A medical diagnosis that includes the word "indolent" may not be a bad thing. It can mean a "lazy" condition that is slow-moving. That is often the case with indolent lymphomas. Sometimes watchful waiting is all they require in the early stages of the disease. Researchers are working hard to find better treatments for these conditions.
What Are Lymphomas?
Most people know about blood and the circulatory system. Sometimes we forget that we have another circulatory system, the lymphatic system. This system moves a colorless liquid called lymph through our bodies. It removes waste and acts as part of the immune system.
Lymphocytes are white blood cells that are part of the lymphatic system. Lymphoma occurs when these cells become cancerous. Like leukemias, lymphomas are blood cancers. In leukemia, cancerous cells occur in the bone marrow and bloodstream. In lymphoma, they are found mostly in lymph nodes and organs.
There are two types of lymphomas: Hodgkin (HL) and non-Hodgkin (NHL). Non-Hodgkin is much more common. Experts sometimes classify non-Hodgkin lymphomas as either aggressive or indolent. They also classify them according to the type of white blood cell they affect, whether B cells or T cells. The B cell type is more common.
Children can also get non-Hodgkin lymphoma, but they get different types. The treatment of childhood non-Hodgkin lymphoma is different from treatment for the adult types. Over 80% of children and teenagers who get childhood NHL are cured.
Symptoms of Non-Hodgkin Lymphoma
Symptoms are the same for non-Hodgkin lymphomas, whether aggressive or indolent. The difference lies in how quickly the disease progresses.
Often, enlarged lymph nodes are the first symptom. Swollen nodes can appear in the neck, underarm, and groin and are usually painless. Enlarged nodes may also occur deeper in the body. When located internally, they can press on organs and cause a variety of symptoms.
Lymphomas can also appear first in the bloodstream or bone marrow, where they can cause a shortage of certain blood cells:
- A shortage of red blood cells causes anemia.
- Too few white blood cells can keep the body from fighting off infections.
- Too few platelets can cause abnormal bleeding and bruising.
Symptoms like night sweats, fever, and weight loss are usually signs of aggressive disease, not indolent.
Diagnosis of Lymphoma
Biopsy is the usual way of diagnosing lymphoma. Doctors try to get enough tissue to learn which type of lymphoma is present. There are many subtypes of lymphoma that call for varying treatments.
Doctors may order other tests to help with the diagnosis, including:
When Is Indolent Lymphoma Treated?
Doctors often delay treating indolent lymphomas. Early treatment may not have any advantages. Watchful waiting spares those with indolent lymphomas from the side effects of treatment.
When treatment becomes necessary, indolent lymphomas usually respond well. Often, the disease goes into remission. Doctors don't consider indolent lymphomas curable, but those with this type of disease can survive for many years. Those with aggressive lymphomas often receive intensive treatment and sometimes are cured.
Types of Treatment
The treatment of non-Hodgkin lymphoma depends upon many factors, including the subtype of the disease. Commonly used treatments include:
- Radiation therapy
- Targeted drug therapy such as monoclonal antibodies
- Immunotherapy (drugs that stimulate the body to attack the cancer)
- Bone marrow or stem cell transplants
Scientists are also developing two new types of treatment.
CAR T cell therapy. Researchers remove T cells from the blood of a person with lymphoma. In the lab, they attach substances called chimeric antigen receptors (CARs) to the T cells. They put the cells back into the blood, where they attack the lymphoma.
Vaccines. Unlike other vaccines, those for lymphoma are given to people who already have the disease. People with early disease or those in remission may be candidates for a vaccine. The goal is to create an immune reaction.
Who Gets Indolent Lymphomas?
No one knows what causes non-Hodgkin lymphomas. There are some known risk factors, but these vary according to the type of lymphoma. The most common indolent lymphoma, follicular lymphoma, has these risk factors:
- A history of taking drugs that suppress the immune system
- Infection with certain viruses
- Exposure to chemicals that kill weeds and insects
- Lifestyle factors such as smoking
Age is a risk factor for all non-Hodgkin lymphomas, which are most common from ages 65 to 74.