SERUM LEVELS OF SOLUBLE CD23, BUT NOT SOLUBLE CD25, PREDICT DISEASE PROGRESSION IN EARLY-STAGE B-CELL CHRONIC LYMPHOCYTIC-LEUKEMIA

Serum levels of the soluble forms of CD23 (sCD23) and CD25 (sCD25) wer e prospectively analyzed with respect to their prognostic relevance in early stage B-cell chronic lymphocytic leukemia (B-CLL). SCD23 and sC D25 levels were determined in 105 patients with newly diagnosed B-CLL (Binet stage A). In 93 of the patients, these levels were correlated w ith other already established indicators for risk of disease progressi on, including the histologic pattern of bone marrow infiltration, lymp hocyte doubling time (LDT), and the serum level of thymidine kinase (T K). High serum levels of both sCD23 and of sCD25 were associated with a diffuse bone marrow infiltration, a LDT less than or equal to 12 mon ths, and elevated (> 5 U/L) serum TK, respectively. Moreover, examinat ion of the clinical course of 76 untreated patients showed that high l evels of sCD23, but not of sCD25, at initial diagnosis were linked wit h disease progression. Furthermore, in a stepwise Cox regression model , high levels of sCD23 and a short LDT were shown to be strong predict ors of progressive disease within the first year of disease presentati on. Therefore, it appears to be justified to incorporate sCD23 levels into the risk profile of early stage B-CLL and to take them into accou nt for stratification in risk-adapted treatment strategies.