Rare and massive odontogenic parakeratotic cyst treated by endoscopic sinus surgery: a case report

INTRODUCTION Keratocystic odontogenic tumors are benign neoplasms of odontogenic origin with a potential for aggressive and infiltrative behavior. Many different treatments for this type of lesion have been reported. However, no common consensus has emerged to date regarding the most effective therapeutic approach. Cases of maxillary sinus giant keratocystic odontogenic tumors completely excised by enucleation or marsupialization via endoscopic sinus surgery are extremely rare, and, to the best of our knowledge, only one case has been described in the literature since 2005. CASE PRESENTATION We report a case of a 24-year-old Italian man who came to our department with maxillary sinus region swelling, pain and left nasal obstruction. A massive keratocystic odontogenic tumor involving the right maxillary sinus and causing focal erosions of the bony walls was diagnosed. The keratocystic odontogenic tumor was removed as much as possible by a transnasal approach using endoscopic sinus surgery, which produced optimal surgical and prognostic outcomes. Follow-up is reported for an 8-year period. CONCLUSION Conservative management in this case demonstrated good therapeutic efficacy with a low risk of recurrence. For injuries involving the maxillary sinus, the possibility of decompression or marsupialization by endoscopic sinus surgery should always be considered because it demonstrated the potential to lead to excellent results even after 8 years of follow-up in our patient. To our knowledge, no case report has described follow-up longer than 8 years for a maxillary sinus keratocystic odontogenic tumor treated with endoscopic sinus surgery.