Chronic lymphocytic leukemia (CLL/SLL) is a cancer of blood & bone marrow arising from white blood cells. It progresses slowly & commonly affects older adults. Many patients have no symptoms while others have enlarged lymph nodes, fatigue, fever, weight loss, night sweats & frequent infections. Usually no treatment is required in the early stage of the disease. If cancer cells are found in blood & bone marrow, it is called CLL but if the same cancer cells are found in lymph nodes, it is called SLL (Small lymphocytic lymphoma).