Recurrent metastatic malignant peripheral nerve sheath tumor associated with neurofibromatosis I: a rare case with atypical immunohistochemistry Anais Brasileiros de Dermatologia Pathology Outlines Malignant melanotic nerve sheath tumor Improving our Understanding of the Management and Pathogenesis of Rare and Neglected Tumors of the Central and Peripheral Nervous System Frontiers Research Topic Cauda Equina, Paraspinal, and Peripheral Nerve Tumors Neupsy Key Malignant melanotic nerve sheath tumor with PRKAR1A, KMT2C and GNAQ mutations