Langerhans细胞组织细胞病（LCH）是一种罕见的骨髓前体细胞炎性肿瘤，会使患者受苦，伤残甚至死亡。尽管近几十年来临床结果不断改善，但LCH的进展/复发率仍然很高。本研究的目的是评估基线18F-氟脱氧葡萄糖正电子发射计算机断层扫描/计算机断层扫描（18F‑FDG PET/CT）的预处理代谢参数对儿童LCH的预后价值。这项横断面研究回顾性连续纳入了2020年9月至2022年9月期间在北京友谊医院核医学科就诊的37名儿童（男24名，女13名；中位年龄5.1岁；范围2.4-7.8岁）的预治疗18F-FDG PET/CT。这些患者在北京儿童医院血液科被确诊为LCH，并进行了活检。分析了包括最大标准摄取、肿瘤与正常肝脏标准摄取值比率、肿瘤与正常骨髓标准摄取值比率、代谢肿瘤体积总和（sMTV）以及所有病灶的病变总糖代谢量（sTLG）在内的5个18F-FDG PET/CT的代谢参数。患者进行了至少1年的随访，直到疾病进展/复发。进行了单变量和多变量分析，评估进展无病生存。在随访期间，有11名（29.7%）患者疾病进展/复发。单因素分析显示，危险器官受累、第5周或第11周的治疗反应、术前sMTV和sTLG与进展无病生存显著相关（P=0.024、0.018、0.006、0.006和0.042，分别）。多元Cox分析显示，第11周非反应、术前sMTV>32.55 g/cm3和sTLG>98.86 g（P=0.002、0.020、0.026，分别）是进展无病生存的危险因素。18F-FDG PET/CT的基线代谢参数可能成为预测儿童LCH预后的有希望的成像生物标志物。版权所有©2023 Quantitative Imaging in Medicine and Surgery。

Langerhans cell histiocytosis (LCH) is a rare myeloid precursor cell inflammatory neoplasia, which agonizes, maims, and even kills patients. Although clinical outcomes have steadily improved over the past decades, the progression/relapse rate of LCH remains high. The purpose of this study was to evaluate the prognostic value of the pre-treatment metabolism parameters of baseline 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F‑FDG PET/CT) in children with LCH.This cross-sectional study retrospectively and consecutively included 37 children (24 males and 13 females; median age, 5.1 years; range, 2.4-7.8 years) with pre-treatment 18F-FDG PET/CT from September 2020 to September 2022 in Nuclear Medicine Department, Beijing friendship hospital, Capital Medical University, Beijing, China. These patients were then all admitted to the hospital and diagnosed with LCH by biopsy, in Hematology Center, Beijing Children's Hospital, Capital Medical University, Beijing, China. Five metabolism parameters of 18F-FDG PET/CT were analyzed, including maximum standardized uptake, tumor-to-normal liver standard uptake value ratio, tumor-to-normal bone marrow standard uptake value ratio, sum of metabolic tumor volume (sMTV), and sum of total lesion glycolysis (sTLG) of all lesions. Patients were followed up for at least 1 year or until disease progression/relapse. Univariate and multivariate analyses of progression-free survival was performed.During follow-up, 11 (29.7%) patients had disease progression/relapse. Univariate analysis revealed that the risk organ involvement, the treatment response at the 5th or 11th week, pre-treatment sMTV, and sTLG were significantly associated with progression-free survival (P=0.024, 0.018, 0.006, 0.006, and 0.042, respectively). Multivariate COX analysis revealed that non-response at the 11th week, pre-treatment sMTV >32.55 g/cm3, and sTLG >98.86 g (P=0.002, 0.020, 0.026, respectively) were risk factors for progression-free survival.The baseline metabolism parameters of 18F-FDG PET/CT could be promising imaging biomarkers for predicting prognosis in children with LCH.2023 Quantitative Imaging in Medicine and Surgery. All rights reserved.