%0 Review
%T Maxillary clear cell odontogenic carcinoma with EWSR1-ATF1 fusion gene mimicking sclerosing odontogenic carcinoma: A case report and literature review.
%A Xie R
%A Wang W
%A Thomas AM
%A Li S
%A Qin H
%J Pathol Res Pract
%V 241
%N 0
%D Jan 2023
%M 36470043
%F 3.309
%R 10.1016/j.prp.2022.154257
%X Both clear cell odontogenic carcinoma (CCOC) and sclerosing odontogenic carcinoma (SOC) are rare odontogenic malignancies. Here, we report a case of maxillary CCOC whose clinical and histologic features resembled those of SOC. Radiologically, the tumor presented as an ill-defined, expansile radiolucency with local bone destruction. Histologically, the tumor was comprised of thin cords or strands of odontogenic epithelium permeating through a sclerosed fibrous stroma with occasional clear cell foci. It damaged the cortical plates and invaded the adjacent soft tissue. Immunohistochemical expression of Pancytokeratin, Cytokeratin 19, p63, Cytokeratin 5/6, and Cytokeratin 14, as well as focal expression of Cytokeratin 7, demonstrated the epithelial nature of the tumor. Alcian Blue Periodic acid Schiff staining revealed a lack of intracellular mucin. Fluorescence in situ hybridization analysis revealed Ewing sarcoma RNA binding protein 1 and activating transcription factor 1 gene translocation, further confirming the diagnosis of CCOC. Lastly, we contextualized the genetic analysis of our case to that of CCOC in the literature.