Experimental studies have shown a significant inhibition of adenocarcinoma of the pancreas by gonadoliberin (luteinizing hormone-releasing hormone [LH-RH]) and somatostatin. The aim of this prospective randomized study was to compare the potential value of somatostatin (250 micrograms every 8 hours), LH-RH (3.75 mg monthly), or combined, to a control group. One hundred sixty-three patients with adenocarcinoma of the pancreas who did not undergo resection for cure were divided into 4 groups that did not differ in terms of clinical, biologic, or pathologic data. The mean survival times were 6 months in the LH-RH plus somatostatin group, 5.5 months in the LH-RH group, 4.3 months in the control group, and 3.8 months in the somatostatin group. However, the life-table analyses for all randomized patients, and separately according to sex, the lymph node extension, and metastatic spread were not different between groups. Improvement of patient status was observed in 20% of the patients receiving hormone therapy without any difference noted between the treatment regimens. These disappointing results may be explained by the degree of extension of pancreatic carcinoma in the patients studied. The results suggest that different hormone therapy regimens might be considered according to the age and the sex of patients, as well as to the presence or absence of hormone receptors.