Total body computed tomography scan in the initial work‐up of Binet stage A chronic lymphocytic leukemia patients: Results of the prospective, multicenter O‐CLL1‐GISL study

Abstract

Total body computed tomography (TB-CT) scan is not mandatory in the diagnostic/staging algorithm of chronic lymphocytic leukemia (CLL). The aim of this study was to determine the value and prognostic significance of TB-CT scan in early stage CLL patients. Baseline TB-CT scan was performed in 240 Binet stage A CLL patients (179 Rai low- and 61 Rai intermediate-risk) included in a prospective multicenter observational study (clinicaltrial.gov ID:NCT00917549). The cohort included 69 clinical monoclonal B lymphocytosis (cMBLs). Patients were restaged considering only radiological data. Following TB-CT scans, 20% of cases reclassified as radiologic Binet (r-Binet) stage B. r-Binet B patients showed a higher incidence of unfavorable cytogenetic abnormalities (P = 0.027), as well as a shorter PFS (P = 0.001). At multivariate analysis, r-Binet stage [HR = 2.48; P = 0.004] and IGHV mutational status [HR = 3.01; P = 0.002] retained an independent predictive value for PFS. Among 179 Rai low-risk cases, 100 were redefined as r-Rai intermediate-risk based upon TB-CT scan data, showing a higher rate of cases with higher ZAP-70 (P = 0.033) and CD38 expression (P = 0.029) and β2-microglobulin levels (P < 0.0001), as well as a shorter PFS than those with r-Rai low-risk (P = 0.008). r-Rai stage [HR = 2.78; P = 0.046] and IGHV mutational status [HR = 4.25; P = 0.009] retained a significant predictive value for PFS at multivariate analysis. Forty-two percent of cMBL patients were reclassified as r-small lymphocytic lymphomas (r-SLLs) by TB-CT scan. TB-CT scan appears to provide relevant information in early stage CLL related to the potential and the timing of patients to progress towards the more advanced disease stages.