To date, no data are available about the potential role of Ki67 IHC expression in predicting PARPi response, but several reports showed that OC patients who have a high proliferation index (PI) are more likely to have poor prognostic factors, including an advanced FIGO stage, a higher tumor grade, a bulk residual tumor, and a poor response to chemotherapy, and also have a less favorable 5-year survival compared with those with a low PI [31,32,33]. Here, MKI67 is linked to neoplasm.