Genomic Profiling for KRAS, NRAS, BRAF, Microsatellite Instability, and Mismatch Repair Deficiency Among Patients With Metastatic Colon Cancer

Martin E Gutierrez 1, Kristin S Price 2, Richard B Lanman 2, Rebecca J Nagy 2, Irfan Shah 3, Shivam Mathura 3, Michael Mulcahy 3, Andrew D Norden 3, Stuart L Goldberg 1 3

Affiliations

PMID: 32923867
PMCID: PMC7448804 (available on 2020-12-06)
DOI: 10.1200/PO.19.00274

Abstract

Purpose: Genomic testing is recognized in national guidelines as essential to guide appropriate therapy selection in metastatic colorectal cancer. Previous studies report adherence to testing guidelines is suboptimal, but current testing rates have not been assessed. This study reports testing rates in metastatic colon cancer (mCC) for guideline-recommended biomarkers in a US-based population.

Materials and methods: A retrospective review of data extracted from electronic medical records was performed to identify patients with pathologically confirmed mCC and describe patterns of guideline-aligned biomarker testing. Data were extracted from the electronic health records of 1,497 patients treated at 23 practices across the United States. Both community and academic centers were represented.

Results: A total of 1,497 patients with mCC diagnosed between January 1, 2013 and December 31, 2017 were identified. Guideline-aligned biomarker testing rates for RAS, BRAF, and microsatellite instability/mismatch repair deficiency over this study period were 41%, 43%, and 51%, respectively. Patients were more likely to have guideline-aligned testing for RAS and BRAF if they were treated at an academic center, were diagnosed with de novo metastatic disease, and were female. In addition, patients < 65 years of age were more likely to have guideline-aligned RAS testing. Of the 177 patients (12% of cohort) who received anti-epidermal growth factor receptor therapy, only 50 (28%) had complete guideline-aligned biomarker testing.

Conclusion: Despite guideline recommendations and significant therapeutic implications, overall biomarker testing rates in mCC remain suboptimal. Adherence to guideline-recommended biomarker testing would potentially reduce exposure to expensive and ineffective therapies, resulting in improved patient outcomes.

Conflict of interest statement

The following represents disclosure information provided by authors of this manuscript. All relationships are considered compensated unless otherwise noted. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/po/author-center. Open Payments is a public database containing information reported by companies about payments made to US-licensed physicians (Open Payments). Martin E. GutierrezStock and Other Ownership Interests: Cota Healthcare Honoraria: Foundation Medicine, Guardant Health Consulting or Advisory Role: Exenex Speakers' Bureau: Bristol-Myers Squibb, Merck, Eli Lilly Research Funding: Bristol-Myers Squibb (Inst), Merck (Inst), Incyte (Inst), NextCure (Inst), Pfizer (Inst), Genentech (Inst), Boehringer Ingelheim (Inst), GSB Pharma (Inst), Moderna Therapeutics (Inst), Eisai (Inst), Silenseed (Inst), Seattle Genetics (Inst), Regeneron (Inst), Sanofi (Inst), Johnson & Johnson (Inst), MedImmune (Inst), Checkpoint Therapeutics (Inst) Travel, Accommodations, Expenses: Guardant HealthKristin S. PriceEmployment: Guardant Health, Counsyl Stock and Other Ownership Interests: Guardant Health, CounsylRichard B. LanmanEmployment: Guardant Health, Veracyte Leadership: Guardant Health, Biolase Stock and Other Ownership Interests: Guardant Health, Biolase, Forward Medical Consulting or Advisory Role: Forward Medical Research Funding: Guardant HealthRebecca J. NagyEmployment: Guardant Health Stock and Other Ownership Interests: Guardant HealthIrfan ShahEmployment: Cota Healthcare Stock and Other Ownership Interests: Guardant HealthMichael MulcahyEmployment: Cota HealthcareAndrew D. NordenEmployment: Cota Healthcare, IBM Leadership: Cota HealthcareStuart L. GoldbergEmployment: Cota Healthcare Stock and Other Ownership Interests: Cota Healthcare Research Funding: Celator Pharmaceuticals (Inst), Bristol-Myers Squibb (Inst), Novartis (Inst) No other potential conflicts of interest were reported.