Odontogenic carcinosarcoma: morphologic and immunohistochemical description of a case.

Objectives: The goal of this study was to describe an extremely rare case of odontogenic carcinosarcoma and compare the findings with those of a literature review.

Study Design: The clinical and pathologic data of an odontogenic carcinosarcoma affecting the posterior maxilla of a 42-year-old male patient was described. The lesion was immunostained for cell-cycle, cytokeratin, and mesenchymal markers. A review of literature from 1960 to 2017 was conducted in a search for similar well-documented case reports. Descriptive statistics were calculated to compare clinical and pathologic variables.

Results: In the reported case, the percentage of Ki-67-positive epithelial and mesenchymal cells was estimated as 40% and 25%, respectively. Epithelial cells were focally positive for cytokeratin 7, -8, -14, and -18, and diffusely positive for cytokeratin 19, p53, and p16. Mesenchymal cells were strongly positive for desmin, HHF-35, and vimentin. Our review showed that odontogenic carcinosarcoma is diagnosed mostly in the advanced stage. All patients with relapsed tumors had died as a result of the disease.

Conclusions: Very few cases have been reported in the literature supporting that most odontogenic carcinosarcoma develop in the posterior mandible in a wide age range, without gender and racial predilections. Only one case of odontogenic carcinosarcoma in the maxilla other than the one described here has been reported. Until today, the best treatment remains unknown.