A type of cancer of the blood and bone marrow.

Chronic lymphocytic leukemia is slow growing. It develops from a group of white blood cells called lymphocytes. It usually happens in older adults.

There may be no symptoms at first. Symptoms may include swollen lymph nodes, feeling very tired, fever and belly pain caused by an enlarged spleen.

Treatment may not be needed right away. Treatments may include chemotherapy, targeted medicines and immunotherapy. Another option may be a bone marrow transplant, also called a stem cell transplant.