Treatment with cetuximab, bevacizumab and irinotecan in heavily pretreated patients with metastasized colorectal cancer

Abstract

Background: Modern therapy algorithms for advanced colorectal cancer include the monoclonal antibodies bevacizumab and cetuximab. Routinely, these antibodies are given sequentially in combination with chemotherapy. The question whether a combination of bevacizumab and cetuximab is beneficial has not been answered. The results of the BOND-2 study showed that tumor drug resistance to irinotecan can be overcome by addition of both cetuximab and bevacizumab.

Patients and methods: Here, we present the cases of five patients who were heavily pretreated and already had received cetuximab (and in two cases also bevacizumab). These patients received a chemotherapeutic regimen consisting of irinotecan, cetuximab and bevacizumab.

Results: The combination of these two antibodies with irinotecan surprisingly induced marked tumor response in four out of five patients.

Conclusion: There are currently no published data concerning the question whether resistance against one monoclonal antibody can be overcome by the addition of another monoclonal antibody. These cases point to a possible novel treatment approach and provide an incentive for further experimental investigations. The treatment was well tolerated and should be considered as a further medical treatment strategy.