Effect of Diversion Ileostomy on the Occurrence and Consequences of Chemotherapy-Induced Diarrhea

The benefits of adjuvant chemotherapy in the treatment of colorectal cancer are well established. Chemotherapy-induced diarrhea is a common adverse effect of these regimens. The occurrence of chemotherapy-induced diarrhea not only directly affects patient health but may also compromise treatment efficacy because of consequent dosing alterations or discontinuation.This study aimed to investigate the effect of diverting loop ileostomy during chemotherapy on the occurrence and consequences of chemotherapy-induced diarrhea.This was a retrospective evaluation of a prospective surgical database.This was a single-institution retrospective study.All patients receiving curative adjuvant chemotherapy after anterior resection for colorectal cancer at Auckland Hospital from 2002 to 2013 were retrospectively evaluated.Patient-, perioperative-, and chemotherapy-related variables were collected. Chemotherapy-induced diarrhea occurrence was graded according to National Cancer Institute Common Terminology Criteria for Adverse Events. Logistic regression analysis was performed to identify independent predictors for chemotherapy-induced diarrhea occurrence, treatment modifications, and hospital admission.A total of 109 identified patients received 691 chemotherapy cycles; 84% of patients with a diverting ileostomy experienced chemotherapy-induced diarrhea compared with 47% in those who were not defunctioned (p < 0.01). On logistic regression analysis, the presence of a diverting ileostomy during chemotherapy was an independent predictor of chemotherapy-induced diarrhea grade 3 or higher (OR, 13.6 (95% CI: 1.2-150.9); p = 0.02), the need for a dosing reduction (OR, 4.0 (95% CI: 1.3-12.4); p = 0.02), and the need for any modification in the chemotherapy regimen (OR, 3.4 (95% CI: 1.2-9.6); p = 0.02).This study is limited by its retrospective design, potentially limiting the accuracy of chemotherapy-induced diarrhea grade reporting.The presence of an ileostomy during adjuvant chemotherapy is a predictor of severe chemotherapy-induced diarrhea and the need for modifications in the chemotherapy regimen. This may have important consequences for long-term survival. Prospective investigation is needed to further assess the impact of diverting ileostomy on the delivery of chemotherapy and oncologic outcomes.