Double-blind, placebo-controlled, randomised trial of octreotide in malignant bowel obstruction

Context Does octreotide reduce vomiting in cancer-associated bowel obstruction? Objectives To evaluate the net effect of adding octreotide or placebo to standardized therapies on the number of days free of vomiting for populations presenting with vomiting and inoperable bowel obstruction secondary to cancer or its treatment. Methods Twelve services enrolled people with advanced cancer presenting with vomiting secondary to bowel obstruction where surgery or anti-cancer therapies were not indicated immediately. In a double-blind study, participants were randomized to placebo or octreotide (600mcg/24hours by infusion). Both arms received standardized supportive therapy (infusion of ranitidine [200mg/24hours], dexamethasone [8mg/24hours] and parenteral hydration [10-20mls/kg/24hours]). The primary outcome was patient-reported days free of vomiting at 72 hours. Results In a study that recruited to the numbers identified in its power calculation, 87 participants provided data at 72 hours (45, octreotide arm). Seventeen people (octreotide) and 14 (placebo) were free of vomiting for 72 hours. (P = 0.67). Mean days free of vomiting were 1.87 (SD 1.10; octreotide) and 1.69 (SD 1.15; placebo); P = 0.47). An adjusted multivariable regression of the incidence of vomiting over the study showed a reduced number of episodes of vomiting in the octreotide group (IRR = 0.40; 95% CI 0.19, 0.86; P = 0.019); however, people in the octreotide arm were 2.02 times more likely to be administered hyoscine butylbromide (P = 0.004) potentially reflecting increased colicky pain. Conclusion Although there was no reduction in the number of days free of vomiting, the multivariable analysis suggests that further study of somatostatin analogues in this setting is warranted.