title: Malignant peripheral nerve sheath tumor of the lower labial mucosa: case report and literature review.
abstract: Malignant peripheral nerve sheath tumor (MPNST) is an uncommon soft tissue sarcoma with a predilection for the extremities and trunk of adults, rarely occurring in the oral cavity. To date, 10 cases of MPNSTs affecting the lower labial mucosa have been reported in the English language literature. We describe an additional case of MPNST in the lower labial mucosa of a 67-year-old male patient, who exhibited a painful swelling with a history of 4 months of evolution. Microscopic examination showed dense plexiform fascicles of spindle cells with wavy atypical nuclei. Mitotic figures and nuclear pleomorphism were evident. Immunohistochemical analysis of tumor cells revealed positivity for S-100 protein, CD56, CD34, and neuron-specific enolase but was negative for neurofilament protein, glut-1, claudin-1, desmin, and smooth muscle actin. Ki-67 labeling was 20%. The final diagnosis was MPNST. The lesion was surgically removed with wide margins, with no signs of recurrence after 4 years of follow-up.
authors: Department of Oral Diagnosis and Pathology, Federal University of Rio de Janeiro School of Dentistry (UFRJ), Rio de Janeiro, Brazil.
authors: Thiago Lucena
authors: TL
authors: do Amaral
authors: University of Planalto Catarinense School of Dentistry, Lages, Santa Catarina, Brazil.
authors: Renato
authors: R
authors: Valiati
authors: Department of Oral Diagnosis and Pathology, Federal University of Rio de Janeiro School of Dentistry (UFRJ), Rio de Janeiro, Brazil.
authors: Bruno Augusto Benevenuto
authors: BA
authors: de Andrade
authors: Department of Oral Diagnosis, State University of Campinas, Piracicaba Dental School (FOP-UNICAMP), São Paulo, Brazil.
authors: Alicia
authors: A
authors: Rumayor Piña
authors: Department of Oral Diagnosis and Pathology, Federal University of Rio de Janeiro School of Dentistry (UFRJ), Rio de Janeiro, Brazil.
authors: Sandra Regina
authors: SR
authors: Torres
authors: Department of Oral Diagnosis and Pathology, Federal University of Rio de Janeiro School of Dentistry (UFRJ), Rio de Janeiro, Brazil. Electronic address: Marioromanach@ufrj.br.
authors: Mário José
authors: MJ
authors: Romañach
authors: Department of Oral Diagnosis and Pathology, Federal University of Rio de Janeiro School of Dentistry (UFRJ), Rio de Janeiro, Brazil.
authors: Michelle
authors: M
authors: Agostini
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D003937:Diagnosis, Differential; D006801:Humans; D007150:Immunohistochemistry; D008046:Lip / Q000294:innervation*; D008048:Lip Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008297:Male; D018317:Nerve Sheath Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery
chemical_list: D014408:Biomarkers, Tumor