Survival trends among 1,325 patients with chronic lymphocytic leukemia seen over the past 40 years in Israel

Abstract

In the light of recent data showing survival improvement of patients with chronic lymphocytic leukemia (CLL), we investigated clinical characteristics and survival patterns of patients with CLL over the last 40 years in Israel. Demographic and clinical data collected in the database of the Israeli CLL Study Group were analyzed. Of the 1,325 patients, 221 were diagnosed during the time period 1968-1989, 456 during 1990-1999, and 639 during 2000-2010. There was shift toward older age (median, 71 vs. 68 vs. 66 years) and a higher proportion of patients at Binet stage A at diagnosis (77.6% vs. 66.7% vs. 60.3%) in the more recent time periods. Median survival for the entire cohort was 10.9 years; 12.2 years for patients diagnosed at Binet stage A, 8.5 years for stage B, and 6.4 years for stage C patients. Older age, high-beta 2-microglobulin level, and expression of ZAP-70 predicted shorter survival. There were no apparent changes over time regarding gender, age or different clinical stages. Young patients with Binet stage A had lower life expectancy than the general population; but, in older ages, the survival rates were comparable. There were increased proportions of CLL patients diagnosed in early stages, and, at older age, during the last decades, however, survival rates according to sex, age, or stage remained stable. CLL continues to be an incurable disease affecting survival even in patients diagnosed at early stages. Survival benefit shown in recent trials using chemoimmunotherapy has still to be proven in wider general practice.