Leptomeningeal carcinomatosis following neoplastic cerebral aneurysm rupture: a case report.

BACKGROUND: Several possible mechanisms exist for the spread of a primary tumor to the leptomeninges in leptomeningeal carcinomatosis. This report describes a case caused by direct bleeding in the subarachnoid space from a neoplastic cerebral aneurysm rupture.

CASE DESCRIPTION: A 48-year-old Japanese woman, who was diagnosed with breast carcinoma (pT3 pN2 M0) at the age of 45 years and underwent mastectomy and chemotherapy, was admitted in a coma following a sudden-onset severe headache. Computed tomography revealed diffuse hemorrhage in the subarachnoid space and angiography revealed an aneurysm at the distal middle cerebral artery (MCA). Superficial temporal artery-MCA bypass, aneurysmal trapping, and aneurysm resection were performed within 24 h of admission. Staining for AE1/AE3 revealed accumulation of atypical cells with a high nuclear-cytoplasmic ratio in the aneurysmal wall. After showing initial improvement, she developed disturbed consciousness due to complicated ventricular enlargement on day 45. Although the cerebrospinal fluid in the acute phase had no atypical cells, subsequent testing revealed atypical cells, which supported a diagnosis of leptomeningeal carcinomatosis due to breast cancer dissemination. The patient died on day 78 after receiving standard endocrine therapy and radiation therapy.

CONCLUSIONS: Tumor cells reach the leptomeninges via hematogenous spread or direct extension from preexisting lesions, and can undergo neuraxis dissemination via the cerebrospinal fluid. Subarachnoid hemorrhage and leptomeningeal carcinomatosis are both devastating conditions with extremely poor prognoses. This patient experienced delayed disturbed consciousness leptomeningeal carcinomatosis with decreased performance status, which made it difficult to justify aggressive treatment based on her poor prognosis.