In this study, we aimed to investigate the demographic characteristics, treatment modalities and response rates in patients with Hairy Cell Leukemia (HCL) which have been diagnosed and followed up in our center. Data of the 27 patients diagnosed with HCL at our center between 2007 and 2018 were retrospectively evaluated. Patients diagnosed with HCL according to WHO 2016 classification of lymphoid neoplasms by bone marrow biopsy. Flow cytometry, clinical and demographic data of the patients were evaluated. BRAFV600E mutational status evaluated in selected cases. All patients were given cladribine as first line treatment. Eight of our patients (29.6%) were female and 19 (70.3%) were male. In 20 patients (74%), complete remission was detected with first-line cladribine treatment, while in 3 patients (11.1%) partial remission was achieved, and 4 patients (14.8%) were unresponsive. Rituximab was administered to 3 refractory patients while one patient received pentostatine. Two patients who could not achieve remission died due to severe and critical infection, while one patient died due to cerebrovascular disease. 24 of our patients are still alive. Cladribine confers a safe and effective treatment modality. Although purine analogs have improved response rates and progression-free survival, progress has yet to be made for resistant and relapsing patients.
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