From the Division of Systemic Autoimmune Diseases, Department of Internal Medicine, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
Department of Nuclear Medicine, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
Clin Nucl Med. 2021 Jun 1;46(6):e307-e311. doi: 10.1097/RLU.0000000000003537.
The aim of this study was to assess disease activity by different PET/CT measurements in IgG4-related disease (IgG4-RD) flares and their correlation with the IgG4-RD responder index (IgG4-RI).
Patients were retrospectively recruited from a single center in Barcelona, Spain. They all had IgG4-RD flares with an 18F-FDG PET/CT examination performed within the 2 first weeks of the flare onset and another one after at least 3 months of treatment between 2012 and 2018. Epidemiologic, clinical, laboratory, and therapeutic data were collected at baseline and at follow-up. Semiquantitative and volumetric measurements from PET/CT explorations were recorded. In addition, a 5-point visual scale was (adapted Deauville score) trialed. The IgG4-RI was used as the criterion standard to assess response before and after treatment.
Eighteen patients with a total of 23 flares were included. The median time to second PET/CT examination was 7 months. Remission (complete and partial) according to IgG4-RI was observed in 20 flares (87%). All PET/CT measurements (SUVmax and SUVmean, total lesion glycolysis, MTV, and adapted Deauville score) were statistically significantly lower on the follow-up evaluation, except for the size of the lesion. The correlation of all these parameters with the IgG4-RI was positive except for SUVmean and the size of the lesion.
Semiquantitative, volumetric, and visual parameters in PET/CT scans correlated with response to treatment assessed by IgG4-RI. Volumetric and visual items are less subject to variations and could be used to improve activity scores and treatment strategies.
本研究旨在评估 IgG4 相关疾病（IgG4-RD）活动度的不同 PET/CT 测量值及其与 IgG4-RD 应答指数（IgG4-RI）的相关性。
患者均来自西班牙巴塞罗那的一家单中心，均在 IgG4-RD 活动期的前 2 周内进行了 18F-FDG PET/CT 检查，且在活动期开始后至少 3 个月进行了另一次检查。在 2012 年至 2018 年期间，收集了患者的流行病学、临床、实验室和治疗数据。记录了 PET/CT 检查的半定量和容积测量值。此外，还试用了 5 分视觉量表（改良的 Deauville 评分）。IgG4-RI 用于治疗前后应答的标准。
共纳入 18 例患者的 23 次活动期。第二次 PET/CT 检查的中位时间为 7 个月。根据 IgG4-RI，20 次活动期（87%）观察到缓解（完全和部分）。除了病变的大小外，所有 PET/CT 测量值（SUVmax 和 SUVmean、总病变糖酵解、MTV 和改良的 Deauville 评分）在随访评估中均显著降低。除了 SUVmean 和病变的大小外，所有这些参数与 IgG4-RI 的相关性均为阳性。
PET/CT 扫描的半定量、容积和视觉参数与 IgG4-RI 评估的治疗反应相关。容积和视觉指标受变化影响较小，可用于改善活动评分和治疗策略。
