Background: Gastric cancer is the first cause of death due to malignant tumors in Chile. Its mortality rates have stabilized in the last two decades and its prognosis is closely associated to the degree of tumor invasion at tbe moment of surgery. Aim To study the frequency of gastric cancer among symptomatic patients subjected to all upper gastrointestinal endoscopy at a secondary care health center Patients and methods: All upper gastrointestinal endoscopies performed to patients derived from public primary care clinics were recorded, Results: in the study period, 4,145 endoscopies were done to 818 men and 2,128 women. Seventy one percent of patients were aged over 40 years of age. Fifty one carcinomas and one lymphoma were detected, Of these, 10 tumors were incipient. Thirty one patients were operated on and in 22 a total gastrectomy was performed. One patient, that required an esophageal resection, died, Conclusions: Gastric cancer was detected in 1.2% of symptomatic adult patients subjected to an tipper gastrointestinal endoscopy (Rev Med Chile 2001; 129: 749-55).