Background:RT-induced hyalinization/fibrosis was recently evidenced as a significant independent predictor for complete response to neoadjuvant radiotherapy (RT) and survival in patients with soft tissue sarcoma (STS).Purpose:Non-invasive predictive markers of histologic response after neoadjuvant RT of STS are expected.Materials and Methods:From May 2010 to April 2017, patients with a diagnosis of STS who underwent neoadjuvant RT for limb STS were retrieved from a single center prospective clinical imaging database. Tumor Apparent Diffusion Coefficients (ADC) and areas under the time-intensity perfusion curve (AUC) were compared with the histologic necrosis ratio, fibrosis, and cellularity in post-surgical specimens.Results:We retrieved 29 patients. The median ADC value was 134.3 × 10−3mm2/s. ADC values positively correlated with the post-treatment tumor necrosis ratio (p= 0.013). Median ADC values were lower in patients with less than 50% necrosis and higher in those with more than 50% (120.3 × 10−3mm2/s and 202.0 × 10−3mm2/s, respectively (p= 0.020). ADC values higher than 161 × 10−3mm2/s presented a 95% sensitivity and a 55% specificity for the identification of tumors with more than 50% tumor necrosis ratio. Tumor-to-muscle AUC ratios were associated with histologic fibrosis (p= 0.036).Conclusions:ADC and perfusion AUC correlated, respectively, with radiation-induced tumor necrosis and fibrosis.
背景：近期研究表明，放疗诱导的透明样变性/纤维化是软组织肉瘤患者对新辅助放疗完全应答及生存率的显著独立预测因子。目的：亟需开发软组织肉瘤新辅助放疗后组织学应答的无创预测标志物。材料与方法：本研究从单中心前瞻性临床影像数据库中，提取2010年5月至2017年4月期间经病理确诊为肢体软组织肉瘤并接受新辅助放疗的患者数据。通过比较肿瘤表观扩散系数值及时间-强度灌注曲线下面积，与术后标本的组织学坏死率、纤维化程度及细胞密度进行相关性分析。结果：共纳入29例患者。中位ADC值为134.3×10⁻³mm²/s。ADC值与治疗后肿瘤坏死率呈正相关（p=0.013）。坏死率低于50%的患者中位ADC值（120.3×10⁻³mm²/s）显著低于坏死率高于50%的患者（202.0×10⁻³mm²/s）（p=0.020）。当ADC阈值设为161×10⁻³mm²/s时，对识别肿瘤坏死率超过50%的病例具有95%的敏感性和55%的特异性。肿瘤与肌肉的AUC比值与组织学纤维化程度相关（p=0.036）。结论：ADC值与灌注AUC分别与放疗诱导的肿瘤坏死和纤维化具有显著相关性。
肿瘤(癌症)患者之家