Conclusions

• This data suggests that IDC-P harbors targetable molecular alterations in DDR genes (BRCA1/2 and CDK12) with approved targeted agents (e.g. PARP inhibitors).
• We also found enrichment of oncogenic FOXA1 mutations in IDC-P which are associated with prostate cancer progression, castrate-resistance and an unfavorable prognosis.
• There were no tumors which demonstrated mismatch-repair deficiency (dMMR) or microsatellite instability and none of the profiled tumors had a high tumor mutational burden ( > = 10 mutations/megabase).
• Further efforts are ongoing to expand this cohort of IDC-P cases and compare them with a matched cohort of pure adenocarcinoma cases and will include analysis of key RNA expression signatures.