Domenico Albano1, Luca Camoni2, Carlo Rodella3, Raffaele Giubbini2, Francesco Bertagna2. 1. Nuclear Medicine, University of Brescia and Spedali Civili Brescia, Brescia, Italy. Electronic address: doalba87@libero.it. 2. Nuclear Medicine, University of Brescia and Spedali Civili Brescia, Brescia, Italy. 3. Health Physics Department, ASST-Spedali Civili, Brescia, Italy.
Abstract
INTRODUCTION: Chronic lymphocytic leukemia (CLL) is an indolent, low-grade B-cell lymphoproliferative disorder, which may evolve into aggressive lymphoma, a phenomenon called Richter syndrome (RS). Our aim was to study the accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (2-[18F]-FDG PET/CT) and its semiquantitative parameters for the detection of RS and the impact on overall survival (OS). MATERIALS AND METHODS: Eighty patients with histologically proven CLL were retrospectively included. PET/CT images were qualitatively and semiquantitatively examined by estimating the maximum standardized uptake value body weight (SUVbw), lean body mass (SUVlbm), body surface area (SUVbsa), lesion-to-blood-pool SUV ratio (L-BP SUV R), lesion-to-liver SUV ratio (L-L SUV R), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) and comparing them with the main clinical-histologic variables. OS curves were plotted according to the Kaplan-Meier method. RESULTS: Seventy-eight patients had positive 2-[18F]-FDG PET/CT, whereas the remaining 2 were not FDG-avid. All PET/CT metabolic parameters were significantly higher in the RS group compared with the no-RS group, except for MTV and TLG. The best thresholds identified were 9 for SUVbw, 5.3 for SUVlbm, 1.7 for SUVbsa, 2 for L-L SUV R, and 4.8 for L-BP SUV R. After a median follow-up of 32 months, 24 patients died; OS was significantly shorter in patients with RS than patients without RS (16.5 vs. 27.8 months; P = .001). Binet-stage, B symptoms, SUVbw, SUVlbm, SUVbsa, L-L SUV R, and L-BP SUV R were shown to be independent prognostic features. CONCLUSIONS: Semiquantitative PET/CT parameters that are SUV-related may be useful in discriminating patients with a high risk of developing RS and also for predicting OS.
INTRODUCTION: Chronic lymphocytic leukemia (CLL) is an indolent, low-grade B-cell lymphoproliferative disorder, which may evolve into aggressive lymphoma, a phenomenon called Richter syndrome (RS). Our aim was to study the accuracy of 2-deoxy-2-[18F]fluoro-D-glucose positron emission tomography/computed tomography (2-[18F]-FDG PET/CT) and its semiquantitative parameters for the detection of RS and the impact on overall survival (OS). MATERIALS AND METHODS: Eighty patients with histologically proven CLL were retrospectively included. PET/CT images were qualitatively and semiquantitatively examined by estimating the maximum standardized uptake value body weight (SUVbw), lean body mass (SUVlbm), body surface area (SUVbsa), lesion-to-blood-pool SUV ratio (L-BP SUV R), lesion-to-liver SUV ratio (L-L SUV R), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) and comparing them with the main clinical-histologic variables. OS curves were plotted according to the Kaplan-Meier method. RESULTS: Seventy-eight patients had positive 2-[18F]-FDG PET/CT, whereas the remaining 2 were not FDG-avid. All PET/CT metabolic parameters were significantly higher in the RS group compared with the no-RS group, except for MTV and TLG. The best thresholds identified were 9 for SUVbw, 5.3 for SUVlbm, 1.7 for SUVbsa, 2 for L-L SUV R, and 4.8 for L-BP SUV R. After a median follow-up of 32 months, 24 patients died; OS was significantly shorter in patients with RS than patients without RS (16.5 vs. 27.8 months; P = .001). Binet-stage, B symptoms, SUVbw, SUVlbm, SUVbsa, L-L SUV R, and L-BP SUV R were shown to be independent prognostic features. CONCLUSIONS: Semiquantitative PET/CT parameters that are SUV-related may be useful in discriminating patients with a high risk of developing RS and also for predicting OS.