High levels of CD 20 expression predict good prognosis in chronic lymphocytic leukemia

Heterogeneity of CD 20 expression exists in chronic lymphocytic leukemia ( CLL ), therefore, we explored the prognostic significance of CD 20 expression in Chinese patients with CLL . Multiparameter flow cytometry was used to detect the expression of CD 20 in CD 5 + CD 19 + cells. In 172 CLL patients, the median expression percent of CD 20 was 97.82% (range, 0–100), and the median mean fluorescence intensity ( MFI ) of CD 20 in CLL cells was 731.45 (range, 0.00–9071.90). The percentage of CD 20 + cells in the patient group with mutated variable region of immunoglobulin genes ( IGHV ) was higher than in the non‐mutant IGHV group (mean, 92.1% vs 80.4%, P  < 0.001). There were no differences in the MFI of CD 20 + cells in all prognostic factor groups. Representation of the data using a receiver operating characteristic plot reflected separation between the two IGHV groups, with an area under the curve of 0.661 (95% confidence interval, 0.569–0.753). At the cut‐off value of 60.3% for percentage of CD 20, the sensitivity and specificity were 90.00% and 38.46%, respectively. Patients whose percentage of CD 20 antigen was above 60.3% had longer treatment‐free survival (hazard ratio, 0.452; 95% confidence interval, 0.232–0.884, P  = 0.020). Percentage and MFI of CD 20 were the variables not associated with treatment‐free survival by multivariate Cox regression analysis ( P  < 0.05). High level of CD 20 expression in de novo CLL appears to be associated with a good prognosis.