2268 - Long-Term Toxicity in High-Risk Soft Tissue Sarcoma Treated with Neoadjuvant Hypofractionated Chemoradiation: A Single-Institution Retrospective Series
Presenter(s)
J. A. Weisberg1, C. W. Ryan2, K. R. Gundle3, L. Davis2, A. Y. Hung1, and C. M. Post1; 1Department of Radiation Medicine, Oregon Health & Science University, Portland, OR, 2Division of Hematology and Medical Oncology, Department of Medicine, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, 3Department of Orthopaedics and Rehabilitation, Oregon Health & Science University, Portland, OR
Purpose/Objective(s): Neoadjuvant chemoradiation (CRT) prior to surgical resection in soft tissue sarcoma (STS) of the extremity or body wall is often employed for patients at high-risk for distant metastatic disease. Neoadjuvant CRT for STS is associated with a toxicity profile that can be affected by different dose-fractionation regimens. In some practices, hypofractionated radiotherapy courses are utilized instead of longer conventional radiation regimens. We conducted this retrospective chart review to evaluate chemoradiation toxicities after surgery in patients treated with neoadjuvant hypofractionated CRT at our institution.
Materials/Methods: Data for this retrospective chart review was collected from 45 consecutive patients with localized, intermediate or high-grade STS of the extremity or body wall, who were treated with neoadjuvant hypofractionated CRT between 2014-2022. All patients had at least 2 years of follow-up. Radiation was 28 Gy in 8 fractions, and concurrent systemic therapy included Epirubicin/Ifosfamide +/- Sorafinib. Primary toxicities were collected through chart review and included major wound complications (WC) requiring surgical intervention as defined in the SR-2 trial, bone events such as fracture, and limb amputation. Systemic therapy adherence was documented and WC based on systemic therapy regimen were delineated. Chi square analysis was used to evaluate the statistical relationship between anatomic tumor site and major WC, with statistical significance set at p < 0.05.
Results: Median follow-up was 74 months. Most patients had T3 or T4 tumors (60%) and had negative margin surgeries (93%). 22/45 (48%) STS patients experienced major wound complications. Most major WC occurred in patients with lower extremity (17/29, 59%) or torso/trunk (4/7, 57%) STS. There was a significant association between anatomic tumor site and major WC, (X^2 = 6.43, p = 0.04). Bone events occurred in 2/45 (4%) of STS patients, and included a pubic stress fracture and need for prophylactic femoral nailing. Limb amputation was required in 2/45 (4%) cases, one related to disease progression, one due to disease recurrence. Five-year oncologic outcomes have been previously reported with this CRT regimen.
Conclusion: STS treated with neoadjuvant hypofractionated CRT are associated with major WC rates that are comparable to slightly higher than standard neoadjuvant radiation regimens without concurrent chemotherapy. Tumor location site was significantly associated with major WC. Bone events and need for salvage limb amputation rates were low. This treatment regimen offers favorable clinical outcomes for well-selected patients with high-risk STS, albeit with increased major WC rates.