What are Indolent Lymphomas and How Are They Treated?

Medically Reviewed By: Eric D. Jacobsen, MD

Indolent lymphomas are types of non-Hodgkin lymphoma (NHL) that grow and spread slowly. They account for about 40% of all NHL cases in the United States and generally arise later in life.

Treatment for indolent lymphomas depends on a variety of factors, including the type and stage of the disease (how far it has advanced). Sometimes indolent lymphomas can be monitored and do not require immediate treatment. Treatment approaches can often bring remissions. While there is a potential for relapse, researchers are working to develop better therapies.

What are the signs and symptoms of indolent lymphoma?

Indolent lymphomas tend to have few signs or symptoms. When symptoms do occur, they can include:

  • Swollen lymph nodes
  • Fever not caused by another illness
  • Unintended weight loss
  • Severe night sweats
  • Severe fatigue that doesn’t diminish with rest
  • Painless or painful lumps on the skin

Having these symptoms does not always mean that you have lymphoma, but it is advised to bring any changes in your body to the attention of a medical professional.

What are the types of indolent lymphoma?

Cutaneous T-cell lymphoma (CTCL)

A group of lymphomas that form primarily in the skin and may spread to the lymph nodes, blood, and other organs. It originates in T cells, immune system cells that play a central role in defending against disease. The most common type of CTCL is mycosis fungoides, which primarily involves the skin. Sézary syndrome is a type of CTCL that circulates in the blood and causes very red skin.

Follicular lymphoma (FL)

The second most common type of NHL, follicular lymphoma grows very slowly and is marked by the formation of clumps of B cells (white blood cells that produce antibodies) in lymph nodes.

Lymphoplasmacytic lymphoma and Waldenström’s macroglobulinemia

These originate in blood-forming cells in the bone marrow, causing a slowdown in the production of normal blood cells. The result can be anemia and a weakened immune system. In patients with Waldenström’s, the abnormal B cells overproduce an immunoglobulin protein called IgM that thickens the blood.

Marginal zone lymphoma (MZL)

The third most common indolent NHL, MZL develops in B cells at the edge of lymph tissue, a regional called the marginal zone. It is sometimes associated with chronic infectious or autoimmune diseases.

Small cell lymphocytic lymphoma (SLL)

Both SLL and chronic lymphocytic leukemia (CLL) are slow-growing B cell cancers. The difference between them is the location of the cancer cells. In SLL they’re located mainly in the lymph nodes; in CLL they’re mostly in the blood and bone marrow.

What are the treatment options for indolent lymphoma?

Treatment for indolent lymphomas depends on a variety of factors, including the type and stage of the disease (how far it has advanced), its prognosis, and the patient’s age and other medical conditions. Another important consideration is whether the patient is being treated for the disease for first time or whether they have relapsed after previous treatment.

For patients diagnosed in the early stages of slow-growing lymphomas, one option is to “watch and wait” — to have the disease closely monitored but not treated until symptoms appear or change. For more advanced cases, treatment can consist of radiation therapy, chemotherapy, and/or targeted therapy in a variety of combinations. Some patients may undergo a stem cell transplant.

While these approaches can often bring remissions, the potential for relapse has spurred researchers to work to develop better therapies. A recent advance is CAR T-cell therapies, which use specially modified versions of a patient’s T cells to generate a potent immune system attack on lymphoma cells.

In a national clinical trial led by Dana-Farber’s Caron Jacobson, MD, MMSc, a CAR T-cell therapy called axi-cel drove cancer cells to undetectable levels in nearly 80% of patients with follicular lymphoma or marginal zone lymphoma who had already undergone multiple previous treatments. The therapy was approved by the U.S. Food and Drug Administration in March 2021 for patients with relapsed/refractory follicular lymphoma.

About the Medical Reviewer

Eric D. Jacobsen, MD

Dr. Jacobsen received his MD from the University of Connecticut School of Medicine in 1999. He completed postgraduate training in Internal Medicine at Johns Hopkins Hospital, followed by a fellowship in Medical Oncology and Hematology at Dana-Farber Cancer Institute. He joined the division of Hematologic Malignancies in 2005.