Hairy cell leukemia: A decade long experience of North Indian Hematology Center

Abstract

Introduction:Hairy cell leukemia is a rare chronic B-cell disorder that follows an indolent but progressive course. This disorder is characterized by pancytopenia, splenomegaly, bone marrow fibrosis and the presence of atypical lymphoid cells with hairy projections in peripheral blood, bone marrow and spleen. Treatment is mainly with nucleoside analog cladribine, which induces complete remission in up to 85% cases.Materials and Methods:This is a retrospective analysis of Hairy cell Leukemia cases diagnosed and treated in the Department of Hematology, All India Institute of Medical Sciences, New Delhi between 2002 and 2013. Various parameters such as clinical features, laboratory parameters including complete blood cell count, bone marrow findings, cytochemistry, immunophenotyping by flowcytometry or immunohistochemistry, treatment protocol and complications secondary to treatment and relapse were reviewed.Results:A total of 35 cases were diagnosed during this period of 12 years of which 27 received cladribine and went in to remission. Median follow-up duration was 26 months. 5 (18%) cases had a relapse and all relapsed cases achieved second remission with cladribine; however, there was no case of second malignancy in our cohort.Conclusion:Cladribine has emerged as the treatment of choice for hairy cell leukemia given that the overwhelming majority of patients achieve long-lasting complete remissions. Upon relapse, these patients could be successfully salvaged with cladribine retreatment.

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

“… [37] focused on 88 younger cladribine-treated patients from the Scripps Clinic, aged ≤40 years, and reported 100% ORR and 88% CR. In the other three cladribine series [40] , [41] , [42] the ORR and CR rates were in line with those from countries with a more established history of purine analogue treatment. In India, 27 of 35 patients diagnosed with HCL received cladribine, while 8 did not, due to financial constraints [41] .…”

“…In the other three cladribine series [40] , [41] , [42] the ORR and CR rates were in line with those from countries with a more established history of purine analogue treatment. In India, 27 of 35 patients diagnosed with HCL received cladribine, while 8 did not, due to financial constraints [41] . In two institutions in Mexico the CR rate with cladribine was 100%; however, only 11/29 patients were able to obtain cladribine and the remainder received interferon [42] .…”

“…The recent studies with short median follow-up (2–5 years) reported relapses in 17%–27% (Table 1) [39], [40], [41], [42]. The Turkish study reported a median time to relapse of 36 months after a CR versus 6 months after a PR [40].…”

“…These results have been confirmed by recent studies, all retrospective (Table 1), including long-term data from three earlier series: from the Scripps Clinic [37], from Bologna [18], and our own series, updated in 2009 [19], and reviewed in 2011 with a focus on the implications for clinical practice [15]. There are also two series, from Spain and France, with some minor overlap of patients from previous reports [38], [39] and three new reports from Turkey, India and Mexico [40], [41], [42]. Four of these studies report results with both cladribine and pentostatin, while the other four report only cladribine.…”

“…Similarly, in the Spanish series 8 patients in PR were treated with a second cycle of cladribine, which led to a CR in 6 patients (75%) [38] . In the Indian series 2 patients received a second cycle of treatment at 6–8 months and both achieved a CR [41] .…”