What is Hairy Cell Leukemia?
Hairy-cell leukemia is a rare variant of chronic leukemia, which is considered an independent nosological unit and is currently not considered as one of the clinical and morphological variants of chronic lymphocytic leukemia.
The name of hairy cell leukemia is caused by the appearance of cells specific for this type of leukemia. These cells are by origin lymphocytes, normally involved in the immune response. With leukemia, a change occurs both in their form and in function, and they cease to participate in immune reactions and develop outgrowths of the cytoplasm, which can be seen through a microscope as “torn” or “hairy” cell edges.
Hairy cell leukemia often affects the elderly and old age and develops gradually. That is why the disease often goes unnoticed and the diagnosis is made already in the later stages. The average age of diagnosis of the disease is 50 years. In 75% of cases, men are ill.
Symptoms of Hairy Cell Leukemia
A distinctive feature of the disease is a slow enlargement of the spleen, or splenomegaly, this is due to the increased destruction of pathological leukocytes in it. Splenomegaly can be manifested by heaviness in the left side of the abdomen, and during a medical examination, the elastic edge of an enlarged spleen in the left hypochondrium will be palpated. Other symptoms of hairy cell leukemia – anemia and increased susceptibility to infections – develop due to the suppression of normal blood formation in the bone marrow by leukemia cells. Symptoms associated with anemia and decreased immunity are important, but are often ignored as “age-related” manifestations in these patients. Other manifestations of the disease can be symptoms associated with general intoxication during the tumor process – weight loss and loss of appetite, inexplicably increased body temperature and night sweats. All these manifestations of the patients are more likely to be attributed to the signs of their physical aging, so it is not surprising that more often they go to the doctor not immediately.
Diagnosis of Hairy Cell Leukemia
In the diagnosis of the disease, a blood test with the detection of typical “hairy cells” comes to the fore. In addition, a blood test can reveal another typical feature of this disease, which distinguishes it from other leukemias – pancytopenia (a decrease in the number of blood cells), and not an increase in them, as with other leukemias. Anemia and a decrease in immunity in these patients are associated with pancytopenia. To confirm the diagnosis, it is also possible to carry out a puncture of the bone marrow or spleen, with subsequent histological analysis of the tissue and the detection of all the same “hairy” cells.
Treatment of Hairy Cell Leukemia
Chemotherapy is used in the treatment of hairy cell leukemia. In some cases, splenectomy is necessary for the normalization of the cellular composition of the blood and the treatment of anemia.
In the past, splenectomy was the standard approach to the treatment of cytopenia in hairy cell leukemia, the effect of which in half of the patients lasts longer than 8 months. Analogs of purines, especially cladribine, have revolutionized the treatment of this disease. The frequency of complete remissions in the treatment with cladribine exceeds 80%, complete remission is often achieved after the first course and often lasts more than 3 years. Kladribin is extremely effective in patients who have previously received pentostatin or interferon alfa.
The question of the possibility of curing hairy cell leukemia remains open, since minimal residual disease is found even in patients with prolonged clinical remission.