Malignant Peripheral Nerve Sheath Tumor of the Parotid Gland.

ABSTRACT

Malignant peripheral nerve sheath tumor (MPNST) refers to spindle cell sarcomas arising from or separating in the direction of cells of peripheral nerve sheath. The MPNST of the parotid gland is an extremely rare tumor, accounts for < 5% of all soft tissue sarcomas, and carries a poor prognosis. In this article, we report a case of MPNST of parotid gland in a 45-year-old male and review its diagnostic and therapeutic challenges. A 45-year-old male presented with right parotid swelling for 2 years with rapid increase in size over the last 3 months. He underwent right total conservative parotidectomy with selective neck dissection. Reconstruction was done with microvascular anterolateral thigh flap. On immunohistochemistry, the tumor cells expressed CD 56 diffusely and S 100 focally. Tumor was immunonegative for CK, Desmin, SOX - 10, and SMA consistent with MPNST. The MPNSTs arising as parotid mass are very rare and aggressive tumors. The role of IHC is paramount in establishing the diagnosis. Multimodal management including wide surgical resection, neck dissection, and adjuvant chemoradiotherapy is the choice of treatment.