(HealthDay News) – The addition of bevacizumab to combination chemotherapy for the treatment of stage IV colorectal cancer increases overall survival, particularly for patients receiving irinotecan-based chemotherapy regimens, but is associated with increased rates of strokes and gastrointestinal (GI) perforations, according to a study published online January 17 in the Journal of Clinical Oncology.
Jeffrey A. Meyerhardt, MD, MPH, of the Dana-Farber Cancer Institute in Boston, and colleagues analyzed data from 2,526 patients diagnosed with stage IV colorectal cancer between 2002 and 2007 and identified through the Surveillance, Epidemiology, and End Results-Medicare linked database. The patients received first-line combination chemotherapy with a fluoropyrimidine and either irinotecan (33%) or oxaliplatin (67%), and 36% received bevacizumab in combination with first-line therapy.
The researchers found that the addition of bevacizumab was associated with improved overall survival (adjusted hazard ratio [HR], 0.85). For patients receiving irinotecan-based chemotherapy, the survival advantage was more apparent than for those receiving oxaliplatin-based chemotherapy (HR, 0.80 and 0.96, respectively). The addition of bevacizumab to combination chemotherapy was significantly associated with increased risk of stroke (4.9 versus 2.5) and GI perforation (2.3 versus 1%). There was no increase in the risk of cardiac events and venous thrombosis with bevacizumab.
“The addition of bevacizumab to cytotoxic combination chemotherapy was associated with small improvement in overall survival as well as increased risk of stroke and perforation, but not cardiac events, among Medicare beneficiaries with stage IV colorectal cancer,” the authors write.
One author disclosed a financial relationship with the pharmaceutical industry.