COMPARISON OF OUTCOMES OF SOFT TISSUE SARCOMA ARISING IN THE POPLITEAL FOSSA OR POSTERIOR THIGH

Abstract

Many authors believe that size, histological grade and depth are the best predictors of outcome in soft tissue sarcoma. Enneking’s surgical staging system included compartmental status, and was intended to guide surgical intervention as well as provide prognostic information. Advances in surgical and radiotherapy techniques may mean that extracompartmental status is no longer a poor prognostic factor. We compared a group of popliteal fossa sarcomas with a group from the posterior thigh, and found that although the former group required more extensive surgery to obtain wide margins, their functional and survival outcomes were similar.

No single staging system has been generally accepted for extremity soft tissue sarcoma, although histologic grade, size and depth are widely accepted as prognostic indicators. Enneking outlined a surgical staging system which used compartmental status as a predictor of outcome. However, surgical reconstruction and adjuvant radiotherapy have advanced considerably. We wanted to know if a tumour arising in the popliteal fossa still had poorer survival or functional outcome in the light of these advances.

We identified twenty-three patients who had sarcomas of the popliteal fossa and forty-six patients who had sarcomas of the nearby posterior thigh compartment. Popliteal sarcomas were not of a different size or more likely to present with metastasis. Popliteal tumours more frequently required reconstructive techniques such as local or free tissue transfer and skin grafting than posterior thigh tumours (39.1% v 4.3% respectively). Popliteal tumours were also more likely to undergo a dissection or reconstruction of the major neurovascular structures of the lower limb (30.4% v 0% respectively). There was no difference in local or systemic recurrence rates between the groups. TESS and MSTS 1987 functional scores also showed no difference between the groups.

We conclude that popliteal fossa sarcomas require a greater level of surgical intervention to follow sound principles of sarcoma resection and achieve reconstruction of the ensuing soft tissue defect. However, if these principles are followed in a planned multidisciplinary setting, then survival and functional results similar to the posterior thigh can be expected.