What major symptom is often associated with Hairy cell leukemia?

Hairy cell leukemia is most commonly associated with splenomegaly, which is an enlargement of the spleen. The condition is classified as a type of chronic lymphoid leukemia characterized by the accumulation of atypical lymphocytes that appear "hairy" under the microscope due to their fine projections. This malignancy often leads to a significant increase in the spleen's size because the spleen is involved in filtering blood and removing old or damaged cells. The abnormal proliferation of hairy cells can result in the spleen becoming congested and swollen.

While thrombocytopenia, hepatomegaly, and hyperuricemia can occur in certain patients with various types of leukemia or other hematologic disorders, they are not as directly linked to hairy cell leukemia specifically as splenomegaly. Thrombocytopenia may occur due to infiltration of the bone marrow, and hyperuricemia can result from rapid cell turnover or the breakdown of cells, but splenomegaly is a hallmark sign that is particularly characteristic of hairy cell leukemia.