FOXA1 and Familial prostate cancer: FOXA1 is also commonly mutated in cancer, with mutations observed in 9–11% of primary prostate cancers, up to 13% of metastatic prostate adenocarcinomas, and up to 25% of NEPC (Adams et al. 2019, Parolia et al. 2019, Beltran et al. 2020).