18F-FDG uptake of the non-tumour-specific sites on the PET/CT examinations of onco-haematological paediatric patients
Jorgov Linda
KÁROLY RÁCZ CONSERVATIVE MEDICINE PROGRAM
Dr. Reusz György
SE Szemészeti Klinika, Tanterem
2025-05-29 14:00:00
Clinical Haematology
Dr. Masszi Tamás
Dr. Györke Tamás
Dr. Erdélyi Dániel János
Dr. Garai Ildikó
Dr. Kovács Gábor
Dr. Marton Nikolett
Fehérné Dr. Radácsi Andrea
The detection of non-tumour-specific Fluorodeoxyglucose (FDG) uptake by structures that are not invaded by malignant tissue on the positron emission tomography/computed tomography (PET/CT) images has been reported for a long time, and is considered as a potential pitfall. This thesis aimed to elucidate the possible importance of FDG uptake by focusing on paediatric patients with onco-haematological diseases. Diffuse and intense FDG uptake could provide additional information that reflects the metabolic status of the patient, thereby aiding treatment management, which is a major objective in this specific patient population.
A pilot study and a validation study were conducted to analyse the frequency and intensity of diffuse FDG uptake by selected organs (thymus, bone marrow, liver, spleen, and spinal cord) and the prevalence of brown adipose tissue (BAT) activation on baseline (bPET) and interim examination (iPET). Studies focusing on BAT activation were also presented. We aimed to evaluate the correlation between FDG uptake of these non-tumour-specific sites, the metabolic response of the tumour tissue, and evolution of the disease with treatment.
Diffuse and intense FDG uptake is frequently observed at sites without tumour invasion in children with Hodgkin lymphoma (HL) prior to treatment. However, the prevalence of this observation is frequently reduced after two cycles of chemotherapy. In contrast, the FDG uptake by the normal liver tissue is frequently enhanced. Inadequate response may be connected to the lack of increase in the liver FDG uptake after two cycles of chemotherapy, FDG uptake by the lymphoma on baseline PET, and FDG uptake of the spinal cord or spleen without tumour invasion on iPET.
It could be a further perspective to continue the evaluation of the value of the non-tumour-specific FDG uptake in the prediction of progression-free survival (PFS) by reaching a longer clinical follow-up in a larger patient group. Comparing the behaviour of such non-tumour-specific FDG uptake among different types of paediatric onco-haematological populations is another objective that arose in this thesis.
