A para aortic malignant melanotic nerve sheath tumor mimicking a gastrointestinal stromal tumor: a rare case report and review of literature BMC Surgery Springer Nature Link Spotty skin pigmentation and multiple blue naevi as cutaneous markers for spinal melanotic schwannoma BMJ Case Reports Pathology Outlines Malignant melanotic nerve sheath tumor Psammomatous melanotic schwannoma a rare neck lump The Annals of The Royal College of Surgeons of England View of Malignant melanotic nerve sheath tumor with PRKAR1A, KMT2C and GNAQ mutations Free Neuropathology