SECONDARY CHONDROSARCOMA IN OSTEOCHONDROMAS - MEDULLARY EXTENSION IN 15 OF 45 CASES

We reviewed 45 secondary chondrosarcomas: 16 arising in solitary osteo chondromas and 29 in 27 patients with multiple osteochondromas. Less t han radical or wide primary surgery resulted in local recurrence in 8 of 14 lesions: 2 of 2 intralesional excisions, 5 of 11 marginal excisi ons, and in one case with radiotherapy alone. No local recurrence was found after a primary wide surgical procedure in 30 lesions and a radi cal procedure in 1 lesion after a mean of 8 (0.2-22) years' follow-up. 5 patients had died: 3 of pulmonary metastases (2 stage in, 1 stage I IB), and 2 of local tumor invasion, both in the spine. Medullary invas ion occurred in 15 of 45 lesions, this was oftener than reported in se condary chondrosarcoma. Medullary invasion was not always detected pre operatively, even when MR or CT examinations had been performed. There fore, we recommend that a secondary chondrosarcoma should be removed w ith a wide surgical resection, including a part of the underlying bone , to keep the local recurrence risk low. There were no clinical or pro gnostic differences between tumors that had arisen from solitary or fr om multiple osteochondromas.