Value of 18F-FDG PET/CT in the staging, interim therapeutic and prognostic evaluation of mucosa-associated lymphoid tissue lymphoma / 中华核医学与分子影像杂志

ABSTRACT

Objective To assess the value of 18F-fluorodeoxyglucose (FDG) PET/CT in the staging,interim therapeutic and prognostic evaluation of mucosa-associated lymphoid tissue (MALT) lymphoma.Methods Thirty-six MALT lymphoma patients (20 males,16 females;average age61.7 years) confirmed by pathology from January 2008 to January 2018 were retrospectively analyzed.18F-FDG PET/CT were performed before chemotherapy and radiotherapy for staging.The detective sensitivity was evaluated.The staging results of gastric MALT lymphoma and extragastric MALT lymphoma by PET/CT were compared with Fisher exact probability method.PET/CT was performed in 17 of 36 patients after 4 courses of chemotherapy,and 17 patients were divided into positive group (≥≥4) and negative group (＜4) according to scores of Deauville 5-point scale.The progression-free survival (PFS) was evaluated using Kaplan-Meier survival analysis.Results FDG-positive lesions were found in 31 of 36 patients with the sensitivity of 86.1％ (31/36).The results of PET/CT were negative in stage Ⅰ patients.In stage]Ⅱ-Ⅳ patients,the results of 18F-FDG PET/CT combined with bone marrow biopsy were in accordance with the results of clinical staging.The accuracy of PET/CT in staging of gastric MALT lymphoma patients was 9/17,which was significantly lower than that of extragastric MALT lymphoma patients (17/19;P=0.025).The PFS of negative group evaluated by interim PET/CT was longer than that of positive group (x2 =4.16,P＜0.05).The 2-year PFS rates of the 2 groups were (85.7± 13.2)％ and (27.8 ±21.3)％,respectively.The PFS of patients with low expression of Ki-67 was significantly longer than that of patients with high Ki-67 expression (x2=4.22,P＜0.05).Conclusions In stage]Ⅱ-Ⅳ MALT patients,18F-FDG PET/CT combined with bone marrow biopsy can improve the staging accuracy.The staging accuracy of PET/CT in extragastric MALT lymphoma is significantly higher than that of gastric MALT lymphoma.PET/CT and Ki-67 can provide effective information on the prognostic evaluation for patients with MALT lymphoma.