Leptomeningeal Carcinomatosis from Squamous Cell Carcinoma of the Ethmoid Sinus: A Case Report

Leptomeningeal carcinomatosis (LMC) is an end-stage disease with poor prognosis. This disease has not yet been reported with sinonasal carcinomatosis. We present a case of a patient who presented with posterior ethmoid/anterior cranial mass which turned out to be poorly differentiated squamous cell carcinoma (SCC). Later the patient presented with enhancement of the spinal roots and a lumbar puncture diagnosed the leptomeningeal spread of her primary disease. After intrathecal chemotherapy and palliative radiation, the patient failed to resist her disease seven months after the diagnosis. We present the first case report of leptomeningeal spread of sinonasal cancer. Although it seems rare, LMC should be on the differential of patients presenting with neurological deficits.