New therapeutic aspects of hairy cell leukemia

Chronic B cell proliferation: An estimated 80 to 120 new cases of hairy cel l leukemia are diagnosed annually in France. Median survival is 5 years for untreated patients who develop a series of infectious complications. For m any years, interferon alpha was the standard therapy but the therapeutic st rategy has changed with the arrival of purine analogs, deoxycoformicine and 2-CdA. Therapeutic options: We searched Medline, Pascal, and Current Contents for literature on the treatment of hairy cell leukemia over the last 10 years a nd discuss here available data on response rate, mechanism of action and ad verse effects of different therapeutic options. By treatment: Interferon generally induces partial response and most patien ts relapse after treatment withdrawal. The purine analogs, desoxycoformycin e and 2-chlorodeoxyadenosine, are more active than interferon inducing resp onse in approximately 90% of the cases, even after interferon failure; comp lete response is achieved in 50% to 70% of patients. Relapse rate at 5 year s appears to be limited to 10% (n) over tilde 15%. Besides infections, the main adverse effect is the constant deep and persistent decline in CD4 coun ts but with no special risk of opportunistic infection. The increased rate of secondary cancers in long-term survivors and its possible relationship w ith treatments remains a controversial topic.