Microsurgical Trapping, Flow Diversion and Early Chemotherapy for a Ruptured Neoplastic Middle Cerebral Artery Aneurysm Secondary to Choriocarcinoma.

[BACKGROUND AND IMPORTANCE] Ruptured neoplastic cerebral aneurysms (NCAs) due to choriocarcinoma are rare. They are found most commonly in distal middle cerebral artery (MCA) and carry a high risk of rerupture, morbidity and mortality. We present a case of choriocarcinoma-associated NCA managed by a combination of microsurgical-trapping, flow diversion, and low-dose induction chemotherapy initiated in the early postoperative period.

[CLINICAL PRESENTATION] This 3-month postpartum young woman developed subarachnoid hemorrhage in the left sylvian fissure due to an irregular left MCA trifurcation fusosaccular aneurysm. Serum and cerebrospinal fluid beta human chorionic gonadotrophin (β-hCG) levels were elevated. While undergoing a systemic workup, she reruptured and was taken for emergent craniectomy, with microsurgical trapping and excisional biopsy of the ruptured vessel segment. Rest of the unruptured diseased segment in inferior MCA trunk was flow diverted 5 days later using a Pipeline Vantage device (Medtronic) designed for smaller and more distal vessels. In an attempt to halt disease progression and prevent rerupture, 2 low-dose induction chemotherapy cycles (etoposide and cisplatin) were administered immediately over the following 2 weeks. She was later transitioned to etoposide, methotrexate, actinomycin-D + cyclophosphamide, vincristine chemotherapy. She gradually improved and serum β-hCG levels normalized over 4 weeks after surgery. At 6-month follow-up, she had slight disability (modified Rankin Scale 2), and angiogram revealed resolution of inferior MCA aneurysmal dilatation.

[CONCLUSION] This case highlights a strategic synergistic application of microsurgical and endovascular modalities with chemotherapy while balancing the risks of aneurysm rerupture, stent thrombosis, and intracranial hemorrhage. It is also the first reported case of a ruptured NCA treated with flow diversion.