Abstract
Introduction: The prognosis of chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) is heterogeneous. The purpose of this study was to assess factors predicting survival in patients with CLL/SLL.
Methods: Characteristics at diagnosis were collected from 2189 patients with CLL/SLL who presented to The University of Texas M. D. Anderson Cancer Center between 1985 and 2005. Univariate and multivariate analyses for survival were performed. Pretreatment parameters that remained independently significant in the multivariate analysis were used to design a model to predict an individual patient’s risk of death: the CLL/SLL score.
Results. The median age of patients was 58 years (range, 17–90 years). Overall, 1052 patients required treatment for CLL/SLL and 853 (81%) received fludarabine-based therapy. A multivariate analysis of 23 prognostic factors identified the following to have independent adverse significance for survival: 17p del and 6q del +/− other genomic aberrations (p<0.0001), age > 60 years (p<0.0001), albumin < 3.5 g/dL (p<0.0001), β2-microglobulin ≥ 2 mg/L (p<0.0001), creatinine ≥ 1.6 mg/dL (p<0.0001), hemoglobin <11 g/dL (p=0.001), presence of hepatomegaly (p=0.005), male sex (p=0.006), and absolute lymphocyte count ≥ 30 x 109/L (p=0.004). Other factors, such as IgVH mutation and CD38 or ZAP-70 expression, did not significantly correlate with survival, probably because these data were not available in enough patients and follow-up from the testing time was relatively short. The top five pretreatment parameters that remained independently significant in the multivariate analysis were used to design the CLL/SLL score in 1564 patients who had available data for all five parameters. Since the relative risks associated with each of the top five independently significant risk factors were comparable, the relative risk of death could be determined by summing the number of risk factors present at diagnosis. At 5 years, 96%, 79%, 69%, 30%, and 16% of patients with 0, 1, 2, 3, or 4 (including 1 patient with a score of 5) risk factors, respectively, are expected to be alive [insert Figure here].
Conclusions: A prognostic score to predict survival in patients with CLL/SLL is proposed. The score is based on the five most statistically significant independent factors, i.e., 17p or 6q del +/− other genomic aberrations; age; and levels of β2-microglobulin, albumin, and creatinine. This score may be used to identify specific risk groups, to improve treatment choices and to compare different therapeutic approaches in patients with CLL/SLL.
Disclosure: No relevant conflicts of interest to declare.
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