Plexiform Schwannoma: A Report of Two Unusual Cases, and a Review of the Literature

Shabnum Ali, Leandros Vassiliou, Philip Stenhouse

Department of Oral and Maxillofacial Surgery, Queen Mary’s Hospital, Sidcup, UK.

DOI: 10.4236/ojst.2014.44026                

Abstract

Plexiform schwannoma is a benign tumour arising from the sheath of myelinated nerve fibres that may occur in any part of the body. It is very rare in the head and neck region and poses diagnostic challenges. Here we present two unusual cases. The first is about a fifteen-year-old boy with a large plexiform schwannoma in the right retro maxillary region, extending up to but not invading the orbit. Initial cytology reported it as a pleomorphic adenoma, but histological findings after excision confirmed it to be a benign plexiform schwannoma. A zygomatic osteotomy was required to excise the tumour in its entirety. The second reported case is about solitary lesion on the tongue of a 46-year-old Chinese man, clinically mimicking a mucocoele. This case report highlights the diagnostic challenges posed by plexiform schwannoma, and the role of imaging and cytopathology, as well as the importance of definitive histopathological analysis. It also describes the surgical management of these lesions, and provides a review of the literature, in particular of cases occurring in the head and neck region.

Keywords

Plexiform Schwannoma, Benign Nerve Sheath Tumour

Conflicts of Interest

The authors declare no conflicts of interest.

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