Indolent lymphomas are slow-growing blood cancers. These lymphomas take many years to develop and often don’t cause symptoms right away. People living with indolent lymphoma may not need to be treated for many months — or even years — after they are diagnosed. Indolent lymphomas usually can’t be cured, but treatments can often keep this disease under control for a long time. Those who are diagnosed with indolent lymphoma often have a very good prognosis and can live for many years with the disease.

What Is Indolent Lymphoma?

Lymphoma is a cancer of the immune system that develops in lymphocytes (a type of white blood cell). Lymphocytes are produced in the thymus and bone marrow. There are two main types of lymphoma: Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). Within each of these two groups are many subtypes. Different types of HL or NHL may affect different types of lymphocytes, grow and spread at different speeds, and require different treatments.

The subtypes of NHL are labeled as either indolent (slow-growing) or aggressive (fast-growing). About 4 out of 10 people with NHL have indolent lymphoma. Children with NHL are more likely to have aggressive subtypes. Indolent and aggressive lymphomas occur at similar rates in adults.

Types of indolent lymphoma include:

• Chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL)
• Cutaneous T-cell lymphoma (CTCL) or mycosis fungoides
• Follicular lymphoma (FL)
• Lymphoplasmacytic lymphoma, also known as Waldenstrom’s macroglobulinemia
• Marginal zone lymphoma

Some additional NHL subtypes fall in between indolent and aggressive. For example, mantle cell lymphoma grows faster than most indolent lymphomas but slower than most aggressive lymphomas.

Lymphoma Grade

Doctors may also use the lymphoma grade to describe how fast lymphomas grow. Grading is based on how lymphoma cells look under a microscope. Low-grade lymphomas are the same as indolent lymphomas. High-grade lymphomas are aggressive.

Signs and Symptoms of Indolent Lymphoma

Many indolent lymphomas are diagnosed before they cause any symptoms. In some cases, people may experience signs and symptoms such as:

• Fever
• Drenching night sweats
• Unexpected weight loss
• Extreme tiredness
• Enlarged lymph nodes
• Lumps on the skin

Many of these signs and symptoms can be caused by other health conditions. Experiencing any of these does not necessarily mean that you have lymphoma. However, if you are noticing any health changes that could possibly be lymphoma symptoms, it is important to talk to your doctor.

Treating Indolent Lymphoma

Doctors often use different treatment plans for indolent lymphomas and aggressive lymphomas. Aggressive lymphomas are often treated right away using multiple different chemotherapy drugs. People with aggressive subtypes may also receive immunotherapy drugs and radiation therapy.

Doctors recommend a wide range of treatments for indolent lymphoma. Some people with indolent subtypes never need treatment. Others use aggressive therapy. The treatment a person needs depends on:

• The type of NHL
• The disease stage — How far the lymphoma has spread within the body
• Prognostic factors — Factors that influence a person's outlook

Watch and Wait

Many people with indolent lymphoma use a watch-and-wait approach, also called watchful waiting or active surveillance. During watch and wait, a person does not receive any lymphoma treatments right away. Instead, they have regular visits with their health care team to monitor their lymphoma and look for any changes or new symptoms.

Avoiding treatment while living with cancer may feel uncomfortable. However, researchers have found that treating indolent lymphoma early doesn’t improve a person’s prognosis (outlook). Additionally, there are several advantages to a watch-and-wait approach:

• You can avoid side effects and complications from treatments such as chemotherapy or radiation.
• You will have more time to find a doctor you like and get to know them.
• Cancer treatments are continuously improving, so if you need treatment later, better treatment options may be available.
• You can enjoy a better quality of life.

People using a watch-and-wait approach will have many follow-up visits with their health care team. It is important to go to all of your appointments, even if you are feeling OK. During these visits, your doctor will ask you about any changes in lymphoma signs and symptoms and may run tests to look for certain signs of cancer. During this time, ask your doctor whether there are any signs and symptoms you should be watching out for. Also, inquire whether there are any lifestyle changes you can make, such as dietary changes, to keep yourself feeling well.

Your doctor may recommend beginning treatment if your symptoms have changed or if you’ve developed new ones. You may also need to start treatment if you develop certain signs of lymphoma, such as low red blood cell or platelet levels, high white blood cell levels, frequent infections, or an enlarged spleen. Some people use watch and wait for many years before needing treatment.

Radiation Therapy

Radiation treatments are often recommended for people with stage 1 or stage 2 indolent lymphoma. When lymphoma is diagnosed at these stages, it is called early-stage or limited-stage lymphoma. In early-stage lymphoma, cancer cells are found in just one or two nearby groups of lymph nodes or organs.

For people with early-stage indolent lymphoma, radiation beams are often directed at just the one small area containing cancer, rather than the whole body. Limiting radiation exposure helps limit side effects. In about half of people with early-stage indolent lymphoma, radiation treatments can cure the disease.

Chemotherapy

Chemotherapy drugs kill cells that are growing and dividing quickly. Doctors may recommend chemotherapy for people with early-stage indolent NHL who have symptoms or who can’t undergo radiation treatments. Additionally, people with advanced-stage indolent lymphoma often receive chemotherapy.

Targeted Therapy

Targeted therapy drugs recognize and block specific genes or proteins found on cancer cells. Unlike chemotherapy, targeted therapies typically leave the body’s normal cells alone, causing fewer side effects.

Rituxan (rituximab) is a targeted therapy that can be used to treat many different types of indolent B-cell lymphomas. Several other oral targeted therapies may also be recommended to treat indolent lymphoma. These drugs may be given alone, in combination with other targeted therapies, or along with chemotherapy drugs.

For some types of indolent lymphoma — such as follicular lymphoma — doctors may recommend using targeted therapy drugs as maintenance therapy. Maintenance therapy can be used for up to two years after the initial treatment is complete. Maintenance therapy can help keep cancer from growing too fast or help keep it from returning.

Chimeric Antigen Receptor T-Cell Therapy

Chimeric antigen receptor T-cell (CAR T-cell) therapy is a new treatment in which a person’s T cells (another type of white blood cell) are removed, genetically engineered to be able to recognize cancer cells, and then returned to the body. This treatment helps the immune system better fight cancer.

Yescarta (axicabtagene ciloleucel), a specific type of CAR T-cell therapy, has been approved by the U.S. Food and Drug Administration to treat follicular lymphoma that is refractory (resistant to treatment) or relapsed (came back after being treated).

Treating Relapsed or Refractory Indolent Lymphoma

Indolent lymphoma often relapses and can become increasingly resistant to treatment. If a person’s lymphoma previously went away after a particular treatment, doctors may recommend using that same treatment plan again. In other cases, doctors may recommend new drugs or different dosages.

Certain types of indolent lymphoma, such as FL and CLL/SLL, can turn into aggressive lymphomas. In this case, the lymphoma may be treated with a more aggressive treatment plan.

Talk With Others Who Understand

MyLymphomaTeam is the social network for people with lymphoma and their loved ones. On MyLymphomaTeam, more than 8,300 members come together to ask questions, give advice, and share their stories with others who understand life with lymphoma.

Are you living with indolent lymphoma? Share your experiences in the comments below, or start a conversation by posting on MyLymphomaTeam.