Research In Early Efficacy Of Patients With Potentially Resectable Metastatic Colorectal Cancer In Bevacizumab Therapy

Objective:To evaluate early efficacy and conversion therapy of bevacizumab combined with chemotherapy in the treatment of potentially resectable metastatic colorectal cancer, analyze the clinical benefit of applications of bevacizumab.Methods:Patients with metastatic colorectal cancer in our hospital from Jan.2013to Jan.2014were analyzed with their Lesions progress and treatment features. Every patients receive KRAS testing, bevacizumab combined with chemotherapy according to NCCN Guidelines (chemotherapy includes XELOX, mFOLFOX6, FOLFIRI, etc. and before chemotherapy they take bevacizumab7.5mg/Kg (every three weeks) or5mg/kg (every two weeks). Evaluate their treatment effect two months after chemotherapy.Results:33patients are able to be evaluated. Objective response rate was66.7%. Disease control rate was97.0%,22(66.7%) achieved partial response (PR) and10 patients (30%) had stable disease (SD).2(66.7%) achieved partial response (PR) in Wild-type KRAS,12(80%) achieved partial response (PR) in KRAS mutations.8(80%) achieved partial response (PR) with FOLFIRI,9(60%) achieved partial response (PR) with mFOLFOX6and5(70.1%) achieved partial response (PR) with XELOX. Toxicity of chemotherapy related reactions include bone marrow suppression, gastrointestinal reactions, neurotoxicity, and liver dysfunction. Targeted medicine therapy related reactions include hypertension, bleeding, proteinuria. No thrombosis, embolism, and wound dehiscence. Eight patients are up to the standard of conversion surgery, including5patients received R0resection, R0resection rate was62.5%.Conclusion:1. Metastatic colorectal cancer patients treated by bevacizumab have a significant early period clinical benefits, but it doesn’t mean that bevacizumab gives patients longer PFS.2. There was no significant difference between the bevacizumab effect of Wild-type KRAS and KRAS mutations.3. bevacizumab combined with irinotecan chemotherapy was better than it combined with oxaliplatin.4. Bevacizumab combined with chemotherapy provide higher R0resection rate for conversion therapy.