2001 CTOS Annual Meeting Posters— Surgery

THE INFLUENCE OF ANATOMICAL LOCATION ON OUTCOME IN EXTREMITY SOFT TISSUE SARCOMA
C H Gerrand⁴,  R S Bell²,  J S Wunder¹,  R A Kandel¹,  B O'Sullivan²,  C N Catton²,  A M Griffin¹,  A M Davis^3
1University Musculoskeletal Oncology Unit, Mount Sinai Hospital and the University of Toronto,  ²Princess Margaret Hospital of the University Health Network,  ³Toronto Rehabilitation Institute and University of Toronto,  ⁴North of England Bone and Soft Tissue Tumour Service, Freeman Hospital

METHODS: Prospectively collected data relating to patients who underwent limb-sparing surgery for extremity soft tissue sarcoma between January 1986 and April 1997 were analysed. The local recurrence-free and metastasis-free rates were calculated using the method of Kaplan and Meier. Univariate and multivariate analyses of potential predictive factors were evaluated with the log-rank test and the Cox proportional hazards model.

RESULTS: Of 480 eligible patients, 48 (10.0%) had a local recurrence and 131 (27.3%) developed metastases. The median follow-up of survivors was 4.8 years (0.1 to 12.9). There were 139 upper and 341 lower extremity tumors. Upper extremity tumors were more often treated by unplanned excision before referral than lower extremity sarcomas (89 (64.0%) vs 160 (46.9%), p=0.001) and were smaller (6.0cm vs 9.3cm, p=0.000). Lower extremity tumors were more often deep to or involving the investing fascia (280 (82.9%) vs 97 (69.8%), p=0.003). The distribution of histological types differed in each extremity. Fewer upper extremity tumors were treated with adjuvant radiotherapy (98 (70.5%) vs 289 (84.8%), p=0.000). The local recurrence-free rate at five years was 82% in the upper and 93% in the lower extremity (p=0.002). Local recurrence in the Cox model was predicted by surgical margin status (hazard ratio 3.16, p=0.000) but not extremity (p=0.127) or unplanned excision before referral (p=0.868). The metastasis-free rate at five years was 82% in the upper and 69% in the lower extremity (p=0.013). Metastasis was predicted by high histological grade (hazard ratio 17.28, p=0.000), tumor size in cm (hazard ratio 1.05, p=0.001) and deep location (hazard ratio 1.93, p=0.028) but not by extremity (p=0.211).

CONCLUSION: Local recurrence is more frequent after treatment for upper compared with lower extremity sarcomas. Variation in the use of radiotherapy and differences in histological type may be contributory. Metastasis is more frequent after treatment for lower extremity sarcomas because tumors tend to be large and deep compared with upper extremity tumors.