The survival of patients who have cancers of the gastrointestinal tract is poor even after surgical resection of all gross disease. In an initial consecutive series of patients with metastatic or recurrent cancers, an attempt to improve survival with combined nonspecific immunostimulation by the intraperitoneal administration of BCG followed by oral BCG cycled with chemotherapy was studied. The results suggested that a population of patients with gastric and colonic cancers showed improved survival with this treatment. A randomized trial of combined chemoimmunotherapy versus chemotherapy alone was begun on November 1, 1974, for all cancers of the stomach and pancreas and all colorectal cancers beyond stage C by Dukes' classification. The initial results with patients entered by December 31, 1975, and followed until March 1, 1976, are reported.