A rare case of thymoma in a 15-month-old girl.

We report a case of thymoma in a 15-month-old girl successfully treated with thymectomy. This case is unique due to the very young age of the child and a family history of thymoma in the father, who was treated with resection at age 10. Radiographic and CT findings mimicked thymic hyperplasia, and highlight the difficulty of distinguishing between these two conditions, since the latter is more common in children. The case is followed by a discussion of thymic hyperplasia and thymoma.