Chronic leukemia is the name of a group of cancers that affect the body's hematopoietic system, as stated by the Cleveland Clinic Center for Continuing Education. These include chronic myelogenous leukemia, or CML; chronic myelomonocytic leukemia, or CMML; chronic neutrophilic leukemia, or CNL; chronic eosinophilic leukemia, or CEL; and chronic lymphocytic leukemia, or CLL.
These conditions are characterized by malignant blood cells that collect in the bone marrow, eventually leading to bone marrow failure. This can subsequently cause infection, hemorrhage and organ compromise, such as heart failure caused by anemia.
CLL is the most common form of chronic leukemia. For 2012, it was estimated that there were 16,060 new cases in western countries. Its prevalence increases with age. The incidence of CML, adjusting for age, is around 1.6 per 100,000 people a year. CMML is diagnosed at a rate of 1,100 cases a year in the United States, and only about 150 cases of CNL are reported, making it quite rare. CEL is also rare, but the actual number of cases is unknown, because patients with this condition have, in many cases, been categorized as having idiopathic hypereosinophilic syndrome.
Patients with chronic leukemia in many cases show no symptoms, and the disease is only detected during lab testing when an abnormality is found. Later, these patients may show symptoms such as anorexia, sweats, loss of weight, fever and fatigue.