PATHOLOGICAL FEMORAL FRACTURE AFTER PERIOSTEAL EXCISION AND RADIATIONFOR THE TREATMENT OF SOFT-TISSUE SARCOMA

BACKGROUND. Surgical resection and adjuvant radiation therapy are stan dard therapy for soft tissue sarcomas. When the tumor approximates bon e, periosteal excision may be necessary. It was hypothesized that peri osteal stripping and radiation therapy would increase the rate of path ologic fracture. METHODS. The soft tissue sarcoma data base at the Mem orial Sloan-Kettering Cancer Center was used to identify a consecutive series of 205 patients who were treated over a 15-year period (1982-1 997). All patients had a soft tissue sarcoma of the thigh, which was m anaged by limb-sparing surgery and radiation therapy. Patients who had bone invasion by tumor or bone resection were not included. RESULTS. Nine patients, including eight women and one man, developed a femoral fracture in an area of previous radiation and surgery, All nine patien ts had undergone periosteal excision. The risk of fracture, by Kaplan- Meier survivorship, was 29% at 5 years if the resection included perio steum (P < 0.0001), Cox multiple regression analysis showed that perio steal excision was the only independent prognostic factor for the enti re set of 205 patients at risk. However, for the subset of 54 patients who had periosteal stripping, two factors were also found to be progn ostically important: female gender (P = 0.022) and chemotherapy (P = 0 .020). The risk of fracture was 47% and 45%, respectively, The treatme nt of the fractures was difficult. There were four nonunions and three delayed unions. CONCLUSIONS. Periosteal stripping and radiation thera py places the femur at high risk of pathologic fractures, especially f or female patients and patients undergoing chemotherapy. When practica l, the combination of periosteal stripping and radiation should be avo ided. (C) 1998 American Cancer Society.