Carcinomatous meningitis mimicking Creutzfeldt-Jakob disease.

We report a case of carcinomatous meningitis diagnosed at autopsy that was clinically diagnosed as a case of Creutzfeldt-Jakob disease (CJD) because of rapidly evolving dementia. Pathological study revealed diffusely spreading carcinomatous meningitis, infiltrating into cortex along Virchow Robin space. Immunostaining for Prion protein was negative. Despite advances in clinical diagnosis, tissue diagnosis remains a pre-requisite for confirmation of CJD.