Abstract
Keratocystic odontogenic tumor (KCOT) is a benign uni- or multicystic, intraosseous tumor of odontogenic origin. KCOT is lined with parakeratinized stratified squamous epithelium. Multiple KCOTs are known as one of the stigmata of the inherited nevoid basal cell carcinoma syndrome (NBCCS). The most important clinical features of KCOT are its potential for locally aggressive and infiltrative behavior and its tendency to recur.
In this retrospective study, we examined 90 KCOTs in 68 patients (39 males, 29 females) treated at the Department of Oral and Maxillofacial Surgery, University Hospital of Dentistry, Tokyo Medical and Dental University from 2001 to 2010. Of the 68 patients, 8 (3 males, 5 females) were NBCCS patients and had 30 KCOTs.
Recurrence was found in 24 of 90 tumors (26.7%). Tumors that were marsupialized before enucleation had a lower recurrence rate (16.1%) than those that were not marsupialized before enucleation (34.5%). Tumors with radical treatment of neighboring teeth when enucleating had a lower recurrence rate (3.4%) than those with conservative treatment (37.7%).
Recurrences were mainly found in the area associated with tooth roots that were not removed during the surgical treatment. This was thought to be due to difficult access and thus incomplete removal of all tumor tissue.
The period between primary enucleation and recurrence ranged from 6 months to 5 years, and the majority of recurrences developed within 3 years after enucleation. So, long-term follow-up at regular intervals for at least 3 years after surgery is recommended.
