Long-term Follow-Up of 233 Patients With Hairy Cell Leukaemia, Treated Initially With Pentostatin or Cladribine, at a Median of 16 Years From Diagnosis

Br J Haematol. 2009 Jun;145(6):733-40. doi: 10.1111/j.1365-2141.2009.07668.x. Epub 2009 Mar 29.


Hairy cell leukaemia (HCL) was first described 50 years ago. Median survival was then 4 years. The purine analogues, introduced in the 1980s, transformed this prognosis. We reviewed data retrospectively from 233 patients, treated with pentostatin (n = 188) or cladribine (n = 45), to investigate the current long-term outlook. Median follow-up was 16 years. There were no significant differences in outcome between the two agents. Overall, the complete response (CR) rate was 80% and median relapse-free survival was 16 years. After relapse (n = 79) or non-response (n = 5), 26 patients received pentostatin and 58 cladribine; 69% achieved CR and median relapse-free survival was 11 years. After third-line therapy (n = 23), 50% achieved CR and median relapse-free survival was 6.5 years. However, CRs were equally durable, whether after first, second or third-line therapy. Complete responders and those with both haemoglobin >100 g/l and platelet count >100 x 10(9)/l before treatment had the longest relapse-free survival (P < 0.0001). Patients still in CR at 5 years had only a 25% risk of relapse by 15 years. Outcomes for patients with recurrent disease improved with the monoclonal antibody rituximab, combined with either purine analogue. Overall only eight patients died of HCL-related causes. Patients achieving a CR can expect a normal lifespan.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antibodies, Monoclonal / administration & dosage
  • Antibodies, Monoclonal, Murine-Derived
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use*
  • Cladribine / administration & dosage
  • Female
  • Follow-Up Studies
  • Humans
  • Kaplan-Meier Estimate
  • Leukemia, Hairy Cell / drug therapy*
  • Leukemia, Hairy Cell / mortality
  • Male
  • Middle Aged
  • Pentostatin / administration & dosage
  • Recurrence
  • Remission Induction
  • Rituximab
  • Survival Rate
  • Treatment Outcome


  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Murine-Derived
  • Pentostatin
  • Cladribine
  • Rituximab