EC Dental Science

Malignant melanotic nerve sheath tumour is an exceptionally discerned, aggressive peripheral nerve sheath tumour. Malignant melanotic nerve sheath tumour may emerge as a sporadic neoplasm or configure a segment of Carney complex. Previously designated as a benign neoplasm, tumefaction commonly emerges in concurrence with spinal nerves or visceral autonomic nerves.

As per contemporary classification of World Health Organization (WHO), malignant melanotic nerve sheath tumour is associated with malignant biological behaviour. Neoplasm is consistently comprised of Schwann cells demonstrating melanocytic differentiation and exhibits fascicles or sheet-like proliferation of intensely pigmented, uniform, plump, spindle shaped cells. Tumour cells manifest a co-expression of S100 protein and SOX10 along with immune reactivity to melanocytic markers as human melanoma black 45 (HMB45) antigen or MelanA. Absence of PRKAR1A expression suggests a link to Carney complex.

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6. Image 1 Courtesy: Pathology outlines.
7. Image 2 Courtesy: Hindawi.com.