Hairy cell leukemia: survival and relapse

Since its initial description approximately 50 years ago, there has been an impressive evolution in therapies for hairy cell leukemia. Long-term follow-up with 2-cholorodeoxyadenosine and 2′-deoxycoformycin demonstrates that both agents result in a high complete remission rate and overall survival. Relapse rates appear to be between 20% and 30%. Therapeutic strategies for patients with relapsed disease include retreatment with a purine analog, rituximab, or the anti-CD22 pseudomonas exotoxin A immunoconjugate, BL-22.