Addition of Cetuximab Beneficial in Metastatic Colorectal Cancer

the Cancer Therapy Advisor take:

According to a new study published in the Journal of Clinical Oncology, researchers have found that patients metastatic RAS wild-type colorectal cancer derived a significant benefit from the addition of cetuximab to fluorouracil, leucovorin, and irinotecan (FOLFIRI) as first-line treatment, while those with RAS tumors did not.

The phase III CRYSTAL study found that the addition of cetuximab to FOLFIRI significantly improved objective response, progression-free survival, and overall survival in the first-line treatment of patients with KRAS codon 12/13 (exon 2) wild-type metastatic colorectal cancer, but researchers sought to perform subgroup analyses to determine if those with RAS wild-type tumors particularly benefit from the addition of immunotherapy. 

Researchers detected other RAS mutations in 14.7% of 430 evaluable patients with KRAS exon 2 wild-type tumors. They found that those with RAS wild-type tumors had significantly improved overall survival, progression-free survival, and objective response from the addition of cetuximab to FOLFIRI.

However, patients with other RAS tumor mutations did not improved efficacy outcomes. The findings suggest that patients with KRAS exon 2 wild-type tumors should be tested for all activating RAS mutations before healthcare providers consider cetuximab therapy in order to identify those patients that will benefit the most.