CHONDROSARCOMA OF THE PELVIS - PROGNOSTIC FACTORS FOR 67 PATIENTS TREATED WITH DEFINITIVE SURGERY

BACKGROUND. Chondrosarcoma (CS) most commonly involves the pelvis. Loc al and systemic failures often result in poor outcome. Prognostic fact ors that determine patient outcome remain ill-defined. METHODS. We ret rospectively analyzed 67 patients with CS of the pelvis treated by def initive surgery from January 1970 to December 1992. All patients had l ocalized disease including Grade 1 (19 patients), Grade 2 (18 patients ), Grade 3 (17 patients), and dedifferentiated (13 patients) tumors. T hirty-two patients underwent a limb-sparing surgical resection and 35 patients underwent hemipelvectomy. Follow-up was available for all pat ients. The median duration of follow-up for the survivors was 115 mont hs (range, 24-288 months). RESULTS. At last follow-up, 52% of the pati ents were disease free, 8% were alive with disease, 36% died of diseas e, and 4% died of other causes. Nineteen patients (28%) had developed a local recurrence (LR). The median time to LR was 23 months (range, 1 -111 months). Independent variables in a multivariate analysis associa ted with increased risk of LR included inadequate surgical margin, tum or epicenter in the pubis, and high grade histology. LR did not influe nce overall patient survival. Twenty-three patients (36%) developed di stant metastases at a median time of 9 months (range, 1-111 months) po stoperatively. Metastases developed in 0% of the patients with Grade 1 , 20% of the patients with Grade 2 60% of the patients with Grade 3 an d 75% of patients with dedifferentiated CS. On multivariate analysis, histologic high grade was the only significant predictive variable for distant relapse (P = 0.005). CONCLUSIONS. The critical issue for a fa vorable outcome in low grade CS of the pelvis is adequate surgical exc ision (i.e., negative surgical margin). The high rate of systemic fail ure in high grade and dedifferentiated CS, despite adequate surgery, e mphasizes the need for more effective systemic therapy. (C) 1996 Ameri can Cancer Society.