Hairy Cell Leukemia (HCL)

This is an uncommon adult leukemia. There are roughly 600 cases diagnosed every year in United States. It always involves the blood and bone marrow as well as lymph glands, spleen and liver. It is more commonly seen after age of 50. This disease is due to overproduction of mature lymphoid cells. The cause of this illness is unknown. It is, however, associated with a peculiar shape of the lymphoid cells that look like they have hair. It is 4 times more common in men.

Signs and Symptoms

Patients may not show any signs for many years. As the disease progresses, it can cause any of the following problems:

• Enlargement of spleen which can become massive in size

• Enlargement of Liver

• Anemia

• Low platelet count

• Low white blood cell count

• Frequent infections

• Fever

• Weight loss

• Night Sweats

Diagnosis

This diagnosis is often made when the abnormal lymphoid cells are noticed in the blood. A bone marrow test will establish the diagnosis. White blood count may be extremely low. Evaluation of blood and bone marrow under microscope will lead into the diagnosis

Treatment

Observation with no treatment: In a small group of patients having no symptoms or problems, this illness could be just monitored. 

Splenectomy: Removal of spleen used to be the only treatment until effective chemotherapy drugs were discovered in 1984. Splenectomy is still done on rare occasions when the disease becomes resistant to other treatments.

Pentostatin and Cladribine are the most effective drugs for treatment of HCL and are used as front line treatment. Interferon Alpha is another active drug. Some patients with HCL may develop an immune mediated low platelet count, which is due to destruction of platelets and not due to stage 4 disease. A bone marrow test will make this determination. Such patients are normally treated with Prednisone or IV IgG.  Other drugs that may be used in treatment of HCL are: Chlorambucil, Vincristine, Prednisone, Cytoxan and Fludarabine. Certain patients may be treated with Bone Marrow Transplantation.

Prognosis:

Most patients have excellent prognosis. The disease will remain silent for years with treatment.