Note: Some citations in the text of this section are followed by a level of evidence. The PDQ editorial boards use a formal ranking system to help the reader judge the strength of evidence linked to the reported results of a therapeutic strategy. (Refer to the PDQ summary on Levels of Evidence for more information.)
Cladribine (2-chlorodeoxyadenosine, 2-CdA) and pentostatin are both highly efficacious in the treatment of patients with disease refractory to interferon-alpha.[1,2,3,4] Patients who relapse after the first course of cladribine or pentostatin often respond well to retreatment with the same or another purine analog.[5,6,7,8,9,10] Rituximab can induce durable complete remissions with minimal toxic effects in patients with multiple relapsing or refractory disease after purine analog therapy or after interferon.[11,12,13,14][Level of evidence: 3iiiDiv] The lack of subsequent immunosuppression with rituximab has made this treatment a common choice among relapsing patients in the absence of a clinical trial. Combinations of rituximab with either cladribine or pentostatin are effective in achieving complete remission and are under clinical evaluation.[10,15,16] Both anti-CD25 and anti-CD22 recombinant immunotoxins under clinical evaluation can induce complete remissions in patients whose disease is resistant to retreatment with purine analogs or rituximab.[17,18]
Mistletoe has been used for centuries for its medicinal properties. Reviewed in [1,2,3,4,5,6] It was reportedly used by the Druids and the ancient Greeks, and it appears in legend and folklore as a panacea. It has been used in various forms to treat cancer, epilepsy, infertility, menopausal symptoms, nervous tension, asthma, hypertension, headache, and dermatitis. Modern interest in mistletoe as an anticancer treatment began in the 1920s. Reports of more than 30 clinical studies of mistletoe as...
Trials (including the ongoing NCT00923013, NCT00321555, and CAT-80151001 studies, and NCI-04-C-0014, which is now completed) are in the process of, or have, evaluated new therapies for this group of patients.
Aggressive, high-dose chemotherapy has been beneficial in some cases, but the associated morbidity and mortality are high. It should not be considered unless other, more frequently effective therapies have been exhausted.
Current Clinical Trials
Check for U.S. clinical trials from NCI's list of cancer clinical trials that are now accepting patients with refractory hairy cell leukemia. The list of clinical trials can be further narrowed by location, drug, intervention, and other criteria.
General information about clinical trials is also available from the NCI Web site.
Piro LD, Carrera CJ, Carson DA, et al.: Lasting remissions in hairy-cell leukemia induced by a single infusion of 2-chlorodeoxyadenosine. N Engl J Med 322 (16): 1117-21, 1990.
Tallman MS, Hakimian D, Variakojis D, et al.: A single cycle of 2-chlorodeoxyadenosine results in complete remission in the majority of patients with hairy cell leukemia. Blood 80 (9): 2203-9, 1992.
Saven A, Burian C, Koziol JA, et al.: Long-term follow-up of patients with hairy cell leukemia after cladribine treatment. Blood 92 (6): 1918-26, 1998.
Grever M, Kopecky K, Foucar MK, et al.: Randomized comparison of pentostatin versus interferon alfa-2a in previously untreated patients with hairy cell leukemia: an intergroup study. J Clin Oncol 13 (4): 974-82, 1995.
Hoffman MA, Janson D, Rose E, et al.: Treatment of hairy-cell leukemia with cladribine: response, toxicity, and long-term follow-up. J Clin Oncol 15 (3): 1138-42, 1997.
Goodman GR, Burian C, Koziol JA, et al.: Extended follow-up of patients with hairy cell leukemia after treatment with cladribine. J Clin Oncol 21 (5): 891-6, 2003.
Ribeiro P, Bouaffia F, Peaud PY, et al.: Long term outcome of patients with hairy cell leukemia treated with pentostatin. Cancer 85 (1): 65-71, 1999.
Zinzani PL, Magagnoli M, Bendandi M, et al.: Long-term follow-up of hairy cell leukemia patients treated with 2-chlorodeoxyadenosine. Haematologica 85 (9): 922-5, 2000.
Gidron A, Tallman MS: 2-CdA in the treatment of hairy cell leukemia: a review of long-term follow-up. Leuk Lymphoma 47 (11): 2301-7, 2006.
Else M, Dearden CE, Matutes E, et al.: 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 145 (6): 733-40, 2009.
Hagberg H, Lundholm L: Rituximab, a chimaeric anti-CD20 monoclonal antibody, in the treatment of hairy cell leukaemia. Br J Haematol 115 (3): 609-11, 2001.
Lauria F, Lenoci M, Annino L, et al.: Efficacy of anti-CD20 monoclonal antibodies (Mabthera) in patients with progressed hairy cell leukemia. Haematologica 86 (10): 1046-50, 2001.
Thomas DA, O'Brien S, Bueso-Ramos C, et al.: Rituximab in relapsed or refractory hairy cell leukemia. Blood 102 (12): 3906-11, 2003.
Angelopoulou MK, Pangalis GA, Sachanas S, et al.: Outcome and toxicity in relapsed hairy cell leukemia patients treated with rituximab. Leuk Lymphoma 49 (9): 1817-20, 2008.
Ravandi F, Jorgensen JL, O'Brien SM, et al.: Eradication of minimal residual disease in hairy cell leukemia. Blood 107 (12): 4658-62, 2006.
Else M, Osuji N, Forconi F, et al.: The role of rituximab in combination with pentostatin or cladribine for the treatment of recurrent/refractory hairy cell leukemia. Cancer 110 (10): 2240-7, 2007.
Kreitman RJ, Wilson WH, White JD, et al.: Phase I trial of recombinant immunotoxin anti-Tac(Fv)-PE38 (LMB-2) in patients with hematologic malignancies. J Clin Oncol 18 (8): 1622-36, 2000.
Kreitman RJ, Stetler-Stevenson M, Margulies I, et al.: Phase II trial of recombinant immunotoxin RFB4(dsFv)-PE38 (BL22) in patients with hairy cell leukemia. J Clin Oncol 27 (18): 2983-90, 2009.