title: Clinicopathological and immunohistochemical features of oral spindle cell carcinoma.
abstract: BACKGROUND
  Oral spindle cell carcinoma (SpCC) is a rare variant of oral squamous cell carcinoma (SCC). The aims of this study were to compare the clinicopathologic and immunohistochemical features of oral SpCC with conventional oral SCC.
  
  
  METHODS
  Five cases of oral SpCC and 10 cases of oral SCC (five well-differentiated and five poorly differentiated) were evaluated through conventional hematoxylin and eosin staining and immunohistochemical reactions to cytokeratins (CK), vimentin, desmin, smooth muscle actin, muscle-specific actin, S-100 protein, epithelial membrane antigen (EMA), p53, and ki-67.
  
  
  RESULTS
  Oral SpCC showed predilection for males on their sixth decade of life, presenting clinically as painful infiltrative ulcers or ulcerated exophytic polypoid masses, preferably located on the alveolar mucosa. Mesenchymal markers were expressed in the spindle cell but not in the carcinomatous component of SpCC, and it was negative in all SCC. CKs AE1/AE3, 6, 14, and EMA were positive on both carcinomatous and spindle cell components of most SpCCs. These tumors also presented higher p53 and ki-67 expression and no CK 1 expression in contrast to well-differentiated SCC.
  
  
  CONCLUSIONS
  Oral SpCC presented a different clinical profile than conventional SCC and histopathologic features and p53 and ki-67 expression closer to poorly differentiated SCC. Besides mesenchymal markers, CK AE1/AE3, 6, 14, and EMA expression on spindle cells may be useful as an adjunct on microscopical differential diagnosis of SpCC.
authors.affiliation: Oral Pathology, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil.
authors.forename: Mário José
authors.initials: MJ
authors.lastname: Romañach
authors.forename: Rebeca Souza
authors.initials: RS
authors.lastname: Azevedo
authors.forename: Roman
authors.initials: R
authors.lastname: Carlos
authors.forename: Oslei Paes
authors.initials: OP
authors.lastname: de Almeida
authors.forename: Fábio Ramôa
authors.initials: FR
authors.lastname: Pires
mesh_terms: D000199:Actins / Q000032:analysis; D000328:Adult; D000367:Age Factors; D000368:Aged; D002277:Carcinoma / Q000473:pathology*; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D003893:Desmin / Q000032:analysis; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053535:Keratin-13 / Q000032:analysis; D053547:Keratin-14 / Q000032:analysis; D053553:Keratin-6 / Q000032:analysis; D053533:Keratin-8 / Q000032:analysis; D007633:Keratins / Q000032:analysis; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000473:pathology*; D018396:Mucin-1 / Q000032:analysis; D009418:S100 Proteins / Q000032:analysis; D012737:Sex Factors; D016159:Tumor Suppressor Protein p53 / Q000032:analysis; D014746:Vimentin / Q000032:analysis
chemical_list: D000199:Actins; D003893:Desmin; D053535:Keratin-13; D053547:Keratin-14; D053553:Keratin-6; D053533:Keratin-8; D019394:Ki-67 Antigen; D018396:Mucin-1; D009418:S100 Proteins; D016159:Tumor Suppressor Protein p53; D014746:Vimentin; D007633:Keratins