Hanafi Hanis, Freeman Carolyn R, Tsui James, Ramia Paul, Turcotte Robert, Aoude Ahmed, Bozzo Anthony, Cury Fabio L
Department of Oncology, Division of Radiation Oncology, McGill University Hospital Centre, Montreal, Quebec, Canada.
Department of Orthopaedics, McGill University Hospital Centre, Montreal, Quebec, Canada.
Pract Radiat Oncol. 2025 Mar-Apr;15(2):e189-e197. doi: 10.1016/j.prro.2024.10.008. Epub 2024 Oct 30.
We aimed to determine if ultrahypofractionated radiation therapy (UHYPO-RT) delivering 6 Gy x 5 fractions yields similar tumor necrosis compared with conventional radiation therapy (CONV-RT) with 2 Gy x 25 fractions in soft tissue sarcoma. The clinical significance of tumor necrosis on loco-regional recurrence-free survival (LRFS), distant disease-free survival (DDFS), and overall survival (OS) were assessed.
Patients with localized soft tissue sarcoma treated with CONV-RT or UHYPO-RT followed by surgery were included. Good response was defined as tumor necrosis ≥90%, and poor response as <90%. The Mann-Whitney U test compared median tumor necrosis. χ analysis was used for categorical variables. The Kaplan-Meier function estimated LRFS, DDFS, and OS.
A total of 64 patients received CONV-RT, and 45 received UHYPO-RT. The median tumor size was 7.0 cm, with the lower extremity being the most common site (55%). Myxofibrosarcoma (39%) and undifferentiated pleomorphic sarcoma (16%) were the most frequent histologies. The median time from radiation therapy to surgery was 35 days. There was a significant difference in median tumor necrosis between CONV-RT and UHYPO-RT, with rates of 40% and 60%, respectively (P = .022). Patients receiving UHYPO-RT had a higher percentage of tumor necrosis at the 90% cutoff, achieving 27% compared with 6% for CONV-RT (P = .003). At a median follow-up of 32 months, 12 patients (9%) experienced loco-regional recurrence, 24 patients (19%) faced distant failure, and 19 patients (15%) died of metastatic disease. Patients with <90% necrosis had higher rates of loco-regional (13% vs 0%, P = .207) and distant failure (25% vs 0%, P = .021). Three-year LRFS was 86% for <90% necrosis and 100% for ≥90% necrosis (P = .160). DDFS was 75% for <90% necrosis versus 100% for ≥90% (P = .036). OS rates were 79% and 93%, respectively (P = .290).
Preoperative RT with UHYPO-RT was associated with a higher rate of tumor necrosis ≥90% than CONV-RT. Our data suggest that more extensive necrosis is associated with better clinical outcomes.
我们旨在确定在软组织肉瘤中，给予6 Gy×5次分割的超分割放疗（UHYPO-RT）与给予2 Gy×25次分割的传统放疗（CONV-RT）相比，是否能产生相似的肿瘤坏死情况。评估肿瘤坏死对局部区域无复发生存率（LRFS）、远处无病生存率（DDFS）和总生存率（OS）的临床意义。
纳入接受CONV-RT或UHYPO-RT治疗后行手术的局限性软组织肉瘤患者。良好反应定义为肿瘤坏死≥90%，不良反应定义为<90%。采用曼-惠特尼U检验比较肿瘤坏死中位数。χ分析用于分类变量。采用Kaplan-Meier函数估计LRFS、DDFS和OS。
共有64例患者接受CONV-RT，45例接受UHYPO-RT。肿瘤中位大小为7.0 cm，最常见部位为下肢（55%）。黏液纤维肉瘤（39%）和未分化多形性肉瘤（16%）是最常见的组织学类型。从放疗到手术的中位时间为35天。CONV-RT和UHYPO-RT的肿瘤坏死中位数存在显著差异，分别为40%和60%（P = 0.022）。接受UHYPO-RT的患者在肿瘤坏死率≥90%时的比例更高，达到27%，而CONV-RT为6%（P = 0.003）。中位随访32个月时，12例患者（9%）出现局部区域复发，24例患者（19%）出现远处转移，19例患者（15%）死于转移性疾病。坏死<90%的患者局部区域复发率（13% vs 0%，P = 0.207）和远处转移率（25% vs 0%，P = 0.021）更高。坏死<90%的患者三年LRFS为86%，坏死≥90%的患者为100%（P = 0.160）。DDFS在坏死<90%的患者中为75%，在坏死≥90%的患者中为100%（P = 0.036）。OS率分别为79%和93%（P = 0.290）。
术前采用UHYPO-RT放疗比CONV-RT产生≥90%肿瘤坏死的发生率更高。我们的数据表明，更广泛的坏死与更好的临床结果相关。
