Successful case of olaparib treatment for castration-resistant prostate cancer with multiple DNA repair gene mutations: Use of comprehensive genome profiling for treatment-refractory cases

Abstract

Herein, we report a case of a 59-year-old man with advanced castration-resistant prostate cancer with rectal invasion. Multimodal treatment, including drug therapy, surgery, and radiation therapy was sequentially performed; however, lymph node metastases repeatedly occurred. Tumor genomic profiling using FoundationOne CDx identified pathogenic alterations in three DNA repair genes, including BRCA2 frameshift mutation. Olaparib, a poly-ADP ribose polymerase inhibitor, showed marked response. Castration-resistant prostate cancer with multiple DNA repair genes was successfully treated with olaparib; comprehensive genome profiling can lead to its optimal clinical management.