John Theurer Cancer Center Investigators Report Poor Colorectal Cancer Biomarker Testing Rates

What you need to know

Investigators at John Theurer Cancer Center (JTCC) at Hackensack University Medical Center are the first to report poor adherence to genomic profiling guidelines for four biomarkers of metastatic colorectal cancer used to predict response to therapy, choose the most effective treatment, and improve outcomes — showing that only 40% of patients had their tumors tested. The study was published online in the December 6, 2019 issue of JCO Precision Oncology, a publication of the American Society of Clinical Oncology (ASCO). Genomic testing is recognized in national guidelines as essential to guide appropriate therapy selection in metastatic colorectal cancer. The presence or absence of mutations in genes such as RAS (KRAS and NRAS) and BRAF and genetic changes called microsatellite instability (MSI) can predict how well a patient will respond to metastatic colorectal cancer therapies such as cetuximab, panitumumab, and immunotherapy with pembrolizumab. Investigators at JTCC retrospectively reviewed the COTA Real World Data database to identify patients with metastatic colorectal cancer diagnosed between 2013 and 2017.

Results

Among the 1,497 patients identified, testing for biomarkers according to the guidelines for RAS, BRAF, and MSI were 41%, 43%, and 51%, respectively. RAS and BRAF testing were more likely to be done in academic medical centers compared with community hospitals. Of 177 patients who received cetuximab or panitumumab — drugs indicated for the treatment of people with normal RAS genes — only 28% had undergone tumor testing for RAS status. The investigators noted that possible barriers to biomarker testing may include availability of tumor tissue, turnaround time, physician knowledge, cost and insurance issues, patient preferences, and patient eligibility for therapy based on overall health.