This obstacle extends beyond rare cancers: The premature dismissal of olaparib in ovarian cancer and the seven to ten year delay in addressing Programmed Cell Death Ligand 1 (PD-L1) expressing breast and gynecological cancers with PD-L1 inhibition illustrate the need for biomarker-driven stratification for cancer treatment5,6. Here, CD274 is linked to ovarian carcinoma.