One hundred sixty consecutive cases of esophageal and gastric carcinoma were reviewed to evaluate the impression of recent changes in their types and characteristics. Esophageal adenocarcinomas accounted for 34 per cent of all esophageal cancers and 60 per cent of tumors confined to the lower third of the esophagus; all but one were associated with Barrett's epithelium. Among the gastric cancers, previous observations of an increased prevalence of neoplasms confined to the cardia were extended. Proximal adenocarcinomas (arising from the esophagus, gastroesophageal junction, and cardia) constituted 34 per cent of all adenocarcinomas in this series and appeared to be a distinctive group with common features. Compared with other gastric cancers, the proximal carcinomas were associated with a lower mean age (65 years), higher male-to-female ratio (3.3:1), greater frequency of hiatal hernia (40 per cent), greater incidence of smoking and alcohol use, and lower prevalence of tumors composed predominantly of signet ring cells. Thus, proximal adenocarcinomas may form a specific category etiologically different from distal gastric cancers.