Objectives To evaluate the clinical efficacy of a dual-low-dose total-body PET/CT protocol in pediatric lymphoma patients, incorporating low-dose PET imaging in combination with two distinct low-dose CT acquisition strategies. Materials and methods Pediatric lymphoma patients (≤ 18 years) receiving half-dose [18F]FDG (1.85 ± 0.2 MBq/kg) were prospectively enrolled and divided into low-dose CT group (LDCT) and ultra-low-dose CT group (ULDCT) using uEXPLORER scanner. Image quality was evaluated based on subjective and objective metrics. The reference standard of lesions was confirmed with pathological and follow-up evidence. The effective dose (ED), the diagnostic efficacy for detecting lesions, and the accuracy for staging, treatment responses were compared. Institutional Review Board approval was obtained. Results A total of 246 pediatric patients were enrolled (9.2 ± 3.8 years, 180 male). The LDCT (n = 127) and ULDCT (n = 119) had similar clinical characteristics (p > 0.05) except for male percentage (78.7% vs. 67.2%, p = 0.042). The total ED of ULDCT was significantly lower than that of LDCT (5.6 ± 1.9 mSv vs. 9.7 ± 3.2 mSv, p < 0.001). Both groups showed acceptable subject image quality and were comparable in main objective parameters. ULDCT showed a sensitivity lower than LDCT (99.0% vs. 99.9%, p = 0.010) in diagnosing lymph node lesions, while their specificity (96.0% vs. 94.3%) and area under curve (AUC, 0.978 vs. 0.982) were similar (both p > 0.05). LDCT and ULDCT were also comparable in diagnosing extranodal involvements (AUCs > 0.800), staging accuracy (94.6% and 93.6%), and response assessment accuracy (97.6% and 96.3%). Conclusions Dual-low-dose total-body PET/CT allowed a significant reduction in total ED without compromising imaging quality and diagnosis performance in pediatric lymphoma patients. Key Points <Emphasis Type="BoldItalic">Question</Emphasis> [18F]FDG PET/CT scans are crucial for pediatric lymphoma patients; however, an optimized low-dose strategy has not been achieved. <Emphasis Type="BoldItalic">Findings</Emphasis> Dual-low-dose PET/CT demonstrated sufficient image quality and clinical efficacy in pediatric lymphoma patients, with significantly reduced radiation exposure. The total radiation dosage of the ultra-low-dose CT protocol was 5.6 ± 1.9 mSv. <Emphasis Type="BoldItalic">Clinical relevance</Emphasis> A dual-low-dose PET/CT protocol is an optimized imaging strategy for pediatric lymphoma patients that significantly reduces radiation exposure while providing sufficient clinical efficacy for diagnosing, staging and treatment response evaluation. Graphical Abstract

Significant dose reduction employing dual-low-dose PET/CT in pediatric lymphoma: maintaining diagnostic, staging, and response-assessing efficacy

期刊论文
发表日期：

2025年8月15日

查看全文

Yuqian Huang,
Si Tang,
Tianquan Wang,
Shatong Li,
Liuyi Cao,
Wanqi Chen,
Lei Liu,
Tingfan Wu,
Yumo Zhao,
Wei Fan,
Yinghe Li,
Yizhuo Zhang,
Yingying Hu

摘要

Objectives

To evaluate the clinical efficacy of a dual-low-dose total-body PET/CT protocol in pediatric lymphoma patients, incorporating low-dose PET imaging in combination with two distinct low-dose CT acquisition strategies.

Materials and methods

Pediatric lymphoma patients (≤ 18 years) receiving half-dose [¹⁸F]FDG (1.85 ± 0.2 MBq/kg) were prospectively enrolled and divided into low-dose CT group (LDCT) and ultra-low-dose CT group (ULDCT) using uEXPLORER scanner. Image quality was evaluated based on subjective and objective metrics. The reference standard of lesions was confirmed with pathological and follow-up evidence. The effective dose (ED), the diagnostic efficacy for detecting lesions, and the accuracy for staging, treatment responses were compared. Institutional Review Board approval was obtained.

Results

A total of 246 pediatric patients were enrolled (9.2 ± 3.8 years, 180 male). The LDCT (n = 127) and ULDCT (n = 119) had similar clinical characteristics (p > 0.05) except for male percentage (78.7% vs. 67.2%, p = 0.042). The total ED of ULDCT was significantly lower than that of LDCT (5.6 ± 1.9 mSv vs. 9.7 ± 3.2 mSv, p < 0.001). Both groups showed acceptable subject image quality and were comparable in main objective parameters. ULDCT showed a sensitivity lower than LDCT (99.0% vs. 99.9%, p = 0.010) in diagnosing lymph node lesions, while their specificity (96.0% vs. 94.3%) and area under curve (AUC, 0.978 vs. 0.982) were similar (both p > 0.05). LDCT and ULDCT were also comparable in diagnosing extranodal involvements (AUCs > 0.800), staging accuracy (94.6% and 93.6%), and response assessment accuracy (97.6% and 96.3%).

Conclusions

Dual-low-dose total-body PET/CT allowed a significant reduction in total ED without compromising imaging quality and diagnosis performance in pediatric lymphoma patients.

Key Points

Question [¹⁸F]FDG PET/CT scans are crucial for pediatric lymphoma patients; however, an optimized low-dose strategy has not been achieved.

Findings Dual-low-dose PET/CT demonstrated sufficient image quality and clinical efficacy in pediatric lymphoma patients, with significantly reduced radiation exposure. The total radiation dosage of the ultra-low-dose CT protocol was 5.6 ± 1.9 mSv.

Clinical relevance A dual-low-dose PET/CT protocol is an optimized imaging strategy for pediatric lymphoma patients that significantly reduces radiation exposure while providing sufficient clinical efficacy for diagnosing, staging and treatment response evaluation.

Graphical Abstract