[Multiple cartilaginous exostoses and neoplastic degeneration: review of the literature (author's transl)].

In about 10% of patients suffering from multiple osteochondroma a malignant degeneration of one osteochondroma occurs. Data of 59 patients are collected from the literature. The malignant degeneration occurs at the age of 31 in average, mostly on the pelvic girdle, less frequently on the shoulder girdle and on the ribs. The development is slow in most cases, at times interrupted. The first clinical signs are an increase in swelling, rarely pain or neurological symptoms. Radiological findings and prognosis correspond well with those of a proliferative chondroma or a primary chondrosarcoma. Recurrences after local treatment are frequent, metastases are rarely found. Regular check-ups and good information of patients suffering from multiple osteochondroma are recommended.