Serum immunoglobulin levels at diagnosis have no prognostic significance in stage A chronic lymphocytic leukemia: A study of 1113 cases from the Israeli CLL Study Group

Objectives: Hypogammaglobulinemia, commonly encountered in chronic lymphocytic leukemia (CLL), is one of the main causes of morbidity and mortality; however, its prognostic significance in patients diagnosed in early stages of disease remains uncertain. The aim of this study was to evaluate the predictive power of hypogammaglobulinemia at Bonet stage A. Methods: Using the database of the Israeli CLL Study Group, we analyzed the relationship between low serum levels of IgG, IgA, and IgM; the presence of paraproteinemia, as well as other well-recognized prognostic markers in CLL; and time to first treatment (TTT) and overall survival. A total of 1113 patients consecutively diagnosed during the last 25 yrs with Binet stage A CLL were evaluated, and baseline information on serum immunoglobulin levels was found in 857 of the cases. Results: Overall survival times correlated with age >65 yr, male gender, the presence of lymphadenopathy, high serum beta 2-microglobulin (b2m), CD38 and ZAP-70 expression, but not with low levels of immunoglobulin or the presence of paraproteinemia. By univariate analysis, patients with low IgA levels had a shorter TTT; however, on multivariate analysis, the presence of lymphadenopathy (P 0.02), b2m (P 0.04), CD38 (P < 0.001), and ZAP-70 (P < 0.001) was the only laboratory parameters with prognostic significance. Conclusions: In our cohort of patients with early-stage CLL, baseline hypogammaglobulinemia and the presence of paraproteinemia were not found to correlate with prognosis.