Division of Diagnostic Imaging, Department of Abdominal Imaging, The University of Texas MD Anderson Cancer Center, Houston, 1515 Holcombe Blvd, Houston, TX, 77030, USA.
Division of Internal Medicine, Section of Nephrology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Eur Radiol. 2023 Mar;33(3):2227-2238. doi: 10.1007/s00330-022-09158-8. Epub 2022 Oct 18.
Imaging appearances of immune checkpoint inhibitor-related nephritis have not yet been described. The primary objective of this study is to describe the appearances of immunotherapy-related nephritis on computerized tomography (CT) and positron emission tomography (PET). The secondary objectives are to investigate the association of radiologic features with clinical outcomes.
CT and PET-CT scans before the initiation of immunotherapy (baseline), at nephritis, and after resolution of pathology-proven nephritis cases were reviewed. Total kidney volume, renal parenchymal SUVmax, renal pelvis SUVmax, and blood pool SUVmean were obtained.
Thirty-four patients were included. The total kidney volume was significantly higher at nephritis compared to baseline (464.7 ± 96.8 mL vs. 371.7 ± 187.7 mL; p < 0.001). Fifteen patients (44.1%) had > 30% increase in total kidney volume, which was associated with significantly higher renal toxicity grade (p = 0.007), higher peak creatinine level (p = 0.004), and more aggressive medical treatment (p = 0.011). New/increasing perinephric fat stranding was noted in 10 patients (29.4%) at nephritis. Among 8 patients with contrast-enhanced CT at nephritis, one (12.5%) developed bilateral wedge-shaped hypoenhancing cortical. On PET-CT, the renal parenchymal SUVmax-to-blood pool ratio was significantly higher at nephritis compared to baseline (2.13 vs. 1.68; p = 0.035). The renal pelvis SUVmax-to-blood pool SUVmean ratio was significantly lower at nephritis compared to baseline (3.47 vs. 8.22; p = 0.011).
Bilateral increase in kidney size, new/increasing perinephric stranding, and bilateral wedge-shaped hypoenhancing cortical foci can occur in immunotherapy-related nephritis. On PET-CT, a diffuse increase in radiotracer uptake throughout the renal cortex and a decrease in radiotracer activity in the renal pelvis can be seen.
• CT features of immune checkpoint inhibitor-related nephritis include an increase in kidney volume, new/increasing perinephric stranding, and bilateral ill-defined wedge-shaped hypoenhancing cortical foci. • FDG-PET features of immune checkpoint inhibitor-related nephritis include an increase in FDG uptake throughout the renal cortex and a decrease in FDG activity/excretion in the collecting system. • > 30% increase in total kidney volume is associated with worse toxicity grade and more aggressive medical management.
免疫检查点抑制剂相关肾炎的影像学表现尚未得到描述。本研究的主要目的是描述计算机断层扫描（CT）和正电子发射断层扫描（PET）中免疫治疗相关肾炎的表现。次要目的是研究放射学特征与临床结局的关系。
回顾了免疫治疗前（基线）、肾炎时和经病理证实肾炎病例缓解后的 CT 和 PET-CT 扫描。获得总肾体积、肾实质 SUVmax、肾盂 SUVmax 和血池 SUVmean。
共纳入 34 例患者。与基线相比，肾炎时总肾体积明显升高（464.7±96.8ml 比 371.7±187.7ml；p＜0.001）。15 例患者（44.1%）总肾体积增加＞30%，与肾毒性分级显著升高相关（p=0.007）、峰值肌酐水平更高（p=0.004）和更积极的药物治疗（p=0.011）。肾炎时 10 例（29.4%）患者出现新出现/增加的肾周脂肪条纹。在肾炎时进行增强 CT 的 8 例患者中，1 例（12.5%）出现双侧楔形低增强皮质。在 PET-CT 上，肾炎时肾实质 SUVmax 与血池 SUVmean 比值明显高于基线（2.13 比 1.68；p=0.035）。肾盂 SUVmax 与血池 SUVmean 比值在肾炎时明显低于基线（3.47 比 8.22；p=0.011）。
免疫治疗相关肾炎可出现双侧肾脏增大、新出现/增加的肾周条纹和双侧楔形低增强皮质灶。在 PET-CT 上，可观察到整个肾皮质放射性示踪剂摄取增加，肾盂放射性示踪剂活性降低。
• CT 表现包括肾体积增大、新出现/增加的肾周条纹和双侧边界不清的楔形低增强皮质灶。• 免疫检查点抑制剂相关肾炎的 FDG-PET 表现包括整个肾皮质 FDG 摄取增加和集合系统 FDG 活性/排泄减少。• 总肾体积增加＞30%与毒性分级更差和更积极的药物治疗相关。
