IGF1R and bone metastasis: To evaluate the fraction of patients who may benefit from receiving anti-IGF-1R therapy in combination with ADT, or at later stages in combination with therapies given for castration-resistant prostate cancer (CRPCa), a series of bone metastasis biopsies from treatment-naïve (n = 14) and castration-resistant (n = 47) patients were evaluated for IGF-1R immunoreactivity.