Purpose: This prospective observational study assessed the efficacy of bevacizumab in combination with chemotherapy as preoperative treatment to downsize tumours for radical resection in patients with unresectable metastatic colorectal cancer (mCRC).
Patients/methods: Patients with mCRC initially unresectable according to predefined criteria were included. Preoperative treatment consisted of bevacizumab (5 mg/kg) combined with oxaliplatin- or irinotecan-based chemotherapy, which was followed by surgery in patients showing clinical benefit. Resection rate was the primary endpoint. Response rate (RR) and clinical benefit of preoperative chemotherapy, and overall survival (OS) were secondary endpoints.
Results: A total of 120 eligible patients were included and received preoperative treatment. Chemotherapy was irinotecan-based in 73 (61 %) patients, oxaliplatin-based in 25 (21 %) and 22 (18 %) patients received more than one line. A RR of 30 % and a clinical benefit rate of 73 % were observed with preoperative chemotherapy. Metastatic resection was possible in 61 (51 %) patients. Median OS was 33 months (95 % CI 31-NA months) for patients undergoing surgery, and 15 months (95 % CI 11-25 months) in non-operated patients. Thirty-five patients experienced 59 postoperative complications (morbidity rate 57 %).
Conclusion: Preoperative bevacizumab-based chemotherapy offers a high surgical rescue rate in patients with initially unresectable mCRC.