"Matching" the "Mismatch" Repair-Deficient Prostate Cancer with Immunotherapy.

Mismatch repair gene mutations are uncommon in advanced prostate cancer; however, in those harboring these alterations, immune checkpoint blockade can be effective. As such, assays that can accurately identify these men are critically important. Cell-free circulating tumor DNA-based sequencing approaches appear to be one viable approach for identifying these patients.See related article by Ritch et al., p. 1114. ©2020 American Association for Cancer Research.