[A case of chondroblastoma originating from the right 6th rib].

Chondroblastomas are rare neoplasms, and comprise 0.5-1% of histologically proved primary bone tumors. We report a case of the tumor originating form the right 6th rib. The patient, a 15-year-old female, was admitted because the abnormal shadow was found on routine chest X-ray film. It was suspected to be the posterior mediastinal tumor based on the chest X-ray, CT and MRI. In surgery, the tumor was 4.0 x 4.0 x 2.5 cm in size and fixed on the rib, but not invasive to other tissue. The content was rough and soft granuloma like. Histological examination confirmed the diagnosis of chondroblastoma of the rib. The patient is doing well without symptoms of recurrence fifteen months after surgery.