Hairy cell leukemia is an extremely rare blood cancer. Between 500 and 800 cases of this disease are reported to the National Cancer Institute in the United States every year.
The median age at diagnosis is 55.
Hairy cell leukemia affects a person's B-lymphocytes; a mutation turns them cancerous and they begin to build up in the liver, the bone marrow, and the spleen. Unlike similar diseases, they do not build up in the lymph nodes.
The name 'hairy cell leukemia' is derived from the fact that, under the microscope, these cells have very small, thin projections on them.
There are three primary types of treatment options available for people diagnosed with hairy cell leukemia:
Sometimes, patients with this disease are put on 'watch and wait.' This means that the patient and his or her doctor monitor the patient's health frequently for signs that the cancer is progressing. This method can be psychologically excruciating for some patients, but it does prevent unnecessary treatment in patients who otherwise feel fine and are not symptomatic.
In the treatment of hairy cell leukemia, the first-line treatment of choice is chemotherapy, and it comes in the form of a single chemotherapy drug, cladribine (marketed under the brand name Leustatin). This drug is administered intravenously for seven days.
Sometimes, in cases of relapsed disease, chemotherapy may take the form of penostatin (Nipent) or rituximab (Rituxan).
Before chemotherapy became the front-line treatment of hairy cell leukemia, the front-line treatment was the removal of the patient's spleen, a procedure called a splenectomy.
This form of treatment is not as common as it once was, although it still may be performed if the patient does not respond to chemotherapy.
If untreated, hairy cell leukemia can cause very serious blood disorders, including anemia, neutropenia, and thrombocytopenia..