Radiological and clinical features of peripheral keratocystic odontogenic tumor

Peripheral Keratocystic odontogenic tumor (PKCOT) is rare and has not been reported with imaging findings.

The aim of this study was to explore CT and MR imaging characteristics of two PKCOTs in lateral facial deep region (LFDR), and to present a review of the literature regarding their anatomic locations and characteristics of epidemiology and Radiology.

Eighteen PKCOTs, sixteen from the previous literatures and two new cases of the authors, were reviewed. Fifteen of them had original sites in the gingival, one in buccal space and two in LFDR. CT imaging features were based on one PKCOT in the buccal space and two in LFDR. MR imaging features on one PKCOT in LFDR, and conventional radiographic characteristics on eight PKCOTs were analyzed.

The subjects' ages ranged from 37 to 81 years, with a mean of 54.7 years. The male and female ratio was 1:1.14, with no predilection for either gender. Buccal space (6%) and LFDR (11%) were relatively rare original sites to PKCOTs, compared to gingival (83%). PKCOTs were clearly depicted on CT and MR imaging as they had cystic changes. Contents of the cysts were further analyzed by using different series of MRI. No radiological features were found on radiographs except one subject with minimal bone resorption in the alveolar crest.

LFDR is rare original site for PKCOT. PKCOT should be included as one of differential diagnosis of a cystic lesion found in LFDR on CT and MR imaging.