Combined Treatment with Splenectomy and Cladribine in Hairy Cell Leukemia in Taiwan: A Clinicopathologic Study of 5 Cases

BACKGROUND: Hairy cell leukemia (HCL) is a rare B-cell lymphoid malignancy that is characterized by the presence of hairy cells in the peripheral blood and bone marrow, pancytopenia and various degrees of splenomegaly. Very few reports have explored the clinicopathologic features and treatment outcome of HCL in Taiwan. METHODS: Of 33 patients with malignant lymphoma who underwent splenectomy over a 10-year period (1996-2005), 5 cases of HCL were retrospectively studied. RESULTS: All cases presented with various degrees of splenomegaly. Pancytopenia was noted in 3 cases, and lymphadenopathy in 1. Typical hairy cells with positive tartrate-resistant acid phosphatase stain were noted in 2 cases. Only 3 cases could be diagnosed with HCL based solely on bone marrow findings. In contrast, all spleen specimens had characteristic pathologic features. All patients underwent splenectomy uneventfully, and cladribine was given at a median time of 2 months after splenectomy without significant side effects. Complete remission with durable response was documented in 4 patients (80%) with a median follow-up of 29 months (range, 4-96 months). The last patient experienced partial remission but was only followed up for 4 months. CONCLUSION: For the HCL patients in this study, splenectomy had a role not only in improving cytopenia but in aiding diagnosis. Cladribine is safe and highly effective for Taiwanese patients and should be considered as first-line treatment for HCL.