18F-FDG PET/MR Assessment of Pediatric Langerhans Cell Histiocytosis

Abstract

Introduction Langerhans cell histiocytosis (LCH) is a histiocytic proliferative disease without a well-understood etiology. The aim of our study is to summarize the imaging features of PET/MR in children with LCH and to explore its diagnostic role in LCH. Methods Retrospective analysis was performed of the pretreatment PET/MR imaging data of 15 children with LCH. Comparison of ADC values was done between lesions and normal tissues. Results Of the fifteen patients enrolled, five had single-organ or single-system involvement, and ten had multiple-system involvement. Nine patients had varying degrees of bone destruction and increased FDG uptake, whereas thickening and deviation of the pituitary stalk and disappearance of the normal high-signal intensity of T1WI in the neurohypophysis were observed in the pituitary gland in six of them. Splenomegaly with diffuse increased FDG uptake or a normal spleen with increased FDG uptake was found in four cases, liver in three, multiple lymph node enlargement in three, pulmonary lesions in three, and increased metabolism in medullary cavity in two cases. Additionally, two cases involved the skin. Hypermetabolic nodules were detected in muscle in one case, thyroid involvement in one case, and a mediastinal lesion in one case. Conclusion PET/MR can show well the distribution of the organs, systems, and lesions involved in LCH and is of considerable significance in the systemic evaluation of LCH.

Quantitative Analysis of TP53-Related Lung Cancer Based on Radiomics

“…In addition, radiomics has also been applied to the study of other diseases, such as Langerhans cell histiocytosis. 32 …”

“…In addition, radiomics has also been applied to the study of other diseases, such as Langerhans cell histiocytosis. 32 However, there are still several limitations in our study. Firstly, the sample size of this study is relatively small.…”

Comparison of the different imaging modalities used to image pediatric oncology patients: A COG diagnostic imaging committee/SPR oncology committee white paper

“…84,95 There are currently a limited number of these systems in dedicated pediatric hospitals, but there is early literature validating the PET imaging with either PET/CT or PET/MRI to be essentially interchangeable for clinical usage. 68,69,[72][73][74]96,97 One difference between adult and pediatric PET imaging is the recommendation to perform true whole-body imaging, that is, vertex-to-toes rather than "eyes-to-thighs" imaging, as pediatric cancer can often occur anywhere in the body, including brain and distal extremities, more so than in adults.…”

Clinical Perspectives for 18F-FDG PET Imaging in Pediatric Oncology: Μetabolic Tumor Volume and Radiomics

“…However, the 18 F-FDG PET scan, instead of a bone scan, which should not be considered for evaluating multisite bone disease, is considered the most accurate tool for detecting bone and soft-tissue lesions (multisystem LCH) and it is strongly recommended during initial staging [ 156 , 157 ]. Most importantly, by evaluating disease metabolic activity, the 18 F-FDG PET scan is the most accurate tool for evaluating front-line response to treatment and further decision making in the case of a multisite/multisystem disease [ 159 , 160 ]. The MTV/TLG metabolic parameters may have a role in better risk stratification of multisystem LCH but, to our knowledge, there is no relevant published data probably because of the disease’s rarity both in children and especially in adults, and the poor prognosis of young children in the case of multisystem disease with risk organ involvement.…”