There are two main types of esophageal cancer: squamous cell carcinoma (SCC) and esophageal adenocarcinoma (AC). Although esophageal AC is often under-recognized, it represents the eighth most common cancer worldwide, and incidence of the disease is steadily increasing.1 There are numerous factors that may lead to the development of esophageal AC; however, increased attention is being given to patients’ lifestyle choices, which can put them at increased risk for malignancy.
The incidence of esophageal AC in the United States increased from approximately 3.6 cases per 1 million in 1973 to 25.6 cases per million in 2006.2 At the same time, the incidence of esophageal SCC has declined. The increased incidence of esophageal AC is undoubtedly multifactorial, with both patient risk factors and improved diagnostics playing important roles. Esophageal AC is more common in men than in women as well as in whites compared with blacks. Most cases of esophageal AC develop in patients with Barrett’s metaplasia resulting from gastroesophageal reflux disease (GERD). In patients with long-standing GERD, the stratified squamous epithelium found in the distal esophagus transforms to columnar epithelium, which has malignant potential. Patients with chronic reflux who gradually develop Barrett’s metaplasia are sometimes asymptomatic, which can make detection and treatment extremely challenging. Additional risk factors for developing esophageal AC include smoking, obesity, and alcohol use. H. pylori infection and a history of cholecystectomy represent additional risk factors that have been implicated in the development of esophageal AC; however, the supporting data are not as conclusive.
The obesity epidemic has been identified as a major contributor to the increased incidence of esophageal AC. Although obesity is an important factor in western countries such as the United States, growing concern also exists in other countries with rising esophageal AC rates. A recent study by Kroep et al3 evaluated the esophageal AC trends in the United States, Spain, and the Netherlands. Interestingly, the authors found that, although obesity rates have increased in all three countries, the increase alone does not entirely explain the rising rates of esophageal AC. In addition, alcohol use did not correlate with the observed increased esophageal AC incidence, and smoking, as with obesity, did not contribute as much as previously thought.
Continued monitoring of worldwide trends in esophageal AC is needed in order to further identify risk factors that health care professionals should be aware of and relay to their patients. In the meantime, patients with existing potential risk factors for esophageal AC need to be closely followed and counseled on modifying their lifestyles.
- Jemal A, Bray F, Center MM, et al. Global cancer statistics. CA Cancer J Clin. 2011;61(2):69-90.
- Pohl H, Sirovich B, Welch HG. Esophageal adenocarcinoma incidence: are we reaching the peak? Cancer Epidemiol Biomarkers Prev. 2010;19(6):1468-1470.
- Kroep S, Lansdorp-Vogelaar I, Rubenstein JH, et al. Comparing trends in esophageal adenocarcinoma incidence and lifestyle factors between the United States, Spain, and the Netherlands. Am J Gastroenterol. 2014;109(3):336-343.