Other issues to further solve to completely define how PARPi can personalize and improve the actual standard of care of prostate cancer include: the better definition of these agents’ sensitivity in the context of specific mutations (BRCA1/2, ATM, non-canonical DDR genes), the relevance of germline versus somatic and monoallelic versus biallelic HRR genes’ mutations, understanding how the current combination strategies may help to overwhelm the PARP-inhibition resistance and the comparative efficacy and safety of available PARPi. The gene discussed is ATM; the disease is prostate carcinoma.