Leukemia

Leukemia is a cancer of blood cells that starts in your bone marrow, the spongy part inside your bones that makes blood cells. When you have leukemia, your bone marrow makes too many abnormal cells, usually white blood cells, which crowd out healthy cells and prevent your blood from working properly.

In leukemia, your bone marrow produces large numbers of abnormal cells that build up in your blood and bone marrow. These abnormal cells crowd out healthy white blood cells, red blood cells, and platelets, making it harder for your body to fight infections, carry oxygen, and stop bleeding.

Acute leukemia grows quickly and usually gets worse fast, while chronic leukemia grows slowly over time. The type you have depends on which blood cell becomes cancerous and how fast it multiplies.

Abnormal leukemia cells multiply very quickly and take up space in your bone marrow and blood, pushing out healthy cells. Because there are so many abnormal cells, they use up the resources your body needs to make normal, healthy blood cells.

Your doctor will determine your specific type of leukemia based on which blood cells are affected and how fast they grow. Different types have different features and may need different treatments, so knowing your exact type helps guide your care.