A splenectomy is the procedure done to remove the spleen. Before effective drugs became available for hairy cell leukemia, splenectomy was the first-line treatment for the disease.

Your spleen is an organ located in the upper left portion of your abdomen. It contains groups of lymph nodes, and its main function is to filter old and worn-out cells from the blood. When your spleen becomes enlarged, not only can it cause discomfort, but it can sometimes lower your blood cells to dangerous levels. If your spleen is removed, other organs like the lymph nodes and the liver can perform most of its functions, although you'll be at higher risk of infection.

Occasionally, splenectomy may be required for patients with very large spleens who haven't responded to or who relapse after treatment with cladribine (Leustatin®), penostatin (Nipent®), rituximab (Rituxan®) and BL22.