Solid tumors rarely present with leptomeningeal carcinomatosis (LMC) without systemic disease.

Rare case of diffuse LMC as the initial presentation of advanced pancreatic adenocarcinoma is reported.

TB meningitis with no neoplastic signs and negative cerebrospinal fluid (CSF) cytology can mimic LMC.

Multiple CSF samples may be required to identify malignant cells and direct treatment.