Changing patterns in the incidence of esophageal and gastric carcinoma in the United States.

BACKGROUND: Incidence rates for esophageal adenocarcinoma previously were reported to be increasing rapidly, especially among white males. Rates for gastric cardia adenocarcinoma also were observed to be rising, although less rapidly. In this article, the authors update the incidence trends through 1994 and further consider the trends by age group.
METHODS: Surveillance, Epidemiology, and End Results (SEER) program data were used to calculate age-adjusted incidence rates for esophageal carcinoma by histologic type and gastric adenocarcinoma by anatomic subsite.
RESULTS: Among white males, the incidence of adenocarcinoma of the esophagus rose > 350% since the mid-1970s, surpassing squamous cell carcinoma around 1990. Rates also rose among black males, but remained at much lower levels. To a lesser extent, there were continuing increases in gastric cardia adenocarcinoma among white and black males, which nearly equaled the rates for noncardia tumors of the stomach in white men. The upward trend for both tumors was much greater among older than younger men. Although the incidence also rose among females, rates remained much lower than among males.
CONCLUSIONS: Previously reported increases of esophageal adenocarcinoma are continuing, most notably among white males. Cigarette smoking may contribute to the trend through an early stage carcinogenic effect, along with obesity, which may increase intraabdominal pressure and predispose to gastroesophageal reflux disease. Further research into esophageal and gastric cardia adenocarcinoma is needed to clarify the risk factors and mechanisms responsible for the upward trends as well as the racial and gender disparities in incidence.