To the Editor The article by Pearlman et al1 broaches a matter of high importance; 1 in 6 patients with a diagnosis of early-onset colorectal cancer (CRC) carries a germline defect in a known cancer susceptibility gene. Of these, 1 in 8 carries a CRC-predisposing allele while 3% of the individuals tested carried mutations in breast cancer genes with high or moderate penetrance. These might be simply incidental findings and although they can be clinically actionable for the individuals themselves and their families, a direct association with CRC predisposition has not been established.
Fostira F, Papaconstantinou I. Mutation Frequencies in Patients With Early-Onset Colorectal Cancer. JAMA Oncol. Published online July 06, 2017. doi:10.1001/jamaoncol.2017.0037