Chronic neutrophilic leukaemia (CNL)

• What is Chronic Neutrophilic Leukaemia CNL
• Statistics on Chronic Neutrophilic Leukaemia CNL
• Risk Factors for Chronic Neutrophilic Leukaemia CNL
• Progression of Chronic Neutrophilic Leukaemia CNL
• Symptoms of Chronic Neutrophilic Leukaemia CNL
• Clinical Examination of Chronic Neutrophilic Leukaemia CNL
• How is Chronic Neutrophilic Leukaemia CNL Diagnosed?
• Prognosis of Chronic Neutrophilic Leukaemia CNL
• How is Chronic Neutrophilic Leukaemia CNL Treated?
• Chronic Neutrophilic Leukaemia CNL References

What is Chronic Neutrophilic Leukaemia CNL

Leukaemia in general, arises from cells located in the bone marrow. The bone marrow is the soft, spongy tissue located in the centre of most long bones and is responsible for the production of the cellular components of blood; namely white cells, red cells and platelets. Lymphoblasts and myeloblasts are found in the bone marrow and are normal precursor cells of white and red blood cells. These lymphoblasts are influenced by many endogenous factors such as proteins and cytokines to differentiate into mature white and red blood cells. Normally, leukaemia occurs when there is abnormal proliferation of lymphoblasts and myeloblasts in the bone marrow . It may then secondarily affect the blood, lymph nodes, liver, spleen, bones, joints, central nervous system, testes and skin.
In the case of Chronic Neutrophilic Leukaemia, this is a very rare neoplasm that has recently been recognised as a distinct entity by the World Health Organization (WHO) classification of haemopoietic malignancies. It is characterised by sustained peripheral blood neutrophilia (excess white blood cells) and is distinct because there is no evidence of dysplasia (abnormality) in any of the cell lineages and there is no associated bone marrow fibrosis.

Statistics on Chronic Neutrophilic Leukaemia CNL

CNL is a very rare disease. At 2002, there had only been 129 cases of CNL reported in literature. Chronic neutrophilic leukemia is a disease of the elderly with the mean age of diagnosis being 62 years and there seems to be a 2:1 male:female ratio.

Risk Factors for Chronic Neutrophilic Leukaemia CNL

The cause of CNL is unknown.

Progression of Chronic Neutrophilic Leukaemia CNL

CNL is characterised by the presence of large numbers of neutrophils in the peripheral blood. This can lead to further complications.

How is Chronic Neutrophilic Leukaemia CNL Diagnosed?

• General investigation of blood will reveal a consistantly elevated neutrophil count in the absence of any causative agent.
• There may be elevated serum B 12 levels, hyperuricaemia and raised alkaline phosphatase but this is not diagnostic.

Prognosis of Chronic Neutrophilic Leukaemia CNL

Overall median survival is 30 months, with a 5-year survival of 28%. Due to the lack of data on this disease it is hard to predict prognosis. The above figures are based on limited patient data. In essence, outcome can be highly variable and generally CNL is a slowly progressive disorder with survival ranging from 6 months to 20 years.

How is Chronic Neutrophilic Leukaemia CNL Treated?

Traditional chemotherapies show varying success: hydroxyurea and interferon may be useful. Allogenic (non-self donor) bone marrow transplantation represents the most promising treatment in the management of this disorder.

Chronic Neutrophilic Leukaemia CNL References

Krishnan Y, Sreedharan PS, Ramanan SG, Sagar TG. Chronic Neutrophilic Leukemia: A Case Report and Review of Literature. INDIAN JOURNAL OF MEDICAL & PAEDIATRIC ONCOLOGY. Vol. 25 No.4, 2004. [2] Souhami RL, Tannock I, Hohenberger P, Horiot JC. Oxford Textbook of Oncology. 2nd ed. Oxford University Press. 2002.