IBCL-188 hairy cell leukemia: A single center analysis from India

Abstract

Context: Hairy cell leukemia (HCL) is a rare chronic lymphoproliferative disorder of small mature B lymphoid cells constituting 2% of all leukemias. The published literature on HCL from the Indian sub-continent is scarce. Objective: We analyzed the clinico-demographic parameters at the time of presentation, treatment patterns, and outcomes after first-line and subsequent treatment of HCL patients at a tertiary care center in India. Design and Participants This is a retrospective analysis of 20 consecutive cases of HCL diagnosed and treated at the Department of Medical Oncology, All India Institute of Medical Sciences (AIIMS) in New Delhi between May 1, 2013, and April 30, 2023. Results: The median age at presentation was 50 years (range, 32–70 years), 15 males and 5 females. The median symptom duration was 3 months (range, 1–24 months). Common presenting symptoms were fatigue (80%), fever (40%), abdominal discomfort (20%), weight loss (20%), bleeding (15%), infection (15%), and bone pain (10%). At presentation, 18 patients (90%) had splenomegaly, 12 (60%) had hepatomegaly, and lymphadenopathy was present in 3 (15%) patients. Bicytopenia or pancytopenia was present in 90%, and bone marrow fibrosis in 75% of cases. Eighteen patients were treated with cladribine (2-CdA) with a response rate of 95% (complete remission rate, 90%). The median time for normalization of blood counts after 2-CdA was 36 days, and the median time to spleen regression was 60 days. The median follow-up period was 42 months. Three patients relapsed but attained complete remission; two received cladribine, and one received single-agent rituximab due to active infection. Minimal residual disease (MRD) was documented in three cases, and one patient received maintenance rituximab due to persistent MRD positivity. One patient died of disseminated tuberculosis during the induction phase. During follow-up, 3 patients developed pulmonary tuberculosis, and 2 had herpes zoster. Conclusion: In patients with HCL, cladribine treatment results in long-lasting disease remission, making it the treatment of choice. Tuberculosis (pulmonary/disseminated) is a major concern, especially in India, where subclinical tuberculosis rates are high.