Which treatment is typically used for hairy cell leukemia?

Hairy cell leukemia is a rare type of chronic lymphoid leukemia characterized by the proliferation of abnormal B cells that have a distinctive "hairy" appearance under the microscope. The treatment of choice for hairy cell leukemia is cladribine, which is a purine analog that leads to the death of these malignant cells.

Cladribine acts by interfering with DNA synthesis and inducing apoptosis in rapidly dividing cells, making it particularly effective in treating the neoplastic cells found in hairy cell leukemia. Studies have shown that cladribine can lead to significant clinical responses, including durable remissions, in patients with this type of leukemia.

Other treatment options mentioned, such as cyclophosphamide, rituximab, and imatinib, are not typically utilized for hairy cell leukemia. Cyclophosphamide is more commonly used in other hematologic malignancies or for immunosuppression. Rituximab, while effective for certain types of B-cell lymphomas and leukemias, is not the first-line treatment for hairy cell leukemia. Imatinib is primarily used for chronic myeloid leukemia and some other specific types of cancers, not for hairy cell leukemia.

Therefore, the standard and most effective treatment is cladribine,