Psammomatous melanotic schwannoma a rare neck lump The Annals of The Royal College of Surgeons of England Frontiers Sporadic spinal psammomatous malignant melanotic nerve sheath tumor: A case report and literature review Malignant melanotic nerve sheath tumor with PRKAR1A, KMT2C and GNAQ mutations Non psammomatous melanocytic schwannoma presenting as a subcutaneous nodule: A rare presentation of a rare lesion