Department of Nuclear Medicine, Ludwig-Maximilians-University, Munich, Germany.
J Nucl Med. 2010 Sep;51(9):1349-56. doi: 10.2967/jnumed.110.075002. Epub 2010 Aug 18.
We aimed to evaluate (68)Ga-DOTATATE PET/CT for the early prediction of time to progression and clinical outcome after a first cycle of peptide receptor radionuclide treatment (PRRT) in a cohort of patients with well-differentiated neuroendocrine tumors.
Thirty-three consecutive patients (22 men and 11 women; mean age +/- SD, 57.8 +/- 12.1 y) were investigated at baseline and again 3 mo after initiation of the first cycle of PRRT. (68)Ga-DOTATATE receptor expression was assessed using 2 measures of standardized uptake value (SUV): maximum SUV (SUV(max)) and tumor-to-spleen SUV ratio (SUV(T/S)). Percentage change in SUV scores after PRRT relative to baseline (DeltaSUV) was calculated. After completing 1-3 cycles of PRRT, patients entered the follow-up study, for estimation of time to progression. According to the Response Evaluation Criteria in Solid Tumors, progression was defined on the basis of contrast-enhanced CT. Clinical symptoms, as well as the tumor markers chromogranin A and neuron-specific enolase, were also recorded during regular follow-up visits.
The 23 of 31 patients with decreased SUV(T/S) after the first PRRT cycle had longer progression-free survival than did the 8 of 31 patients with stable or increased scores (median survival not reached vs. 6 mo, P = 0.002). For the 18 of 33 patients showing a reduction in SUV(max), there was no significant difference in progression-free survival (median survival not reached vs. 14 mo, P = 0.22). Multivariate regression analysis identified SUV(T/S) as the only independent predictor for tumor progression during follow-up. In the 17 of 33 patients with clinical symptoms before PRRT, DeltaSUV(T/S) correlated with clinical improvement (r = 0.52, P < 0.05), whereas DeltaSUV(max) did not (r = 0.42, P = 0.10). Changes in the tumor markers (chromogranin A and neuron-specific enolase) did not predict DeltaSUV scores, clinical improvement, or time to progression.
Decreased (68)Ga-DOTATATE uptake in tumors after the first cycle of PRRT predicted time to progression and correlated with an improvement in clinical symptoms among patients with well-differentiated neuroendocrine tumors; DeltaSUV(T/S) was superior to DeltaSUV(max) for prediction of outcome.
评估（68）Ga-DOTATATE PET/CT 在一组分化良好的神经内分泌肿瘤患者接受肽受体放射性核素治疗（PRRT）第一周期后，对进展时间和临床结局的早期预测价值。
33 例连续患者（22 例男性和 11 例女性；平均年龄 +/- 标准差，57.8 +/- 12.1 岁）在基线和 PRRT 第一周期开始后 3 个月时进行了评估。使用两种标准化摄取值（SUV）测量（68）Ga-DOTATATE 受体表达：最大 SUV（SUV(max)）和肿瘤与脾脏 SUV 比值（SUV(T/S)）。计算 PRRT 后与基线相比 SUV 评分的变化百分比（DeltaSUV）。完成 1-3 个周期的 PRRT 后，患者进入随访研究，以估计进展时间。根据实体瘤反应评估标准，根据增强 CT 定义进展。在常规随访中还记录了临床症状以及嗜铬粒蛋白 A 和神经元特异性烯醇化酶等肿瘤标志物。
31 例患者中，23 例在第一周期 PRRT 后 SUV(T/S)下降者的无进展生存期长于 SUV(T/S)稳定或升高者（31 例）（中位无进展生存期未达到与 6 个月，P = 0.002）。在 33 例 SUV(max)降低的患者中，无进展生存期无显著差异（中位无进展生存期未达到与 14 个月，P = 0.22）。多变量回归分析表明，SUV(T/S)是随访期间肿瘤进展的唯一独立预测因子。在 33 例有 PRRT 前临床症状的患者中，DeltaSUV(T/S)与临床改善相关（r = 0.52，P < 0.05），而 DeltaSUV(max)则没有（r = 0.42，P = 0.10）。肿瘤标志物（嗜铬粒蛋白 A 和神经元特异性烯醇化酶）的变化不能预测 DeltaSUV 评分、临床改善或进展时间。
PRRT 第一周期后肿瘤（68）Ga-DOTATATE 摄取减少可预测进展时间，并与分化良好的神经内分泌肿瘤患者的临床症状改善相关；DeltaSUV(T/S)优于 DeltaSUV(max)，可预测预后。
