Improved technology has made it possible to test for mutations within multiple genes simultaneously. It is not clear when these gene 'panels' should be used in the hereditary cancer setting. These analyses were intended to guide panel testing criteria. Offering hereditary panel testing as a first and final, 'single-tier', option was explored. A 'two-tiered' approach, in which panel testing is offered reflexively following stricter criteria, was then applied to the same data. Within our cohort of 105 patients, the single-tier approach was associated with a higher mutation detection rate (6.7% vs 3.8%) and variant of uncertain significance (VUS) rate (0.94 vs 0.23 average per person) compared to a two-tiered approach. Of the VUSs also identified in other patients by another lab, 53% were classified differently between laboratories. Individuals reporting African American race had more VUSs compared to other ancestry groups (p = 0.001). The test cost for a single-tier test was 21% more than a two-tiered approach. Single-tier panel testing was associated with higher mutation and VUS rates, and there is inconsistent classification of the VUS/low penetrant genes between laboratories.
Keywords: hereditary cancer; next-generation sequencing; panel testing.
© 2014 The Authors. Clinical Genetics published by John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.