Ranitidine as adjuvant treatment in colorectal cancer

Results from short-term studies of histamine type 2 (H2) receptor antagonists on survival of patients with solid tumours are debatable. In this study the efficacy of the H2-receptor antagonist ranitidine on long-term survival of patients with colorectal cancer was evaluated.

Patients scheduled for elective resection of primary tumours were consecutively included in a randomized double-blind placebo-controlled clinical study designed to evaluate the effect of ranitidine on survival. Before skin incision ranitidine 100 mg or placebo was given intravenously twice daily followed by oral ranitidine 150 mg or placebo twice daily for 5 years. Adjuvant cytotoxic or radiation therapy was not given. An observer-blinded interim analysis performed after 40 months showed that there was no effect of ranitidine on overall survival, and the study was discontinued in accordance with the protocol. The patient cohort has been followed continuously without loss of any patient, and a final statistical analysis was performed on an intention-to-treat basis after more than 5 years; this included a subgroup analysis of perioperative blood transfusion and postoperative infectious complications.

The median observation period of the 740 patients included was 6.8 (range 5.4-7.9) years. A univariate analysis of all 740 patients and of the subgroup of 560 who underwent curative resection showed no significant effect of ranitidine on survival. Furthermore, ranitidine had no survival benefit in curatively resected patients who received a perioperative blood transfusion (n = 358), but it improved the survival of non-transfused patients (n = 202; hazard ratio (HR) 0.6 (95 per cent confidence interval (c.i.) 0.4 to 0.9), P = 0.02) and of non-transfused patients who did not develop postoperative infectious complications (n = 170; HR 0.6 (95 per cent c.i. 0.4 to 0.9), P = 0.01). In multivariate analysis of patients who had a curative resection, including Dukes' stage, age, gender, tumour location, blood transfusion, postoperative infectious complications and treatment, ranitidine still had an independent, beneficial effect on survival (HR 0.6 (95 per cent c.i. 0.4 to 1.0), P = 0.04) within the subgroup of patients who did not receive perioperative blood transfusion and did not develop postoperative infectious complications.

Ranitidine may prolong the survival of patients who undergo curative resection of colorectal cancer and who do not receive perioperative blood transfusion and do not develop postoperative infectious complications.