Hairy cell leukemia

Abstract

BACKGROUND: Historically, the first treatment choices for hairy cell leukemia (HCL) were splenectomy and alphainterferon. Recently, purine analogues (pentostatin and cladribine) changed radically the treatment modality, inducing complete and durable responses in the majority of patients. METHODS: The authors analyzed the outcome of different lines of therapy in 121 HCL patients followed in their institute from 1986 to 2008, with a median follow-up of 105 months. Patients were divided into subgroups according to the number of treatments; Group A included 121 patients who underwent a front-line therapy, Group B patients (n ¼ 53) were treated with 2 lines, Group C patients (n ¼ 34) with 3 lines, Group D patients (n ¼ 17) with 4 lines, and Group E patients (n ¼ 8) with 5 lines. RESULTS: In Group A, 92 (77%) patients obtained a complete response (CR), 23 (18%) a partial response, and the remaining 6 (5%) a minor or no response; median duration of response was 2.7 years. In Group B, 53 relapsed patients achieved a second CR rate of 73.5%; median duration of response was 2.5 years. Group C contained 34 patients in a second relapse, with a CR rate after the third line of treatment of 70.5% (median duration of response, 2.2 years). In Group D, 11 (64.7%) patients obtained a CR (median duration of response, 1.6 years), and in Group E 4 (50%) of 8 patients achieved a CR (median duration of response, 1.3 years). CONCLUSIONS: This study confirms the high risk (>40% of all patients) of retreatment of HCL patients and the need to maximize primary response. Cancer 2010;116:4788-92.

Long‐term durable remission by cladribine followed by rituximab in patients with hairy cell leukaemia: update of a phase II trial

“…This update further confirms the very high CR rate with sequential cladribine followed by rituximab for patients with HCL, including those with relapsed disease, a group with the expectation of a CR rate of around 70% using cladribine monotherapy (Else , et al 2009, Goodman , et al 2003, Zinzani , et al 2010). Responses were durable and only two patients required subsequent treatment, although the median follow-up duration of 60 months remains relatively short.…”

“…Of note, among the patients treated for first relapse, none has experienced a second relapse. The median duration of response to second line cladribine monotherapy has been reported to be around three years (Goodman , et al 2003, Zinzani , et al 2010). In the current study, none of the patients treated second line has relapsed with a median follow-up of 60 months, suggesting the superiority of the combination strategy particularly in the relapsed setting.…”

“…Re-treatment with same nucleoside analogue is also effective, but the CR rate and response duration following subsequent courses tend to be lower and shorter (Else , et al 2009, Goodman , et al 2003, Zinzani , et al 2010). As the median age at HCL diagnosis is 50–55 years, new effective strategies beyond purine analogue monotherapy are needed to extend response duration and eliminate relapse.…”

Long-term follow-up after purine analogue therapy in hairy cell leukaemia

“…In particular, longer follow-up is available, enabling the long-term assessment of outcomes after initial pentostatin or cladribine and the evaluation of these agents when used at second and subsequent lines of therapy [15], [18], [19]; the combination of a purine analogue with rituximab (MabThera, Roche Products Ltd, Hertfordshire, UK) has been evaluated for the treatment of relapsed HCL [20], [21], [22]; a number of new agents have become available for non-responders to purine analogues, or for patients requiring salvage therapy (see the chapters by Kreitmann, Zenz and Forconi in this issue); cladribine for subcutaneous administration (LITAK, Lipomed Gmbh, Weil am Rhein, Germany) has been widely introduced [23], [24]; there is a move towards improving the long-term outcome by converting a partial response (PR) to a complete response (CR) [15], [25]; and evidence-based guidelines have recently been published [25], [26], [27]. The purpose of this review is to provide an update of the available literature and of developments in our own large series.…”

Update on the Biology and Treatment Options for Hairy Cell Leukemia

“…Approximately 30-40 % of patients experience relapse after treatment with either cladribine or pentostatin, and 60-70 % of these patients can achieve a second CR or PR depending on the duration of the first CR. If relapse occurs within the first 2 years of treatment with purine analogues, then the chance of response to retreatment with the same agent decreases [77•, 108]. Because single-agent rituximab can produce CR in 10-54 % of patients with relapsed HCL [109, 110], strategies involving the combination of rituximab with purine analogues were explored.…”