Metastatic Colorectal Cancer Treatment

Researchers from the Dana Farber Cancer Institute in Boston retrospectively examined patterns of care and predictors of treatment approaches for 4,877 patients with metastatic colorectal cancer. Data entered into the Intellidose chemotherapy order entry system at academic, private, and community-based oncology practices across the United States between January 2004 and March 2011 were analyzed. The order entry system captured disease stage, patient demographics, provider characteristics, and chemotherapy regimen selection. Multivariable analyses were used to identify independent predictors of treatment decisions. Throughout the study period, a fluoropyrimidine/oxaliplatin combination was the most commonly used first-line chemotherapy regimen, representing 71% of first-line therapy by 2007. First-line bevacizumab use averaged 51% and peaked at 55% in 2006. Of those who received first-line bevacizumab, 34% continued to receive bevacizumab as second-line treatment.

Only 26% of patients received an anti-EGFR monoclonal antibody (cetuximab = 22%; panitumumab = 6%) at some point in their treatment course. Patients treated at academic centers, with longer duration of first-line therapy, and at sites in the western United States were statistically more likely to receive an anti-EGFR antibody. Anti-EGFR antibody use fell by 18% after the Food and Drug Administration limited its use to patients with KRAS wild-type tumors in June 2009. The researchers noted that even in academic centers, only 50% of patients were tested for KRAS mutations, and concluded that the study presents a portrait of real-world practice.

Reference Abrams TA, Meyer G, Schrag D, et al. Chemotherapy usage patterns in a US-wide cohort of patients with metastatic colorectal cancer. J Natl Cancer Inst (2014) 106 (2): djt371 doi: 10.1093/jnci/djt371