RAD51D and neoplasm: Because non-BRCA HRR genes function differently within the HRR pathway, niraparib treatment response was also evaluated in patients with tumor mutations in the more well-characterized HRR genes known to contribute to HRD and PARPi sensitivity (i.e., RAD51C, RAD51D, BRIP1, and PALB2) and patients with other, less well-studied HRR genes.