Osseous choristoma is an extremely rare benign lesion characterized by ectopic bone formation in the soft tissue of the head and neck region. We report two cases of osseous choristoma occurring at the base of the tongue.

Case 1 was a 17-year-old woman who was referred to our hospital with an asymptomatic pedunculate mass in the tongue; she had first noticed the mass approximately eight years prior to her admission. Case 2 was a 68-year-old man referred to our hospital with the complaint of discomfort in the throat. Fiberoptic laryngoscopic examination revealed a pedunculated and smooth mass measuring approximately 10 mm in diameter on the left side of the cecal foramen of the tongue in both cases. We performed transoral surgical excision of the lesion at the clinic, and microscopic examination of the specimen revealed the lesion as being composed of lamellated bone and covered with normal epithelium. The histopathological diagnosis was osseous choristoma in both cases.

In this report, we review 22 cases of osseous choristoma reported in the literature since 2001 and discuss their clinical findings.