INTRODUCTION: There is growing interest in using positron emission tomography (PET) standardized uptake values (SUVs) to assess tumor response to therapy. However, many error sources compromise the ability to detect SUV changes. We explore relationships between these errors and overall SUV variability. METHODS: We used simulations in a virtual clinical trial framework to study impacts of error sources from scanning and analysis effects on assessment of SUV changes. We varied tumor diameter, scan duration, pretherapy SUV, magnitude of change in SUV, image reconstruction filter, and SUV metric. Poisson noise was added to the raw data before image reconstruction. Variance from global sources of error, e.g., scanner calibration, was incorporated. Two thousand independent noisy sinograms per scenario were generated and reconstructed. We used SUVs to create receiver operating characteristic (ROC) curves to quantify ability to assess response. Integrating area under the ROC curve summarized ability to detect SUV changes. RESULTS: Scan duration and image reconstruction method had relatively little impact on ability to measure response. SUV_MAX is nearly as effective as SUV_MEAN, especially with increased image smoothing and despite size-matched region of interest placement. For an effective variability of 15%, we found the Positron Emission Tomography Response Criteria in Solid Tumors criteria for measuring response (±30%) similar to the European Organization for Research and Treatment of Cancer criteria (±25%). CONCLUSIONS: For typical PET variance levels, tumor response must be 30% to 40% to be reliably determined using SUVs. PET scan duration and image reconstruction method had relatively little effect.

简介：使用正电子发射断层扫描 (PET) 标准化摄取值 (SUV) 来评估肿瘤对治疗的反应越来越受到关注。然而，许多错误源会影响检测 SUV 变化的能力。我们探讨了这些误差与整体 SUV 可变性之间的关系。方法：我们在虚拟临床试验框架中使用模拟来研究来自扫描和分析影响的误差源对 SUV 变化评估的影响。我们改变了肿瘤直径、扫描持续时间、治疗前 SUV、SUV 变化幅度、图像重建过滤器和 SUV 指标。在图像重建之前将泊松噪声添加到原始数据中。纳入了来自全局误差源的差异，例如扫描仪校准。生成和重建每个场景 2000 个独立的噪声正弦图。我们使用 SUV 创建受试者工作特征 (ROC) 曲线以量化评估反应的能力。ROC 曲线下的积分面积总结了检测 SUV 变化的能力。结果：扫描持续时间和图像重建方法对反应测量能力的影响相对较小。SUV _MAX几乎与 SUV _MEAN一样有效，尤其是在图像平滑度增加以及感兴趣区域大小匹配的情况下。对于 15% 的有效变异，我们发现实体瘤中的正电子发射断层扫描响应标准用于测量响应 (±30%) 类似于欧洲癌症研究和治疗组织的标准 (±25%)。结论：对于典型的 PET 变异水平，肿瘤反应必须为 30% 到 40% 才能使用 SUV 可靠地确定。PET 扫描持续时间和图像重建方法的影响相对较小。