Clinical characteristics and outcome of young chronic lymphocytic leukemiapatients: A single institution study of 204 cases

A retrospective analysis on chronic lymphocytic leukemia (CLL) patients les s than or equal to 55 years observed at a single institution was performed with the purpose of characterizing the clinical features and outcome of you ng CLL and of identifying patients with different prognostic features. Over the period from 1984 to 1994, 1,011 CLL patients (204 [20%] less than or e qual to 55 years of age and 807 [80%] >55 years of age) were observed. At d iagnosis, younger and older patients displayed a similar distribution of cl inical features, except for a significantly higher male/female ratio in you nger patients (2.85 v 1.29; P < .0001). Both groups showed an elevated rate of second primary cancers (8.3% v 10.7%), whereas the occurrence of Richte r's syndrome was significantly higher in younger patients (5.9% v 1.2%; P < .00001). Younger and older patients showed a similar overall median surviv al probability (10 years) but were characterized by a different distributio n of causes of deaths: CLL unrelated deaths and second primary malignancies predominated in the older age group, whereas the direct effects of leukemi a were prevalent in the younger age group. Although younger and older patie nts displayed a similar survival, the evaluation of the relative survival r ates showed that the disease had a greater adverse effect on the expected s urvival probability of the younger population. Multivariate analysis showed that for young CLL patients only dynamic parameters, such as lymphocyte do ubling time and other signs of active disease, were the independent factors that significantly influenced survival probability (P = .00001). A prolong ed clinico-hematologic follow-up allowed us to identify two subsets of youn g CLL patients with a different prognostic outcome: a group of patients (40 %) with long-lasting stable disease without treatment and an actuarial surv ival probability of 94% at 12 years from diagnosis and another group (60%) with progressive disease and a median survival probability of 5 years after therapy. For the latter patients, the therapeutic effect of innovative the rapies with curative intents needs to be investigated in prospective, compa rative clinical trials. (C) 1999 by The American Society of Hematology.