OBJECTIVES: Determine the 5-year survival rate, prognostic factors, postoperative morbidity and mortality rates and the accuracy of the Maruyama computer program.MATERIAL and METHODS: This prospective study evaluated 32 patients with advanced gastric adenocarcinoma underwent radical gastrectomy with D2 (n= 13) or D3-D4 (n= 19) extended lymphadenectomy, at Belen Hospital, Trujillo, Peru, from 1990 to 1998.RESULTS: Gastric cancer patients (20 F: 12 M) had a median age of 55.4 + 14.5 years (range, 20 to 76 years). In D3-D4 patients there was a significant increased in the number of cases with lesions type Borrmann III-IV (p= 0.03), N3 (p= 0.04), M1 (p= 0.04) and undifferentiated type in histology (p= 0.04) compared with D2 cases. The 5-year survival in curative and palliative surgery was of 48.9% and 10.7%, respectively (p<0.001). The 5-year survival in D2 surgery was of 42.7% and in D3-D4 was of 27.6% (p= NS). The 5-year survival rate in the total series was of 30.9%. Location (p< 0.05) and size of the tumor (p< 0.01), distant metastases (p< 0.05), clinical stage (p< 0.05), Borrmann's type (p< 0.05) and curability (p< 0.05) were factors that influenced long-term survival. The morbidity rate with D2 and D3-D4 disection was of 30.7% and 57.8%, respectively (p= NS), and in the total series was of 46.8%. The mortality rate in this series was of 3.1%. The prediction of the lymphs node metastases with the computer program was highly exact (13-16: 100%, 7-12: 75%, 1-6: 66%).CONCLUSIONS: Extended lymphadenectomy had a low surgical mortality but high morbidity and permitted that one third of advanced gastric cancer patients underwent surgery obtains 5-year survival.