In Reply Regarding the deficiency in cell-free DNA (cfDNA) reports not reporting germ-line abnormalities, we1 certainly agree with Dr Sorscher. The current approach of ordering both a cfDNA test from one laboratory and a germ-line analysis from another is both inefficient and expensive. Indeed, patients with advanced disease can find themselves in a situation where the germ-line testing is reimbursed and the cfDNA is not, or vice versa. A combined germ-line and cfDNA somatic test makes particular sense in the setting of PARP inhibition, where a BRCA1/2 mutation may identify a patient with sensitive disease irrespective of whether the mutation is germ-line or somatic. A test that does not do both risks missing patients who could benefit.
Niravath P, Cakar B, Ellis M. Current Challenges Associated With Next-Generation Sequencing of Breast Cancer—Reply. JAMA Oncol. Published online May 18, 2017. doi:10.1001/jamaoncol.2017.0665