Hematologic cancers encompass a wide variety of cancers of the blood system, including leukemia, Hodgkin's lymphoma, Non-Hodgkin's lymphoma, and multiple myeloma.
Leukemia is a group of cancers that affects the blood and the bone marrow, the soft tissue inside the bone where blood cells are formed. Leukemia leads to an uncontrolled increase in the number of immature white blood cells or blasts. Over time, these cancerous blast cells fill up the bone marrow and prevent healthy red cells, platelets and mature white cells from being produced.
According to the American Cancer Society, about 44,600 new cases of leukemia will be diagnosed this year. Leukemia is divided into two major types: acute, which grows rapidly, and chronic, which progresses more slowly. Among these, the four most common types of leukemia include acute lymphocytic leukemia (ALL), acute myelogenous leukemia (AML), chronic lympocytic leukemia (CLL), and chronic myelogenous leukemia (CML).
Lymphomas are cancers of the lymph glands and lymphatic system, and the two main types are Hodgkin's lymphoma and non-Hodgkin's lymphoma. According to the Leukemia and Lymphoma Society, about 628,000 people are currently living with lymphoma or are in remission.
The American Cancer Society estimates that there will be about 8,830 new cases of Hodgkin's lymphoma this year. This type of lymphoma can occur in both children and adults and is one of the most curable forms of cancer. Hodgkin's lymphoma commonly affects lymph nodes in the neck or in the area between the lungs behind the breastbone. It can also begin in groups of lymph nodes under the arms, in the abdomen, or in the groin.
Non-Hodgkin's lymphoma is more common. According to the American Cancer Society, about 66,360 Americans will be diagnosed with non-Hodgkin's lymphoma this year, and more than 95% of the cases occur in adults. Non-Hodgkin's lymphoma refers to a variety of cancers involving the lymph system and can begin in any part of the body, not just the lymph nodes.
Multiple myeloma is a cancer of the plasma cells in the bone marrow. When these plasma cells grow out of control and form bone tumors, they can cause pain and destruction of the bones, and make it more difficult for the bone marrow to make red blood cells, white blood cells and platelets. Multiple myeloma mainly affects older adults, and the American Cancer Society estimates that about 20,520 new cases will be diagnosed in the US this year.