Interim FDG18-PET SUVmax Variation Adds Prognostic Value to Deauville 5-Point Scale in the Identification of Patients with Ultra-High-Risk Diffuse Large B Cell Lymphoma
Sara Duarte, Adriana Roque, Tiago Saraiva, Carolina Afonso, Bárbara Marques, Carla Barros Lima, Dulcelena Neves, Ana Lai, Gracinda Costa, Augusta Cipriano, Catarina Geraldes, L. Ruzickova, José Pedro Carda, Marília Gomes
Abstract
Introduction Interim response evaluation by 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (iPET) in diffuse large B cell lymphoma (DLBCL) could be important to rule out disease progression and has been suggested to be predictive of survival. However, treatment guidance by iPET is not yet recommended for DLBCL in clinical practice. We aimed to compare the predictive value of iPET when utilizing the visual Deauville 5-point scale (DS) and the semiquantitative variation of maximum standardized uptake value (ΔSUV max ). Materials and Methods We included 85 patients diagnosed with DLBCL and uniformly treated with standard protocols. iPET with DS of 1-3 and/or ΔSUV max ≥66% was defined as negative. Univariable and multivariable Cox regression analyses were performed to determine the independent factors affecting progression free survival (PFS) or overall survival (OS) and to estimate PFS and OS. Results iPET positivity, measured by DS or ΔSUV max , showed predictive value of disease refractoriness, improved by combining DS and ΔSUV max . After a median follow-up of 50.1 months, iPET was an independent predictor for both PFS and OS when interpreted by DS, but only for PFS by ΔSUV max . Combined visual and semiquantitative analysis (D4-5 & ΔSUV max <66%) was an independent predictor of PFS and OS, and allowed to identify an ultra-high-risk subgroup of patients with very dismal outcome, increasing the discriminating capacity for iPET. Conclusion Our study suggests that combined DS and ΔSUV max in iPET assessment predicts refractory disease and distinguishes ultra-high-risk DLBCL patients with a very dismal prognosis, who may benefit from PET-guided therapy adjustment.