Cartilaginous choristoma of the oral cavity: a report of two cases. A choristoma is a tumour-like mass of normal cells in an abnormal location. Intra-oral choristomas are rare lesions. We report on two cases of cartilaginous choristoma, one in the tongue, the most frequently involved oral structure, and another in the upper oral vestibule. We discuss the lesion’s clinical features and their differential diagnosis. The widely accepted metaplastic, embryonal and tumoral histopathologenetic theories are discussed. Surgical excision is the treatment of choice, and no recurrence has been reported.