Chronic Lymphocytic Leukemia: Evaluation of Cytogenetic Markers as Prognostic Factors

Abstract 4860

Backgroud: Chronic lymphocytic leukemia (CLL) is one of the most frequent chronic lymphoproliferative disorders in Europe. It is characterized by persistent monoclonal lymphocitosis with localized or generalized lymphadenopathy. Despite the initial clinical presentation, it has a heterogeneous natural history, with the majority of patients living 10–12 years, but with some patients dying rapidly, within 2–3 years of diagnosis. Beside clinical prognostic factors, novel cytogenetic markers are recognized to be useful in predicting disease free and overall survival in CLL.

AIMS: In a retrospective study throughout 10 years (1999-2009), we analyzed the clinical and biological presentation and compared the evolution and survival of patients with B-CLL using different cytogenetic markers.

METHODS: We identified 112 cases (63 males and 49 females) of B-CLL with cytogenetic study by fluorescence in situ hybridization (FISH).

RESULTS: Amongst 112 patients, the male to female (M/F) ratio was 1.3:1 and the median age was 70 (43-96) years. At diagnosis, the median lymphocyte count was 15.5 G/L (5.4-173). Fifty five patients (49%) had lymphadenopathies and seventeen (15%) had splenomegaly and/or hepatomegaly at presentation. By the revised Rai staging system seventy (63%) patients were included in low risk group, thirty (27%) in intermediate risk group and twelve (10%) in high risk group. The expression of ZAP-70 and CD38 by flow citometry was performed in 75 patients and revealed 13 (17%) patients CD38+ and 12 (16%) ZAP70+. The study of chromosomal aberrations with FISH showed thirty six patients (32%) with no abnormality, thirty six (32%) with isolated 13q deletion, fifteen (14%) with 12 trisomy, twelve (11%) with 11q deletion and thirteen (11%) with 17p deletion. Forty (36%) patients showed progressive disease in a median time of sixteen months (0-120), thirteen with 13qdel, seven with 17pdel and five with 12 trisomy. After treatment two patients showed progressive disease, six maintain a stable disease and thirty two obtain a remission, nine in complete remission. The Overall Survival (OS) at ten years was 70%. By the revised Rai staging system the OS at ten years was 80% for low risk, 70% for intermediate risk and all the high risk patients died during follow up. The OS at five years for the del13q-, 12 trisomy, del11q- and del17p- was 90%, 88%, 58% and 60%, respectively.

SUMMARY: Chronic lymphocytic leukemia is currently considered a chronic disorder with a favourable outcome, but with a variable evolution to progressive disease. This retrospective study allowed the characterization of patient with CLL in our department and the acknowledgement that our results are quite similar to the published data.