have a very high risk of getting squamous cell cancer of the esophagus. People with tylosis are watched closely to try to find esophageal cancer early. Often this involves regular monitoring with an upper endoscopy (scope with camera placed to view the esophagus). This disorder is linked to a gene on an area of chromosome 17 called TOC.

Esophageal webs

A web is an abnormal bulge of tissue that causes an area of narrowing in the esophagus. This can lead to a feeling like food gets stuck when it is swallowed. When an esophageal web is found along with anemia, tongue irritation (glossitis), brittle fingernails, and a large spleen it is called Plummer-Vinson syndrome. Another name for this is Paterson-Kelly syndrome. About 1 in 10 patients with this syndrome eventually develop squamous cell cancer of the esophagus.

Stomach bacteria

A certain bacteria called H. pylori can cause many stomach problems, including ulcers and even some types of cancer. Infection with this bacteria can be treated with antibiotics plus a drug to stop stomach acid. People who have had treatment to rid the stomach of H. pylori get adenocarcinoma of the esophagus more often than expected. It seems that H. pylori infection can cause the stomach to make less acid. The lower levels of acid mean that the stomach contents are less harmful to the esophagus (in people with reflux). The infection causes many problems in the stomach, but it may actually protect the esophagus.

Other cancers

People who have had certain other cancers, such as lung cancer, mouth cancer, and throat cancer have a high risk of getting esophageal cancer as well. This may be because these cancers are all caused by smoking.

Last Medical Review: 05/04/2009
Last Revised: 05/13/2009