Gu Taoying, Liu Siwei, Hou Xiaoguang, Zhao Liwei, Ng Yee Ling, Wang Jingyi, Shi Hongcheng
Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, 180 Fenglin Road, 200032, Shanghai, People's Republic of China.
Nuclear Medicine Institute of Fudan University, 200032, Shanghai, China.
Eur Radiol. 2025 Apr;35(4):1881-1893. doi: 10.1007/s00330-024-11039-1. Epub 2024 Aug 30.
Implementing personalization protocol in clinical routine necessitates diverse low-dose PET/CT scan protocols. This study explores the clinical feasibility of one-third (1/3) dose regimen and evaluates the diagnostic image quality and lesion detectability of BMI-based 1/3-injection doses for 2-[F]FDG PET/CT imaging.
Seventy-four cancer patients underwent total-body 2-[F]FDG PET/CT examination, with 37 retrospectively enrolled as full-dose group (3.7 MBq/kg) and 37 prospectively enrolled as the 1/3-dose group (1.23 MBq/kg). The 1/3-dose group was stratified by BMI, with an acquisition time of 5 min (G5), 6 min (G6), and 8 min (G8) for BMI < 25, 25 ≤ BMI ≤ 29, and BMI > 29, respectively. Image quality was subjectively and objectively assessed, and lesion detectability was quantitatively analyzed.
Subjective assessments of 1/3-dose and full-dose PET images showed strong agreement among readers (κ > 0.88). In the 1/3-dose group, the Likert scores were above 4. G5, G6, and G8 showed comparable image quality, with G5 demonstrating higher lesion conspicuity than G6 and G8 (p = 0.045). Objective evaluation showed no significant differences in SUV, liver SUV and TBR between 1/3- and full-dose groups (p > 0.05). No statistical differences were observed in the SUV of primary tumor, SUV of liver and TBR across all BMI categories between the 1/3-dose and full-dose groups. Lesion detection rates showed no significant difference between the 1/3-dose (93.24%, 193/207) and full-dose groups (94.73%, 198/209) (p = 0.520).
A BMI-stratified 1/3-dose regimen is a feasible low-dose alternative with clinically acceptable lesion detectability equivalent to full-dose protocol, potentially expanding the applicability of personalized protocols.
This study demonstrated that BMI-stratified 1/3-dose regimens for [F]FDG total-body PET/CT yielded equivalent outputs compared to the full-dose regimen, which aligns with clinical needs for personalization in dose and BMI.
Currently, limited personalized low-dose total-body PET/CT protocols are available, particularly for patients with varied BMI. Reducing the radiotracer dose to 1/3 the standard demonstrated comparable image quality and lesion detectability equivalent to full dose. BMI-stratified 1/3-dose regimen is a clinically feasible low-dose alternative.
在临床常规中实施个性化方案需要多种低剂量PET/CT扫描方案。本研究探讨三分之一（1/3）剂量方案的临床可行性，并评估基于BMI的1/3注射剂量用于2-[F]FDG PET/CT成像的诊断图像质量和病变可检测性。
74例癌症患者接受了全身2-[F]FDG PET/CT检查，其中37例回顾性纳入全剂量组（3.7 MBq/kg），37例前瞻性纳入1/3剂量组（1.23 MBq/kg）。1/3剂量组按BMI分层，BMI＜25、25≤BMI≤29和BMI＞29时的采集时间分别为5分钟（G5）、6分钟（G6）和8分钟（G8）。对图像质量进行主观和客观评估，并对病变可检测性进行定量分析。
1/3剂量和全剂量PET图像的主观评估显示，阅片者之间具有高度一致性（κ＞0.88）。在1/3剂量组中，Likert评分高于4分。G5、G6和G8组的图像质量相当，G5组的病变清晰度高于G6组和G8组（p = 0.045）。客观评估显示，1/3剂量组和全剂量组之间的SUV、肝脏SUV和TBR无显著差异（p＞0.05）。1/3剂量组和全剂量组在所有BMI类别中的原发肿瘤SUV、肝脏SUV和TBR均无统计学差异。病变检出率在1/3剂量组（93.24%，193/207）和全剂量组（94.73%，198/209）之间无显著差异（p = 0.520）。
基于BMI分层的1/3剂量方案是一种可行的低剂量替代方案，其病变可检测性在临床上可接受，与全剂量方案相当，可能会扩大个性化方案的适用性。
本研究表明，用于[F]FDG全身PET/CT的基于BMI分层的1/三弟量方案与全剂量方案产生的结果相当，这符合剂量和BMI个性化的临床需求。
目前，可用的个性化低剂量全身PET/CT方案有限，尤其是对于BMI不同的患者。将放射性示踪剂剂量降低至标准剂量的1/3显示出与全剂量相当的图像质量和病变可检测性。基于BMI分层的1/3剂量方案是一种临床上可行的低剂量替代方案。
