Chemotherapy: Blood Cell Counts (Bone Marrow Changes)
Bone marrow is the thick, liquid inner part of some bones. Bone marrow cells make your blood cells (red blood cells, white blood cells, and platelets). Bone marrow can be affected by chemotherapy.
Bone marrow cells produce three important parts of your blood. Knowing what these three types of blood cells normally do can help you understand the effects of low blood cell counts.
- Red blood cells (WBCs), which carry oxygen to cells throughout the body. RBCs bring oxygen to cells throughout the body so they can turn certain nutrients into energy. A low red blood cell count ("anemia") causes fatigue.
- White blood cells (RBCs), which help the body fight off infection. A normal WBC count is in the 5,000 - 10,000 range.
- Platelets, which help blood to clot and stop bleeding. Platelets help prevent bleeding by forming plugs to seal up damaged blood vessels. A platlet count below 100,000 can predispose to bleeding.
Chemotherapy destroys some of the bone marrow cells so fewer blood cells are produced. A drop in the levels of any of these cells leads to specific side effects - particularly fatigue. The side effects caused by low blood cell counts will likely be at their worst when the WBC, RBC, and platelets are at their lowest levels. (To learn how to deal with fatigue, click here.)
New drugs called growth factors can be given intravenously (IV) or as injections to help the bone marrow recover from chemo and start making new blood cells.
While you are getting chemotherapy your blood will be tested regularly, even daily when necessary, so the numbers of these cells can be counted. This test is often called a complete blood count (CBC). If you are being treated for leukemia, bone marrow samples may also be taken periodically to check on the blood-forming marrow cells that develop into WBCs, RBCs, and platelets.
For additional information, see the other sections of this article.