Two cases of odontogenic carcinoma with sclerosing features in the mandible: Diagnostic difficulties in a sclerosing odontogenic carcinoma

Sclerosing odontogenic carcinoma (SOC) is a rare tumor, recently added to current WHO classification. We report two cases of peculiar odontogenic carcinoma consisting of various features including SOC, clear cell odontogenic carcinoma (CCOC), ameloblastic carcinoma (AC), odontogenic fibroma (OF), and fibrous dysplasia-like osteosclerosis. Both cases showed no rearrangements of EWSR1 in break-apart fluorescence in situ hybridization and no V600E mutation of BRAF. We diagnosed both tumors as SOC. SOC may be a distinct odontogenic lesion that has various histological characteristics other than sclerosing features.