Departments of Nuclear Medicine.
Medical Imaging.
Nucl Med Commun. 2021 Jul 1;42(7):747-754. doi: 10.1097/MNM.0000000000001395.
90Y-radioembolization using glass or resin microspheres is increasingly used for the treatment of hepatocellular carcinoma (HCC). The aim of this retrospective study is to determine the prognostic relevance of dosimetric parameters defined with 90Y-PET-CT obtained immediately after radioembolization.
Forty-five HCC patients, mostly with multiple lesions, were treated by radioembolization between 2011 and 2017. After treatment, all underwent a 90Y PET-CT with time of flight reconstruction (90Y-TOF-PET-CT). Tumor absorbed dose and cumulative tumor dose-volume histogram were calculated using a dose point Kernel convolution algorithm. The radiological tumor response was assessed using modified (m)-RECIST criteria. Progression-free-survival (PFS) and overall survival (OS) were analyzed using the Kaplan-Meier method and Cox regression analysis.
Twenty-six patients were treated with glass microspheres (73 lesions) and nineteen with resin microspheres (60 lesions). Thresholds of 118 and 61 Gy for glass and resin microspheres respectively correlate well with radiological response with a positive predictive value (PPV) of 98 and 80% and discriminate patient outcome with regard to PFS (P = 0.03 and 0.005) and OS (P = 0.003 and 0.007). Using dose volume histogram, a minimal absorbed dose of 40 Gy in 66% of the tumor volume (defined as D66) was highly predictive of radiological response (PPV = 94%), PFS (P < 0.001) and OS (P = 0. 008), for either device.
Dosimetric parameters obtained using 90Y-PET-CT are predictive of tumor response, PFS and OS. In clinical practice, a systematic dosimetric evaluation using 90Y PET should be implemented to help predicting patient outcomes.
90Y 放射性栓塞治疗使用玻璃或树脂微球治疗肝细胞癌（HCC）的应用日益增多。本回顾性研究旨在确定即刻行 90Y-PET-CT 检查所获得的剂量学参数与预后的相关性。
2011 年至 2017 年间，45 例 HCC 患者（多数患者存在多发病灶）接受了放射性栓塞治疗。治疗后，所有患者均进行了一次 90Y 飞行时间重建 PET-CT（90Y-TOF-PET-CT）检查。采用剂量点核卷积算法计算肿瘤吸收剂量和累积肿瘤剂量-体积直方图。采用改良（m）-RECIST 标准评估肿瘤的放射学反应。采用 Kaplan-Meier 法和 Cox 回归分析评估无进展生存期（PFS）和总生存期（OS）。
26 例患者接受玻璃微球（73 个病灶）治疗，19 例患者接受树脂微球（60 个病灶）治疗。玻璃微球和树脂微球的阈值分别为 118Gy 和 61Gy，与放射学反应具有良好的相关性，阳性预测值（PPV）分别为 98%和 80%，可根据 PFS（P=0.03 和 0.005）和 OS（P=0.003 和 0.007）区分患者的预后。采用剂量体积直方图，肿瘤体积 66%（D66）的最小吸收剂量 40Gy 对放射学反应具有高度预测性（PPV=94%）、PFS（P<0.001）和 OS（P=0.008），对两种设备均适用。
90Y-PET-CT 获得的剂量学参数可预测肿瘤反应、PFS 和 OS。在临床实践中，应系统地采用 90Y-PET 进行剂量评估，以帮助预测患者的预后。
