OSSEOUS CHORISTOMA OCCURRING AT THE BASE OF THE TONGUE

Abstract

　Osteomas usually occur contiguous to bone tissues, such as in the hard palate, submandibular bone, or nasal-paranasal cavity, in the head and neck legion. We encountered a case of osseous choristoma occurring at the base of the tongue, with no contiguity to any bone tissue. The patient was a 52-years-old woman who presented with the chief complaint of pharyngeal discomfort. Although a tumor-like lesion of the oral cavity was pointed out to her by her family doctor, she did not pursue further testing, as she was asymptomatic. The tumor, which was located at the root of the tongue, with a little blood vessel running on its surface, was smooth. However it was very hard, with a white surface, and immobile. Total resection under general anesthesia was performed. It was very easy to resect the tumor because of the clear boundary between the tumor capsule and the deeper tissue of the tongue. The resected tumor measured 10×7×5 mm in size, and no steal or in-out flow vessels were found. No atypical changes of the mucous membrane were found and the layer structure of the trabeculae in the tumor, as in bone tissue, was remarkable. Based on the findings, the tumor was diagnosed as an osseous choristoma. There has been no recurrence of the tumor as at the time of writing.