BRAFV600 mutations in solid tumors, other than metastatic melanoma and papillary thyroid cancer, or multiple myeloma: a screening study

Abstract

Allen L Cohn,1 Bann-Mo Day,2 Sarang Abhyankar,3 Edward McKenna,2 Todd Riehl,4 Igor Puzanov5 1Medical Research, Rocky Mountain Cancer Centers, Denver, CO, 2US Medical Affairs, 3Global Safety and Risk Management, 4Product Development Oncology, Genentech, Inc., South San Francisco, CA, 5Melanoma Section, Division of Hematology-Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA Background: Mutations in the BRAF gene have been implicated in several human cancers. The objective of this screening study was to identify patients with solid tumors (other than metastatic melanoma or papillary thyroid cancer) or multiple myeloma harboring activating BRAFV600 mutations for enrollment in a vemurafenib clinical study.Methods: Formalin-fixed, paraffin-embedded tumor samples were collected and sent to a central laboratory to identify activating BRAFV600 mutations by bidirectional direct Sanger sequencing.Results: Overall incidence of BRAFV600E mutation in evaluable patients (n=548) was 3% (95% confidence interval [CI], 1.7–4.7): 11% in colorectal tumors (n=75), 6% in biliary tract tumors (n=16), 3% in non-small cell lung cancers (n=71), 2% in other types of solid tumors (n=180), and 3% in multiple myeloma (n=31). There were no BRAFV600 mutations in this cohort of patients with ovarian tumors (n=68), breast cancer (n=86), or prostate cancer (n=21).Conclusion: This multicenter, national screening study confirms previously reported incidences of BRAFV600 mutations from single-center studies. Patients identified with BRAFV600 mutations were potentially eligible for enrollment in the VE-BASKET study. Keywords: genetic testing, proto-oncogene proteins B-raf, PLX4032

Keywords

• genetic testing
• proto-oncogene proteins B-raf
• PLX4032