Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
J Nucl Med. 2017 Jun;58(6):920-925. doi: 10.2967/jnumed.116.178418. Epub 2016 Nov 10.
The objective of this study was to validate several parametric methods for quantification of 3'-deoxy-3'-F-fluorothymidine (F-FLT) PET in advanced-stage non-small cell lung carcinoma (NSCLC) patients with an activating epidermal growth factor receptor mutation who were treated with gefitinib or erlotinib. Furthermore, we evaluated the impact of noise on accuracy and precision of the parametric analyses of dynamic F-FLT PET/CT to assess the robustness of these methods. Ten NSCLC patients underwent dynamic F-FLT PET/CT at baseline and 7 and 28 d after the start of treatment. Parametric images were generated using plasma input Logan graphic analysis and 2 basis functions-based methods: a 2-tissue-compartment basis function model (BFM) and spectral analysis (SA). Whole-tumor-averaged parametric pharmacokinetic parameters were compared with those obtained by nonlinear regression of the tumor time-activity curve using a reversible 2-tissue-compartment model with blood volume fraction. In addition, 2 statistically equivalent datasets were generated by countwise splitting the original list-mode data, each containing 50% of the total counts. Both new datasets were reconstructed, and parametric pharmacokinetic parameters were compared between the 2 replicates and the original data. After the settings of each parametric method were optimized, distribution volumes (V) obtained with Logan graphic analysis, BFM, and SA all correlated well with those derived using nonlinear regression at baseline and during therapy ( ≥ 0.94; intraclass correlation coefficient > 0.97). SA-based V images were most robust to increased noise on a voxel-level (repeatability coefficient, 16% vs. >26%). Yet BFM generated the most accurate values ( = 0.94; intraclass correlation coefficient, 0.96). Parametric data showed a larger variability in general; however, no differences were found in robustness between methods (repeatability coefficient, 80%-84%). Both BFM and SA can generate quantitatively accurate parametric F-FLT V images in NSCLC patients before and during therapy. SA was more robust to noise, yet BFM provided more accurate parametric data. We therefore recommend BFM as the preferred parametric method for analysis of dynamic F-FLT PET/CT studies; however, SA can also be used.
本研究旨在验证几种用于定量分析晚期非小细胞肺癌（NSCLC）患者 3'-去氧-3'-F-氟代胸苷（F-FLT）正电子发射断层扫描（PET）的参数化方法，这些患者的表皮生长因子受体（EGFR）存在激活突变，接受吉非替尼或厄洛替尼治疗。此外，我们还评估了噪声对动态 F-FLT PET/CT 参数分析准确性和精密度的影响，以评估这些方法的稳健性。 10 例 NSCLC 患者在治疗开始前、第 7 天和第 28 天进行了 F-FLT 动态 PET/CT 检查。使用血浆输入 Logan 图形分析和 2 种基于基础函数的方法生成参数图像：2 组织室基础函数模型（BFM）和光谱分析（SA）。比较全肿瘤平均参数药代动力学参数与使用具有血容量分数的可逆 2 组织室模型对肿瘤时间-活性曲线进行非线性回归得到的参数。此外，通过对原始列表模式数据进行逐点分割，生成了 2 个统计等效的数据集，每个数据集包含总计数的 50%。对这两个新数据集进行重建，并比较了 2 个重复数据与原始数据之间的参数药代动力学参数。 在优化了每个参数方法的设置后，在基线和治疗期间，Logan 图形分析、BFM 和 SA 获得的分布容积（V）与使用非线性回归获得的 V 值高度相关（≥0.94；组内相关系数>0.97）。基于 SA 的 V 图像在体素水平上对噪声的稳健性最高（重复性系数，16%比>26%）。然而，BFM 生成了最准确的参数值（=0.94；组内相关系数，0.96）。参数数据通常显示出更大的变异性；然而，在方法之间，稳健性没有差异（重复性系数，80%-84%）。 BFM 和 SA 均可在 NSCLC 患者治疗前后生成定量准确的 F-FLT 参数 V 图像。SA 对噪声更稳健，但 BFM 提供了更准确的参数数据。因此，我们建议将 BFM 作为动态 F-FLT PET/CT 研究分析的首选参数方法；然而，也可以使用 SA。
