Malignant melanotic nerve sheath tumour of chest wall: a rare and diagnostically challenging case
DOI:
https://doi.org/10.18203/2320-6012.ijrms20243404Keywords:
Melanotic, Nerve sheath tumour, BRAFV600EAbstract
Malignant melanotic nerve sheath tumour (MMNST), previously known as melanotic schwannomas (MS) comprise less than 1% of nerve sheath tumors and around 200 cases have been reported in the literature. According to the WHO 5th edition, it is now classified as malignant neoplasm due to its local recurrence rate and metastatic risk. Although it is classified as malignant, the histopathological criteria for malignancy and prognostic factors remain ill-defined due to its rarity. It also poses a diagnostic challenge as it resembles closely other benign as well as malignant melanin producing tumors. We report here a case of 33 year old female who presented with chest wall swelling and was diagnosed as MS (now classified as MMNST) on histopathology and immunohistochemistry. This case highlights the diagnostic difficulties and the importance of careful histological evaluation and long-term follow-up.
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