Malignant peripheral nerve sheath tumor of facial nerve: Presenting as parotid mass

Abstract

Malignant peripheral nerve sheath tumor (MPNST) is very uncommon tumor of parotid gland and it is an uncommon spindle cell sarcoma accounting for approximately 5% of all soft-tissue sarcoma. There is strong association between MPNSTs and neurofibromatosis (NF-1) and previous irradiation. Structural abnormality of chromosome 17 is associated with NF-1 and so MPNST. We present a case of a 78-year-old male presenting with slowly growing parotid mass who underwent tumor resection.

Malignant Peripheral Nerve Sheath Tumors of the Head and Neck: A Case Series and Literature Review

“…MPNSTs are very rare tumors with incidents of approximately 0.001% in the population [ 3 , 9 ]. These tumors usually affect the proximal extremities and trunk and are very rare in the head and neck [ 6 , 10 – 12 ]. They usually arise in adulthood, with most occurring around 20–50 years of age [ 13 ].…”

“…Similar to most soft-tissue sarcomas, surgery is the primary modality used to treat MPNSTs of the head and neck, with complete surgical excision of the tumor with negative margins correlating with longer overall survival [ 2 , 6 , 7 , 18 – 21 ]. However, given the relatively small space within the head and neck, the proximity to vital structures, and the potential for microscopic local spread, obtaining negative margins can be difficult.…”

Peripheral nerve sheath tumors arising in salivary glands: A clinicopathologic study

“…found that 35% (n=62) of their patients with MPNST had a history of Neurofibromatosis I [20], neither our nor the 9 prior cases of MPSNT arising from the parotid gland have indicated a history of this genetic condition [3][4][5][6][7][8][9][10][11].…”

“…Surgical resection usually yields excellent results in the management of these lesions [13,22,24] MPNST arising from the parotid gland have presented as both tender [6,7,[9][10][11] and non-tender [3][4][5]8] masses which have grown slowly over the course of 3-12 months, but can progress in a more accelerated time frame [6]. Of the 9 cases within the literature, only one has shown facial nerve palsy at the time of presentation [6].…”

“…A single institution retrospective analysis by Cho et al found that neurofibromas and schwannoma comprised 0.2% (n=1) and 1.1% (n=6) respectively of 527 mesenchymal tumors found in salivary glands [1]. Of the 22 neurofibromas [2], 9 [3][4][5][6][7][8][9][10][11] MPSNT, and approximately 150 schwannomas [12][13][14][15][16][17][18][19][20][21][22] in the literature that have been found to arise in the salivary gland, the vast majority have been reported as single case reports or small series [13].…”