Improving our Understanding of the Management and Pathogenesis of Rare and Neglected Tumors of the Central and Peripheral Nervous System Frontiers Research Topic Pathology Outlines Malignant peripheral nerve sheath tumor (MPNST) Pathology Outlines Malignant melanotic nerve sheath tumor Leiomyosarcoma of Scalp Skin Cancer and Reconstructive Surgery Center Clear cell sarcoma in unusual sites mimicking metastatic melanoma