FIG 1.

Paired tumor/germline patients by prior testing and tumor screening history. Abnormal immunohistochemistry (IHC): abnormal IHC screening because of loss of expression of at least one mismatch repair (MMR) protein as reported on external final IHC result; weak/equivocal staining: MMR protein expression reported as weak, equivocal, attenuated, nearly absent, segmental, partial, focal, decreased, or indeterminate without complete loss of any other MMR proteins on external final IHC result. (*) Three patients submitted for paired testing were removed from additional analysis; two from group 1 because microsatellite instability (MSI) results from paired testing were microsatellite stable (MSS) and one from group 3 because MSI results from paired testing were MSI high (MSI-H). CRC, colorectal cancer; EC, endometrial cancer; MSI-L, low microsatellite instability.