Risk Factors and Adequate Management for Complications of Bevacizumab Treatment Requiring Surgical Intervention in Patients With Metastatic Colorectal Cancer.

BACKGROUND: Bevacizumab (BV) has been approved for treating colorectal cancer since 2004. Although BV use may lead to adverse effects, few studies have reported incidences requiring surgical intervention. We aimed to identify the risk factors and adequate interventions for complications requiring surgical intervention after BV treatment.

PATIENTS AND METHODS: We retrospectively reviewed the records of patients with metastatic colorectal cancer treated with BV in our institute from January 2009 to December 2016. The baseline patient characteristics were used to evaluate the potential risk factors for complications requiring surgery.

RESULTS: Of the 1008 patients recruited for this study, 60 (5.9%) experienced complications necessitating surgery after BV therapy. Gastrointestinal perforation was the most frequently observed complication, occurring in 36 patients (3.5%), and diverting colostomy was the most commonly performed intervention (22 patients, 36.6%). Multivariate analysis helped identify poor differentiation, signet ring cell carcinoma, stent insertion status, rectal location of the primary tumor, and intact primary tumor status as the risk factors. Survival time remained unchanged regardless of a complication that required surgery.

CONCLUSION: Careful monitoring during BV treatment for metastatic colorectal cancer is essential for patients who have a predisposition to complications that may require surgery. After detection, adequate and timely surgical management is imperative for ensuring patient survival.