Overview

of Esophageal Cancer

Esophageal cancer is relatively uncommon and can be very deadly. Each year in the United States, there are roughly 17,000 individuals diagnosed with esophageal cancer and 15,000 deaths from the disease.1

The 5-year survival rate for all patients diagnosed with esophageal cancer is approximately 18%, with most survivors having cancer that has not spread outside the esophagus (stage 0-II). This low survival is due to a combination of factors including advanced age and poor overall health at diagnosis, the presence of local and distant spread of cancer at diagnosis, and the fact that most patients have some minimal residual cancer remaining after primary treatment with surgical resection.2

The esophagus is the muscular tube that conveys food from the back of the throat to the stomach. It is part of a person’s gastrointestinal (GI) tract. When a person swallows, the walls of the esophagus squeeze together to push food down into the stomach.  The connection of the esophagus to the stomach at the diaphragm is called the gastro-esophageal junction. The gastro-esophageal junction serves as a one-way valve to keep stomach contents from being refluxed or regurgitated back into the esophagus.

If stomach contents reflux back into the esophagus the surface lining can be damaged due to the acidity of these contents. One symptom of regurgitation of stomach contents into the lower esophagus is heartburn. Heartburn is often associated with a “hiatal hernia,” which is a condition where the upper part of the stomach pushes up above the diaphragm and into the chest. Normally, the esophagus is lined with squamous epithelial cells; however, when reflux occurs, these cells are replaced by columnar epithelium, which is prone to develop a type of cancer called adenocarcinoma. This phenomenon is known as Barrett’s esophagus.

There are 2 major types of esophageal cancer:

  • Squamous cell carcinoma. Typically starts in squamous cells that line the esophagus in the upper and middle part of the esophagus.
  • Adenocarcinoma. Begins in the glandular tissue in the lower part of the esophagus where the esophagus and the stomach come together.

Over the past two decades, there has been a dramatic increase in the incidence of adenocarcinomas, which now account for one-third to one-half of all esophageal cancers. Most of the adenocarcinomas of the lower esophagus are thought to arise in the setting of Barrett’s esophagus.

Outcomes of treatment for squamous cell cancer and adenocarcinoma of the esophagus are very similar, except for the responsiveness of the cancer to some chemotherapy drugs. The results of treatment of squamous cell cancer and adenocarcinoma are included together unless otherwise specified.1,2

Next: Symptoms & Signs of Esophageal Cancer

References


1 American Cancer Society. Cancer Facts & Figures 2017.

2 https://www.cancer.net/cancer-types/esophageal-cancer/introduction