Nuclear Medicine Unit, IRCCS - Regina Elena National Cancer Institute, Via Elio Chianesi, 53, 00144, Rome, Italy.
First Division of Medical Oncology, IRCCS - Regina Elena National Cancer Institute, Rome, Italy.
Eur Radiol. 2021 Sep;31(9):7012-7021. doi: 10.1007/s00330-021-07841-w. Epub 2021 Mar 13.
The application of [F]FDG PET/CT in predicting histologic response to induction chemotherapy in patients with Ewing sarcoma (EWS) has been proposed using the values of pre-post treatment SUV as a referral parameter, although with heterogeneous results. The aim of this retrospective study was to evaluate the diagnostic accuracy of [F]FDG PET/CT volumetric parameters (metabolic tumour volume (MTV) and total lesion glycolysis (TLG)) as compared to SUV to predict response to chemotherapy and clinical outcome in patients with localised EWS of bone and soft-tissue.
Twenty-eight patients with non-metastatic EWS of bone (n = 20) and soft tissues (n = 8) who underwent a [F]FDG PET/CT scan before (PET) and after induction chemotherapy (PET) were enclosed in the analysis. Values of PET metrics (SUV, MTV, TLG) at diagnosis and after neoadjuvant chemotherapy as well as the percentage change between PET and PET (ΔSUV, ΔMTV and ΔTLG) were correlated to histological response and to progression-free survival (PFS).
ΔTLG (cut-off: -60%) is the best predictor for histologic response with 100% sensitivity and 77.8% specificity. MTV > 33.4 cm and TLG > 112 were also associated with a favourable histologic response (sensitivity 80% and specificity 77.8% for both). On multivariate analysis, SUV (> 3.3) and ΔTLG (< -18%) were independent predictors of worse PFS.
[F]FDG PET/CT could accurately predict histologic response to neoadjuvant chemotherapy in patients with EWS, also showing a possible prognostic value for future disease relapse.
• The variation of the PET parameter tumour lesion glycolysis (TLG) can predict the histologic response to induction chemotherapy (sensitivity 100%, specificity 77.8%), in patients with Ewing sarcoma. • The percentage variation of TLG and the value of the SUVmax at PET scan after chemotherapy show a prognostic role for future disease relapse. The combination of both the parameters identifies three prognostic classes of patients with low, intermediate and high risk of disease relapse.
已有研究提出，使用治疗前后 SUV 值作为参考参数，[F]FDG PET/CT 可预测尤文肉瘤（EWS）患者对诱导化疗的组织学反应，但结果存在差异。本回顾性研究旨在评估[F]FDG PET/CT 容积参数（代谢肿瘤体积（MTV）和总病变糖酵解（TLG））与 SUV 相比预测局部骨和软组织 EWS 患者对化疗反应和临床结局的诊断准确性。
共纳入 28 例接受[F]FDG PET/CT 扫描的非转移性骨（n = 20）和软组织（n = 8）EWS 患者，包括诊断时（PET）和诱导化疗后（PET）。将 PET 指标（SUV、MTV、TLG）在诊断时和新辅助化疗后的数值以及 PET 与 PET 之间的变化百分比（ΔSUV、ΔMTV 和 ΔTLG）与组织学反应和无进展生存期（PFS）相关联。
ΔTLG（截断值：-60%）是组织学反应的最佳预测指标，灵敏度为 100%，特异性为 77.8%。MTV＞33.4cm 和 TLG＞112 也与良好的组织学反应相关（灵敏度为 80%，特异性为 77.8%）。多变量分析显示，SUV（＞3.3）和ΔTLG（＜-18%）是 PFS 较差的独立预测因素。
[F]FDG PET/CT 可准确预测 EWS 患者新辅助化疗的组织学反应，且对未来疾病复发具有潜在的预后价值。
· 肿瘤病变糖酵解（TLG）的变化可以预测诱导化疗的组织学反应（灵敏度 100%，特异性 77.8%），在尤文肉瘤患者中。
· 化疗后 PET 扫描时 TLG 的百分比变化和 SUVmax 值显示出对未来疾病复发的预后作用。这两个参数的组合可将患者分为低、中、高疾病复发风险的三个预后组。
