Results of radical radiation for chondrosarcoma of bone.

A retrospective analysis has been made of 38 radically treated patients with chondrosarcoma of bone treated with irradiation alone or with concurrent chemotherapy (nine patients) at the Princess Margaret Hospital (P.M.H.) between 1958 and 1981. This includes updated data on previously reported patients. No patient had complete surgery. Tumours in axial sites (25/38 patients) and presenting with pain (25/38 patients) predominate; both well known poor prognostic factors. There is also a greater proportion with unfavourable histology (mesenchymal, poorly differentiated, dedifferentiated) (13/38 patients) compared to other series. The 5 and 10 year actuarial survival rate was 41% and 36% respectively with a median survival of 46 months. The best results were obtained in the group with favourable histology (well and moderately differentiated) with 48% 5 year actuarial survival versus 22% in the unfavourable subgroup. The progression-free survival of the favourable group was 13/25 patients versus 2/13 for the unfavourable group (p less than 0.01). Distant metastasis were rare in the patients with favourable histology (1/24) compared to 5/13 of the unfavourable group. Nine patients were given concurrent chemotherapy and irradiation. To date, only 1/7 patients with favourable histology and combined treatment have had progressive disease (follow-up 8-83 months). Only two patients with unfavourable histology received combined chemotherapy and irradiation and both have relapsed. In conclusion, there is evidence to suggest chondrosarcoma is not radioresistant and irradiation should be considered when surgery would cause major unacceptable morbidity or be technically impossible. Early evidence suggests there may be a role for chemotherapy to supplement the effects of irradiation.