Value of 18F-FDG PET/CT in the interim therapeutic and prognostic evaluation of primary gastrointestinal lymphoma / 中华核医学与分子影像杂志

ABSTRACT

Objective:To assess the value of 18F-FDG PET/CT imaging and relevant factors in the interim therapeutic and prognostic evaluation of primary gastrointestinal lymphoma (PGIL) patients. Methods:From January 2008 to January 2018, 41 patients with B-cell PGIL (24 males, 17 females; age: 26-84 years) confirmed by pathology in Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine were retrospectively included. 18F-FDG PET/CT was performed before chemotherapy and radiotherapy and after 3-4 courses of chemotherapy. There were 17 cases of mucosa-associated lymphoid tissue (MALT) lymphoma and 24 cases of diffuse large B-cell lymphoma (DLBCL). Mann-Whitney U test was used to compare the differences of metabolic parameters (SUV max, metabolic tumor volume (MTV), total lesion glycolysis (TLG)) before treatment between MALT lymphoma and DLBCL patients. ROC curve analysis was used to analyze the predictive abilities of different parameters for progression-free survival (PFS), and Cox regression analysis was used to analyze the influencing factors for PFS. Results:The median follow-up time of 41 patients was 25 (6-84) months, with the 3-year PFS rate of 55.9% and the overall survival (OS) rate of 80.2%. The baseline SUV max (23.2±11.9), MTV (260.7(66.2, 740.7) cm 3) and TLG (1 902.9(592.2, 8 418.1) g) in DLBCL were significantly higher than those in MALT lymphoma (7.9(6.2, 9.8), 45.9(28.4, 104.2) cm 3, 121.1(72.8, 295.6) g; z values: -4.02, -3.10, -3.92, all P<0.05). ΔSUV max in DLBCL patients (AUC=0.80, P=0.012), ΔSUV max% (AUC=0.89, P=0.007; AUC=0.80, P=0.012), ΔMTV%(AUC=0.91, P=0.005; AUC=0.77, P=0.026) and ΔTLG% (AUC=0.87, P=0.011; AUC=0.77, P=0.026) in MALT lymphoma and DLBCL patients before and after treatment were predictive factors of PFS. Multivariate analysis showed that ΔSUV max% was an independent factor for PFS of MALT lymphoma (hazard ratio ( HR)=17.192, 95% CI: 2.035-145.245, P=0.009), while ΔMTV% and ΔTLG% were factors for PFS of DLBCL (both HR=7.556, 95% CI: 1.968-29.016, P=0.003). Conclusions:There are significant differences in metabolic parameters between MALT lymphoma and DLBCL before treatment. Interim PET/CT is effective for the prediction of prognosis of MALT lymphoma and DLBCL.