Leptomeningeal Disease and Hydrocephalus as the First Presentation of Melanoma

We present a case of an 83-year-old man who developed acute hydrocephalus as the first presentation of leptomeningeal disease secondary to melanoma of unknown primary, which is an exceedingly rare subtype of melanoma, in addition to a very rare complication of malignancy in general, which was diagnosed with imaging as well as cytology modalities. This presentation is rare and highlights the importance of recognizing this condition.