Clinicopathological subtypes in hairy-cell leukemia.

Thirty-six patients with hairy-cell leukemia (HCL) were evaluated, and were divided in two major subtypes: leukopenic (WBC less than 3000/microliters) and non-leukopenic (WBC greater than or equal to 3000/microliters). There were 22 leukopenic and 14 non-leukopenic patients. The leukopenic group were older than the non-leukopenic group, with an average age of 58.4 years compared with 47.6 years. The male/female ratio was higher in the leukopenic (6.3) than the non-leukopenic (2.0) patients. Splenomegaly, hepatomegaly and lymphadenopathy were found in 66%, 32%, and 18% of the leukopenic patients, compared with 92%, 57%, and 35% in the non-leukopenic patients. The leukopenic HCL was associated with more severe anemia, granulocytopenia, monocytopenia, and thrombocytopenia, and higher incidence of serious infections than the non-leukopenic HCL. Increased bone marrow reticulin fibers and unsuccessful marrow aspirations (dry taps) were more frequently associated with the leukopenic than the non-leukopenic HCL.