Complications

Hairy cell leukemia progresses very slowly and sometimes remains stable for many years. For this reason, few complications of the disease occur.

Untreated hairy cell leukemia that progresses may crowd out healthy blood cells in the bone marrow, leading to serious complications, such as:

• Infections. Reduced numbers of healthy white blood cells put you at risk of infections that your body might otherwise fight off.
• Bleeding. Low platelet counts make it hard for your body to stop bleeding once it starts. If you have a mildly low platelet count, you might notice that you bruise more easily. Very low platelet counts can cause spontaneous bleeding from the nose or gums.
• Anemia. A low red blood cell count means fewer cells are available to carry oxygen throughout your body. This is called anemia. Anemia causes fatigue.

Increased risk of second cancers

Some studies have found that people with hairy cell leukemia may have an increased risk of developing a second type of cancer. It isn't clear whether this risk is due to hairy cell leukemia's effect on the body or if the risk comes from the medications used to treat hairy cell leukemia.

Second cancers found in people treated for hairy cell leukemia include non-Hodgkin's lymphoma, among others.