Blood cancers such as leukemia and lymphoma can affect nearly every part of the body and be especially complicated to understand and treat. The Leukemia and Lymphoma Society, an organization dedicated to fighting these cancers, estimates that someone is diagnosed with blood cancer every three minutes in the United States.
While blood cancers come in many forms, understanding them is integral to awareness and prevention.
Main types of blood cancer
There are two main types of blood cancer — leukemia and lymphoma — with multiple variations under the umbrella of each. While both affect the white blood cells, leukemia often originates in the bone marrow, and lymphoma usually originates in the lymphatic system. However, some leukemia can begin in the lymph nodes, and some lymphomas can affect bone marrow.
Because of the different types, there are many treatment methods. “Some lymphomas and chronic leukemia can be observed and monitored for years without ever requiring treatment. Others require immediate and aggressive treatment,” said Ann Wierman, MD, FACP, Section Chief of Hematology Oncology at MountainView Hospital.
“Bone marrow is the factory that makes all of our blood cells. Red blood cells carry oxygen, white blood cells fight infection and platelets keep us from bruising and bleeding,” Wierman said. Leukemia occurs when a group of malignant bone marrow cells overproduce, creating a large number of abnormal blood cells.
Chronic lymphocytic leukemia (CLL) is a leukemia that affects the white blood cells produced in the bone marrow. These leukemia cells often grow slowly and may not cause any symptoms for a couple of years or more. Usually, slow-moving CLL does not require treatment but in rare cases, CLL can move more quickly and require chemotherapy. CLL most often occurs in older adults.
Acute myeloid leukemia (AML) and acute lymphocytic leukemia (ALL) also begin in the bone marrow but move to the bloodstream much more quickly than chronic leukemia. These types of leukemia can be fatal within months if not treated immediately. “AML and ALL always require immediate chemotherapy. Laboratory tests can predict if regular chemotherapy will be able to cure acute leukemia, or if it will require a bone marrow transplant as well,” Wierman said. AML is common in adults and ALL, while it can occur in adults, is most commonly found in children.
Lymphoma starts in the lymph nodes of the lymphatic system. “The body has tiny lymph nodes all over, from our scalp to our legs, that are part of the immune system. Normally, these lymph nodes are too tiny to feel unless they become enlarged because of inflammation, infection or tumor,” Wierman said.
The two main types of lymphoma are Hodgkin’s lymphoma, also called Hodgkin’s disease, and non-Hodgkin’s lymphoma.
Like leukemia, not all lymphomas require immediate treatment or treatment at all. When lymphoma does require treatment, it is often chemotherapy, radiation and/or surgery. “Many times, we only treat lymphoma when it causes symptoms,” Wierman said.
Non-Hodgkin’s lymphoma is the most common type of lymphoma. In some cases it starts in the lymphatic system, and in other cases it begins with an abnormal production of white blood cells, similar to myeloid leukemia. While non-Hodgkin’s lymphoma is often treated with chemotherapy, the chemotherapy drugs used for it are different than those used to treat Hodgkin’s lymphoma.
Hodgkin’s lymphoma occurs with a cancerous growth on or in the lymph nodes. When the cancer is detected early, treatment can be limited to radiation or surgery and may not require chemotherapy unless the cancer cells have spread. “While Hodgkin’s lymphoma is rare, patients with the disease may be more prone to develop other cancers years later, so they must be closely followed for the rest of their life,” Wierman said.
Symptoms of blood cancer
For some patients, symptoms can appear suddenly and require immediate evaluation and intervention. For other patients, symptoms can be subtle and develop over several years.
Symptoms can include:
- Compromised immune system, which can make patients more prone to infection, shingles and fever blisters
- Anemia, easy bruising and bleeding
- Unexplained and unintended weight loss
- Swollen glands (lymph nodes) or enlarged spleen
- Drenching sweats, especially during the nighttime