Esophageal Cancer On the Rise
The past 25 years have seen the rates of some cancers fall, thanks to better
prevention efforts. During the same period, though, the frequency of some
esophageal cancers rose dramatically. The cause of this increase remains a
mystery, although important risk factors have been identified.
Understanding the causes of esophageal cancer, and changing a few simple
habits can reduce your risk for this uncommon but dangerous disease.
Two Faces of Esophageal Cancer
The esophagus is the tube that carries food from the mouth to the stomach.
This year, about 14,550 people will be diagnosed with cancer of the esophagus.
There are two major kinds of esophageal cancer:
- Squamous cell cancer
Their names refer to different types of cells in the esophagus that turn
into cancer. The two kinds of esophageal cancer have different causes, and
affect different parts of the esophagus. Once cancer is present, though,
the two kinds of esophageal cancer act similarly.
Squamous cell cancer
Middle portion of the esophagus
Where the esophagus meets the stomach (lowest portion)
Most common causes
Barrett's esophagus (caused by acid reflux)
Groups commonly affected
African-American men, Asian-American men
Prognosis and treatment
About the same
Esophageal Cancer: A Mysterious Change
As recently as 1975, 75% of esophageal cancers were squamous cell cancers.
Since then, the pattern of esophageal cancer changed in a major way:
- The rate of squamous cell cancers has fallen slightly.
- Adenocarcinoma rates have risen dramatically. Adenocarcinoma struck
four people per million in 1975, but that rate rose to 23 people per million in
2001. This makes it the fastest-growing cancer in the U.S., according to the
National Cancer Institute.
- As a result, adenocarcinoma cases now outnumber squamous cell cancers. The
total rate of esophageal cancer has also risen.
"Clearly something has happened" to create the change, says Manjit Bains,
MD, a thoracic surgeon at Memorial Sloan-Kettering Cancer Center in New York.
As for why, though, "at this time there is more conjecture than facts."
Improved detection rates aren't the cause, according to researchers. Experts
believe some risk factor for adenocarcinoma must also be increasing--but can't
say what. A leading suspect: rising rates of obesity -- possibly causing a
higher incidence of reflux, which is a risk factor for adenocarcinoma,
according to Bains.
Esophageal Cancer Risk Factors
Numerous factors increase the risk for esophageal cancer:
- Age over 60
- Male sex
- Tobacco use
- Alcohol use
- Barrett's esophagus (see below)
- History of head or neck cancer
- Frequent drinking of very hot beverages
Different risk factors are important for each type of esophageal cancer:
- Squamous cell cancers: tobacco or alcohol use increase risk the most. More
than half of these cancers are linked to tobacco. Using both tobacco and
alcohol together raises the risk far more than using either alone.
- Adenocarcinomas: A condition called Barrett's esophagus contributes to this
form of esophageal cancer. Smoking doubles the risk of adenocarcinoma, but
alcohol doesn't play a role.