Prognostic Significance of PET/CT in Patients with Chronic Lymphocytic Leukemia (CLL) Treated with Frontline Chemoimmunotherapy

• Main Authors: Marika Porrazzo, Emanuele Nicolai, Mara Riminucci, Candida Vitale, Marta Coscia, Lorenzo De Paoli, Angela Rago, Giulia Buscicchio, Giacomo Maestrini, Silvio Ligia, Alessio Di Prima, Alessandro Corsi, Roberto Caronna, Gianluca Gaidano, Francesca Romana Mauro
• Format: Article
• Language: English
• Published: MDPI AG 2020-07-01
• Series: Cancers
• Subjects: chronic lymphocytic leukemia; PET/CT; survival
• Online Access: https://www.mdpi.com/2072-6694/12/7/1773

The role of positron emission tomography/computed tomography (PET/CT) in identifying Richter Syndrome (RS) is well established, while its impact on the survival of patients with chronic lymphocytic leukemia (CLL) has been less explored. The clinical characteristics and PET/CT data of 40 patients with a biopsy-proven CLL who required frontline chemoimmunotherapy, FCR (fludarabine, cyclophosphamide, rituximab) in 20 patients, BR (bendamustine, rituximab) in 20, were retrospectively analyzed. Standardized uptake volume (SUV_max) values ≥ 5 were observed more frequently in patients with deletion 11q (<i>p</i> = 0.006) and biopsies characterized by a rate of Ki67 positive cells ≥ 30% (<i>p</i> = 0.02). In the multivariate analysis, the presence of large and confluent PCs emerged as the only factor with a negative impact on progression-free survival (PFS), and overall survival (OS). Deletion 11q also revealed a significant and independent effect on PFS. SUV_max values ≥ 5 showed no statistical impact on PFS while in multivariate analysis, they revealed a significant adverse impact on OS (median survival probability not reached vs. 56 months; <i>p</i> = 0.002). Moreover, patients with higher SUV_max values more frequently developed Richter Syndrome (<i>p</i> = 0.015). Our results show that higher SUV_max values identify CLL patients with a pronounced rate of proliferating cells in the lymph-node compartment, inferior survival, and an increased risk of developing RS.