Results of preoperative antitumor therapy in combination with bevacizumab and KRAS status during liver resections for colorectal cancer metastases

Abstract

Whether it is expedient and safe to add bevacizumab to preoperative treatment regimens for colorectal cancer liver metastases has been remained unclear over many years in spite of the duration of its use in this category of patients. In our trial, incorporation of bevacizumab into preoperative therapy was also accompanied by an increase in disease control and a significant reduction in the risk of disease progression during chemotherapy versus other treatment regimens. Comparison with a subgroup of patients treated with oxaliplatin-based regimens without bevacizumab showed that the significance of their difference disappeared; however, a clear trend persisted in favor of bevacizumab addition. KRAS is the only molecular marker used to select patients for therapy with monoclonal antibodies. Our findings also suggest that particular emphasis should be laid on the KRAS status in patients receiving bevacizumab therapy. Random estimation of the KRAS status in the patients who had undergone successful preoperative therapy and liver resection displayed a clear tendency towards the prevalence of the wide-type gene as compared with population-wide data.

Keywords

• k-ras
• metastatic colorectal cancer
• bevacizumab
• liver resection
• kras
• conversion antitumor therapy