The patient went on to craniotomy. 

MACROSCOPIC DESCRIPTION: Multiple pieces of rubbery dark brown-red tissue 22x22x4mm in aggregate. A1. 

MICROSCOPIC DESCRIPTION: The section shows fragments of blood clot mixed with fragments of a densely hypercellular tumor. Tumor cells have spindle and epithelioid morphology with marked nuclear and cellular pleomorphism. The cytoplasm of several atypical cells contains finely granular black/ brown pigment. Atypical cells are admixed with large numbers of monocyte-macrophages and CD3+ T lymphocytes. Hemosiderin pigment is present within the cytoplasm of many of the monocyte-macrophages. There are scattered mitotic figures. The atypical cells show strong immunostaining for tyrosinase, melan A, HMB-45 and S-100 protein. The features are of metastatic malignant melanoma.

DIAGNOSIS: Metastatic malignant melanoma.