Diplopia in a patient with carcinomatous meningitis: A case report and review of the literature

In a patient with a history of malignancy, an isolated neurologic sign or symptom may indicate metastasis to the central nervous system. To exclude this possibility, a lumbar puncture should still be performed after a nondiagnostic cranial computed tomography (CT) scan even in the absence of signs of infection. A case is presented of a 59 year-old man recently diagnosed with non-Hodgkin's lymphoma that presented to the Emergency Department (ED) with the sole complaint of diplopia. Examination was unremarkable except for a left abducens nerve palsy. Cranial CT scan was normal but initial cerebrospinal fluid results were suggestive of carcinomatous meningitis, and cytology results later confirmed this diagnosis. A review of diplopia and carcinomatous meningitis is presented, along with a suggested conservative diagnostic algorithm for cancer patients presenting with neurologic signs or symptoms.