SURGICAL OUTCOMES IN PATIENTS TREATED WITH FIVE-DAY PREOPERATIVE RADIOTHERAPY FOR HIGH-RISK PRIMARY SOFT-TISSUE SARCOMA

Standard of care treatment for high-risk soft tissues sarcoma (STS) of the extremity/trunk includes radiation therapy (RT) and surgical resection. At our center, initial results of a phase II single arm trial of 5-day preoperative RT demonstrated safety and local control comparable to conventional 5-week preoperative RT. The purpose of this study is to assess surgical outcomes and complications in patients undergoing 5-day preoperative RT (30 Gy) followed by surgical resection for high-risk STS of the extremity/trunk. Patients meeting criteria were consented and enrolled in a prospective phase II trial and received preoperative hypofractionated RT (30 Gy over 5 consecutive daily fractions) followed by surgical resection within an average of 4 weeks. Demographic variables included age, sex, diabetes, and smoking status. Tumor variables included: histology, location, and size. Surgical outcomes included rate of limb salvage, bony complications, soft tissue complications after primary surgery (dermatitis, superficial infection, deep infection, drainage, and dehiscence), margin status and rate and type of re-operation. Minimum post-operative follow-up was 3 months. Demographic data was presented with descriptive statistics, with mean and standard deviation (SD) or median and interquartile range (IQR) depending on the data distribution. Dichotomous variables were compared using the Fischer's exact test. A total of 94 patients were included with a mean age of 57.1 (SD 17.2): 41 (44%) were female, 10 (11%) were diabetic, and 8 patients (9%) had a significant smoking history. Median follow up was 23.7 months. The most common diagnosis was undifferentiated pleomorphic sarcoma (39.4%), then myxoid liposarcoma (23.4%), and myxofibrosarcoma (8.5%). The most common location was the lower extremity (60.6%), then upper extremity (18.1%), pelvis/trunk (17.0%), and ‘other’ (4.3%). Primary wound closure was achieved in 93 patients (98.9%). Twenty-seven (28.7%) cases required local tissue advancement for closure. Residual tumor status included 3 (3.2%) R2 resections, 16 (14.9%) R1 resections, and 77 (81.9%) R0 resections. Twenty-six (27.7%) patients experienced soft-tissue complications with wound dehiscence occurring in 18 patients (19.1%) at a median of 43.5 days (IQR 40.3–85.3) from surgery. Bony complications occurred in 4 patients: 3 pathologic fractures, and 1 osteonecrosis requiring surgery. Rate of limb salvage was 95.7%: 4/94 patients underwent amputation for disease progression at an average of 229.5 days (range: 140–398). Twenty-eight patients (29.8%) required secondary surgery at a mean of 201.07 days from index surgery (range: 5–1,708), including 14 irrigation and debridements, 7 re-excisions, and 8 applications of wound VAC. Patients requiring local soft tissue advancement for primary closure had more soft tissue complications (44.4% vs. 20.8%, p = 0.04). Soft tissue complications were not worse in patients having surgery within 2 weeks of RT (28.5% vs. 27.5%, p = 1). Even upon a more granular analysis, perioperative soft tissue and bony complications for patients with primary STS undergoing surgical resection following 5-day preoperative RT remain low and comparable to conventional 5-week preoperative RT, with a high rate (96%) of limb salvage. Soft tissue complications were higher among patients requiring local soft tissue advancement for wound closure.