The purpose of this study was to investigate the reasons for delayed diagnosis of gastric cancer in the Greek population and correlate survival with early or late diagnosis. We studied 100 patients with gastric cancer proven at endoscopy. Early diagnosis (less than 3 months from the onset of symptoms) was established in 28 patients (28%), while the diagnosis was late (greater than 3 months) in 72 patients (72%). The reasons for late diagnosis were: 1. delayed consultation on the part of the patient, 2. incorrect medical diagnosis at a) initial evaluation, b) radiological evaluation and, as a result, c) failure to refer for endoscopy and biopsy. Patient survival correlated well with tumor resectability, irrespective of early or late diagnosis. In patients with early diagnosis and resectable tumor survival was 9.9 +/- 4.8 months (mean +/- SD) whereas with non-resectable tumor 4.8 +/- 4.0 months (p less than 0.01). In patients with late diagnosis, survival in resectable tumor was 13.5 +/- 11.7 months compared with 8.5 +/- 6.9 months in non-resectable tumor. No correlation was noted between survival and anatomic location of tumor or degree of histologic differentiation. Early diagnosis of gastric cancer is associated with a higher degree of resectability and therefore of better survival.