Characteristics of primary mediastinal large B-cell lymphoma in 18F-FDG PET/CT imaging / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the characteristics of primary mediastinal large B-cell lymphoma (PMBL) in 18F-fluorodeoxyglucose (FDG) PET/CT imaging.Methods From July 2010 to April 2019,18F-FDG PET/CT images of 27 patients (10 males,17 females,median age 31 (19-57) years)with pathologically confirmed PMBL from the First Affiliated Hospital of Nanjing Medical University were retrospectively analyzed.The location,shape,density,presence of necrosis and calcification,and invasion around or beyond the lesions were observed.The maximum standardized uptake value (SUVmax),metabolictumor volume (MTV) and total lesion glycolysis (TLG) were measured by automatic segmentation algorithm method.Spearman correlation analysis was used to evaluate the correlation between SUVmax or MTV or TLG and the maximum diameter or Ann Arbor staging.Results The lesions appeared as anterior mediastinal huge masses in 27 patients,and grew in the anterior mediastinal cross-regionally in 25 patients,lobulated at the edge in 24 patients.Low-density necrosis lesions were found in 18 patients.The lesions were surrounded by large blood vessels in 15 patients and tracheae were compressed in 12 patients.Lung tissues were invaded in 3 patients,abdominal lymph nodes and bone marrow were invaded in 1 patient,and no splenomegaly was found in 27 patients.The maximum diameter,SUVmax,MTV and TLG were (11.6±3.7) cm,21.07(15.78,25.09),190.43 (130.14,350.75) cm3 and 2165.54 (1465.86,4185.21) g,respectively.There was no correlation between SUVmax and the maximum diameter of lesions (rs =-0.305,P =0.122),while MTV and TLG were positively correlated with the maximum diameter (rs values0.741,0.532,both P＜0.05).The maximum diameter,MTV and TLG were positively correlated with Ann Arbor staging (rs values0.394,0.413,0.422,all P＜0.05),while SUVmax was not (rs=0.031,P＞0.05).Conclusions PMBL mostly presents as large anterior mediastinal mass with the high 18F-FDG uptake in 18F-FDG PET/CT imaging,and the focal necrosis is common,while abdominal lymph nodes,spleen and bone marrow invasion are rare.MTV and TLG of lesions positively correlate with Ann Arbor staging.