Below is an instruction from Human. Write a response.
    ### Instruction:
    What is the outlook for Hairy Cell Leukemia ?
    ### Response:
    Certain factors affect treatment options and prognosis (chance of recovery). The treatment options may depend on the following:         - The number of hairy (leukemia) cells and healthy blood cells in the blood and bone marrow.    - Whether the spleen is swollen.
    