Chronic lymphocytic leukemia (CLL)

Chronic lymphocytic leukemia (CLL) is a type of cancer that causes the body to produce large numbers of mature white blood cells (lymphocytes). It is sometimes referred to as chronic lymphoblastic leukemia.

CLL occurs more frequently in adults in their 60s. It is more common in men and is rarely seen in children.

Symptoms of CLL include weakness and fatigue, fever, night sweats, poor appetite, and weight loss. The spleen and lymph glands may become swollen and painful. Because the immune system doesn't work as well as it should, people with CLL may be more likely to get infections.

Treatment for CLL usually includes chemotherapy. Although long-term response to treatment is common, complete cure is rare. But researchers are studying aggressive treatment combinations and bone marrow transplants.

In some cases, CLL does not need to be treated when it is in an early stage. Instead, it is watched carefully for signs of change. This is called watchful waiting.