title: Low-grade malignant Triton tumor of the oral cavity: a case report.
abstract: Malignant Triton tumor (MTT) is a malignant peripheral nerve sheath tumor showing rhabdomyoblastic differentiation. It is considered a high-grade neoplasm with poor outcome. This report describes an MTT appearing in the oral cavity. On histologic examination the encapsulated lesion was composed of interlacing fascicles of spindle cells and scattered, large, strap-like pleomorphic cells with abundant eosinophilic cytoplasm. No cross striations were seen. Examination of levels through the tissue showed a total of only 4 normal mitoses and no necrosis. Immunohistochemistry demonstrated diffuse S100 positivity in the spindle cells. The large pleomorphic cells were weakly positive for alpha-sarcomeric actin and myoglobin, although variably but strongly positive for desmin. Management involved a small en bloc resection of the maxilla. After 33 months there was no sign of recurrence or distant metastasis. It was concluded that low-grade variants of MTT occur that do not have an aggressive clinical course.
authors.affiliation: University Dental Hospital of Manchester, Manchester, United Kingdom. jamesj@fsl.den.man.ac.uk
authors.forename: Jacqueline A
authors.initials: JA
authors.lastname: James
authors.forename: Navjit S
authors.initials: NS
authors.lastname: Bali
authors.forename: Philip
authors.initials: P
authors.lastname: Sloan
authors.forename: Jonathan H
authors.initials: JH
authors.lastname: Shanks
mesh_terms: D000199:Actins / Q000032:analysis; D000328:Adult; D003593:Cytoplasm / Q000648:ultrastructure; D003893:Desmin / Q000032:analysis; D003937:Diagnosis, Differential; D005260:Female; D005887:Gingival Neoplasms / Q000473:pathology*; D006801:Humans; D008938:Mitosis; D009211:Myoglobin / Q000032:analysis; D009442:Neurilemmoma / Q000473:pathology*; D009418:S100 Proteins / Q000032:analysis
chemical_list: D000199:Actins; D003893:Desmin; D009211:Myoglobin; D009418:S100 Proteins