Different Treatment Combos Including FOLFOX/FOLFIRI/Bevacizumab/Cetuximab Offer Same Survival in Colorectal Cancer

Treatment with the chemotherapy regimens FOLFOX or FOLFIRI paired with the targeted agents bevacizumab (Avastin®) or cetuximab (Erbitux®) offer the same outcomes in terms of survival among patients with advanced colorectal cancer. Therefore, healthcare providers suggest that of these 4 possible treatment combinations, the optimal regimen should be based on patient preference of potential side effects. These results were recently presented as a late-breaking abstract at the 2014 annual meeting of the American Society of Clinical Oncology (ASCO).

Metastatic colorectal cancer, or cancer that has spread from the colon to distant sites in the body, is often treated with chemotherapy and/or a targeted agent. Two commonly used chemotherapy regimens are referred to as FOLFIRI (5-fluorouracil, leucovorin and irinotecan) and FOLFOX (same as FOLFIRI except irinotecan is replaced with oxaliplatin).

Bevacizumab is an agent that cuts off, or reduces the blood supply available to cancer cells, and cetuximab is an agent that blocks signaling along a cellular pathway that is associated with cancer spread.

As these agents are all approved for metastatic colorectal cancer and the optimal regimen has not yet been establisehd, researchers recently initiated a clinical trial to compare these regimens in this patient population.

The recent trial included patients with metastatic colorectal cancer who did not have KRAS mutations. Patients were randomly treated with one of the four following treatment combinations: FOLFIRI/bevacizumab; FOLFIRI/cetuximab; FOLFOX/bevacizumab; or FOLFOX/cetuximab.

There were no significant differences in overall or progression-free survival between any of these 4 treatment combinations.
Further analysis of different subsets of patients is ongoing to determine whether specific patient or cancer characteristics might be associated with differing outcomes among therapeutic regimens.
The researchers stated that at this point, patients who are eligible for these treatment regimens may choose their therapy based upon side effects associated with each regimen. Patients should discuss all options with their healthcare providers.

Reference: Venook A, Niedzwiecki D, Lenz H-J et al. CALGB/SWOG 80405: Phase III trial of irinotecan/5-FU/leucovorin (FOLFIRI) or oxaliplatin/5-FU/leucovorin (mFOLFOX6) with bevacizumab (BV) or cetuximab (CET) for patients (pts) with KRAS wild-type (wt) untreated metastatic adenocarcinoma of the colon or rectum (MCRC). Proceedings from the 2014 annual meeting of the American Society of Clinical Oncology (ASCO). Late-breaking abstract LBA 3. Available at: Accessed June 6,2014.