Objective: To investigate the curative effect of
hairy cell leukemia by clatabine. Methods: The clinical data of 24 patients with
hairy cell leukemia treated by
cladribine from November 2006 to October 2017 were analyzed retrospectively, then the curative effect and
adverse drug reaction were analyzed. Results: ① A total of 24 patients including 22 male and 2 female, and the median age was 49.5 years (range 33 to 76) at diagnosis. There were 20 patients with of
splenomegaly (4 patients with mild
splenomegaly, 4 moderate
splenomegaly, and 12 massive
splenomegaly), 3 patients with enlargement of lymph nodes, and 1 patients who had undergone
splenectomy. Five patients were
pancytopenia, 15 were
cytopenia in 2 lineages, and 4 patients were
cytopenia only in one lineage. The median ratio of HCL cells detected by flow cytometry in bone marrow was 21.79% (0.69%-68.96%). BRAF mutation was detected in 15 patients by first generation or next generation sequencing technology. ② Among 24 patients, 20 were treated with
cladribine alone (one course in 19 patients, 2 courses in 1 patient), and 4 patients were treated with
cladribine combined with
rituximab (one course in 3 patients, 2 courses in 1 patient). Excepting 5 patients whose follow-up time was not reaching 6 months, 19 patients were evaluated for efficacy in 6-12 months
after treatment: 9 patients obtained CR, 9 obtained unconfirmed CR (Cru), the other 1 obtained PR, the CR/CRu rate was 94.7%, the overall response rate (ORR) was 100.0%. ③ All the 24 patients appeared 2-4 grade hematological adverse reactions after
cladribine treatment, which were mainly grade 3/4
neutropenia (66.67%) and grade 3/4
thrombocytopenia (29.2%). All the adverse reactions were controlled or recovered spontaneously. ④ After the median follow-up time of 15 (3-133) months, no progression, recurrence or death occurred in the patients. Both median OS and PFS were not reached. Conclusion: This study suggests that treatment of HCL with
cladribine has high response rate, controllable adverse reactions and the good prognosis.