Primary intraosseous squamous cell carcinoma arising from keratocystic odontogenic tumor: CK 17 evaluation

Primary intraosseous squamous cell carcinoma (PIOSCC) derived from an odontogenic keratocyst (OKC) is a rare malignant neoplasm of the jaws, which is locally aggressive, with predominantly poor prognosis. The number of well-documented cases of PIOSCC ex OKC is extremely small; thus sufficient incidence data are not available in the literature. Overall and disease-free survival is poor, with almost 50% patients failing to survive within the first 2 years of follow-up, and this can be attributed to the delayed diagnosis. Knowledge of the clinical, radiographic, and histopathologic features of primary intraosseous squamous cell carcinoma (PIOSCC) allows accurate diagnosis and appropriate treatment of this rare malignancy.