Although mutational signature 3 and therefore HR proficiency predicted efficacy of this combination therapy, therefore implying an application for niraparib and pembrolizumab in BRCA-deficient tumors, it was also encouraging that PD-L1 presence and interferon priming of immune cells present in the tumor microenvironment can be used to estimate responsiveness to the combination therapy independent of HRD. Here, CD274 is linked to neoplasm.