Four-year complete remission with reduced-dose PARP inhibitor in advanced-stage epithelial ovarian cancer harboring a BRCA1 mutation: a case report of a chemotherapy-intolerant patient with idiopathic thrombocytopenic purpura.

BACKGROUND: Ovarian cancer is a type of gynecological malignant tumor with high mortality rate, for which the standard primary treatment consists of cytoreductive surgery followed by platinum-based chemotherapy. However, a common adverse effect of carboplatin-paclitaxel regimen is thrombocytopenia due to bone marrow suppression. For ovarian cancer patients with preexisting idiopathic thrombocytopenic purpura (ITP), there exists a dilemma of balancing oncologic efficacy and hematologic safety. As a targeted therapy, poly ADP-ribose polymerase (PARP) inhibitor is more tolerable to platelet toxicity.

CASE PRESENTATION: This report presents a 55-year-old woman with a 20-year history of ITP who was diagnosed with high-grade serous ovarian carcinoma (FIGO stage IIIC). Due to persistent thrombocytopenia, she was unable to tolerate postoperative carboplatin-paclitaxel chemotherapy. Molecular profiling revealed a breast cancer gene 1 (BRCA1) mutation, prompting initiation of olaparib alongside ITP-directed therapy. Over four years of follow-up, the patient achieved sustained tumor remission with stable platelet counts.

CONCLUSIONS: This case underscores the potential role of PARP inhibitors as a safe and effective alternative for ovarian cancer patients with concurrent ITP, maintaining both favorable oncologic result and hematologic stability.