METHODS: We herein presented two patients with PIOC, NOS with different clinical and histopathological features and analyzed gene mutations in these patients using next-generation sequencing (NGS). The typical PIOC, NOS case had many histopathological similarities to oral squamous cell carcinoma (OSCC), including the missense point mutations of TP53 Glu285Val, KDR Gln472His, and APC Pro1433Leu, which are similar to those in other cancers; however, no mutations were detected in the other patient with an atypical presentation of PIOC, NOS, which was derived from a precursor cystic lesion with similarities to both ameloblastic carcinoma and OSCC.
CONCLUSIONS: Genetic analysis suggested that these two PIOC, NOS cases have different features and can be subcategorized.