Clinical investigation of 145 cases of chronic lymphocytic leukemia in Japan

CLL is the most common leukemia in Europe and America, representing 30% of all forms of leukemia. In contrast, in Japan, the incidence is only 3%. This is the largest multicenter study in Japan to evaluate the relationship between outcome in CLL patients and the data obtained during patient's first visits. The data obtained during first visits of 145 patients with chronic lymphocytic leukemia (CLL) that were made between 1982 and 1991 and their outcomes were analyzed and compared with those of patients with CLL diagnosed in terms of Rai and Binet staging in Europe and America. In our patients, the male-to-female ratio was 1.8, and the mean age at onset was 63.2+/-11.7 (+/-SD) years. The crude 5-year survival rate was 42.4% in men and 44.9% in women. Patients with B-CLL with surface IgM phenotype had better outcomes than those with B-CLL with surface IgG (P<0.1); patients with surface IgM/IgD phenotypes and those with T-CLL had the poorest outcomes (B-CLL with surface IgM vs. B-CLL with surface IgM/IgD T-CLL, P<0.05). When these patients were re-evaluated in terms of Binet and Rai staging, generalized Wilcoxon analysis revealed no differences between the survival curves of different stage groups, as seen in patients with CLL in Europe and America. Patients whose CLL developed during their fifties or earlier had the most favorable outcomes (P<0.05); the later the onset of disease, the worse the outcome. CLL was associated with hypogammaglobulinemia (30%) and autoimmune hemolytic anemia (7.6%), and 4 patients (2.8%) died of secondary cancer. Outcomes of our patients were compared with those of patients with CLL in Europe and America.