Leptomeningeal Disease Secondary to Invasive Ductal Carcinoma of the Breast: A Rapidly Progressive and Fatal Complication.

Leptomeningeal disease (LMD) is a rare yet serious complication of advanced malignancy, often seen in breast cancer and associated with a poor prognosis.  This case report highlights the rapid progression and diagnostic challenges encountered in a woman in her 40s with advanced breast cancer who presented with severe headaches, absence seizures, and diplopia. The patient's complex past history included invasive ductal carcinoma, prior brain metastasis, and recent craniotomy, which added significant challenges to diagnosis and management.  Clinical investigations included computed tomography (CT) of the head, magnetic resonance imaging (MRI) of the orbit and head, electroencephalography (EEG), and lumbar puncture, which indicated optic nerve sheath enhancement, ventricular prominence, coating of facial and vestibulocochlear nerves, and cerebrospinal fluid abnormalities suggestive of LMD. Although empiric treatment for bacterial and tuberculous meningitis was initiated, the patient's rapid decline necessitated an aggressive multimodal approach. Management included high-dose corticosteroids, broad-spectrum antibiotics, antitubercular drugs, and anticonvulsants, though her seizures persisted. Ultimately, comfort-focused care was prioritized as her condition remained refractory to interventions, and she was transitioned to palliative care.  This case emphasizes the need for early suspicion, prompt multidisciplinary involvement, and the challenges in managing complex oncological cases with atypical neurological manifestations. The poor prognosis associated with LMD reflects the limitations of current therapeutic strategies and the need for a nuanced approach to care.