An uncommon granular cell tumor which may metastasize to other anatomic sites. Morphologic characteristics include the presence of spindling neoplastic cells, necrosis, extensive pleomorphism, prominent nucleoli, and increased mitiotic activity. The disease is granular cell cancer (Monarch Disease Ontology id MONDO_0003252). Also known as: granular cell tumor, malignant, granular cell tumor, malignant (morphologic abnormality), malignant granular cell myoblastoma, malignant granular cell neoplasm, malignant granular cell tumor, malignant granular cell tumour, myoblastoma, malignant.