What is esophageal cancer?
The esophagus is a long, muscular tube that runs from the throat to the stomach. The esophagus is made up of several layers of muscle that contract to help move food down the tube and into the stomach. A special muscle called the esophageal sphincter acts as a valve, opening to allow food and liquids to pass from the esophagus into the stomach.
Esophageal cancer results when abnormal cells grow out of control in esophageal tissue. Eventually the cells form a mass called a tumor. There are two main types of esophageal cancer:
- Squamous cell carcinoma begins in the cells (called squamous cells) that line the esophagus. This cancer usually affects the upper and middle part of the esophagus.
- Adenocarcinoma develops in the tissue that produces mucus that aids in swallowing. It generally occurs in the lower part of the esophagus.
Rates of squamous cell carcinoma in the US have been falling, while adenocarcinoma rates have been rising.
How common is esophageal cancer?
Esophageal cancer is not common, although it ranks among the 10 most common cancers in the world. The number of new cases of this type of cancer is about 4.2 per 100,000 people in the U.S. The number of new cases is estimated to have been 17,290 in 2018, with the number of deaths estimated at 15,850 people.
The five-year survival rate for people diagnosed with this type of cancer was 19.2% for 2008-2014. There were about 47,284 people with esophageal cancer in the US in 2015, according to estimates.
What causes esophageal cancer?
The exact cause of esophageal cancer is not known, but there are several risk factors for the disease. Risk factors for esophageal cancer include:
- Older age: Esophageal cancer occurs more often in people older than 60 years than in those aged 60 or younger.
- Male gender: Men are three times more likely to develop the disease than women.
- Ethnicity: Squamous cell esophageal cancer happens more often in African Americans and Asians. Adenocarcinoma happens more often in whites.
- Tobacco use: This includes smoking and using smokeless tobacco.
- Alcohol use: Chronic and/or heavy use of alcohol increases the risk of esophageal cancer.
- Barrett’s esophagus and chronic acid reflux: Barrett’s esophagus is a change in the cells at the lower end of the esophagus that occurs from chronic untreated acid reflux. Even without Barrett’s esophagus, people with long-term heartburn have a higher risk of esophageal cancer.
- Human papilloma virus (HPV): In areas of the world that have a high incidence of esophageal cancer (such as Asia and South Africa), infection with HPV carries an increased risk for developing esophageal squamous cell cancer. HPV is a common virus that can cause tissue changes in the vocal cords and mouth, and on the hands, feet and sex organs.
- Other disorders: Other conditions have been linked to esophageal cancer. These include achalasia, an uncommon disease that causes difficulty swallowing, and tylosis, a rare, inherited disorder in which excess skin grows on the palms of the hands and the soles of the feet.
- Occupational exposure to certain chemicals: People exposed to dry cleaning solvents over long periods of time are at higher risk for esophageal cancer.
- History of cancer: People who have had cancer of the neck or head have a greater risk for esophageal cancer.
What are the symptoms of esophageal cancer?
Esophageal cancer may have no obvious symptoms in its early stages. The symptom people notice first is difficulty swallowing. As the tumor grows, it narrows the opening of the esophagus, making swallowing difficult and/or painful. Other symptoms of esophageal cancer can include:
- Pain in the throat or back, behind the breastbone, or between the shoulder blades
- Vomiting or coughing up blood
- Hoarseness or chronic cough
- Unintentional weight loss