Recurrence and malignant transformation of endotracheal chondroma.

An endotracheal chondroma with recurrent course and malignant transformation is described. The first chondroma recurrence appeared 5 years after the primary operation, with no histopathological signs of malignancy. A second recurrence after a further 6 years showed obvious histological evidence of malignant chondrosarcoma. A third recurrence after 1 more year metastasized to various organs and led to the patient's death 14 years from the date of primary diagnosis.