Follicular lymphoma is a slow-growing cancer that affects the lymphatic system, and while treatment cannot always cure the disease, modern therapies are helping people live longer and better lives, managing symptoms and extending periods of remission.

Managing a slow-growing cancer: what patients need to know about treatment goals

When follicular lymphoma returns after previous treatment, the situation is called recurrent disease. This happens because follicular lymphoma is typically a chronic condition rather than one that can be permanently eliminated. The main goals of treating recurrent follicular lymphoma are to control symptoms, slow the progression of the disease, and improve quality of life for as long as possible. Treatment decisions depend heavily on how advanced the disease is, how long it has been since the last treatment, what symptoms the patient is experiencing, and the person’s overall health and ability to tolerate therapy.^[1][9]

Doctors use both standard treatments that have been approved by medical societies and newer experimental therapies being tested in clinical trials. Because follicular lymphoma often behaves unpredictably, with some patients experiencing rapid disease return and others enjoying years of remission, treatment plans must be highly individualized. About 20 percent of patients develop disease progression within the first two years after initial chemotherapy, and these individuals often have a poorer outlook, with a five-year survival rate of approximately 50 percent. However, many others live for decades with this condition, experiencing multiple treatment cycles followed by periods of disease control.^[9]

The disease is graded from 1 to 3 based on how the cancer cells look under a microscope. Grades 1, 2, and 3A are considered low-grade or slow-growing forms, while grade 3B grows more quickly and is treated more aggressively. Understanding the grade helps doctors predict how the lymphoma might behave and which treatments are most appropriate.^[6][12]

Standard treatment approaches for recurrent follicular lymphoma

The backbone of standard treatment for recurrent follicular lymphoma includes several well-established approaches. Radiation therapy is often used when the disease is localized to one or a few areas. This treatment uses high-energy rays to kill cancer cells in specific locations. For early-stage recurrent disease (Stage I), radiation therapy can send the cancer into long-term remission in about half of patients. The treatment is typically delivered over several sessions, and side effects depend on which part of the body is treated but may include fatigue and skin changes in the treated area.^[1][10]

Monoclonal antibody therapy is a cornerstone of treatment for this disease. The most commonly used drug is rituximab, which targets a protein called CD20 found on the surface of B cells, the type of lymphocyte affected by follicular lymphoma. Rituximab helps the immune system recognize and destroy cancer cells. It can be used alone or combined with chemotherapy drugs to increase effectiveness. Patients typically receive this therapy through an intravenous infusion, and treatment cycles can continue for months or even years. Side effects may include infusion reactions such as fever, chills, or rash during the first few treatments, but these usually become less severe with subsequent doses.^[1][11]

Chemotherapy remains an important treatment option, particularly when the disease is more widespread or aggressive. Several chemotherapy regimens are used, often combining multiple drugs. Common combinations include bendamustine with rituximab, or regimens known as R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) and R-CVP (rituximab, cyclophosphamide, vincristine, and prednisone). These combinations work by attacking cancer cells in different ways, making it harder for the disease to resist treatment. Chemotherapy is typically given in cycles, with treatment periods followed by rest periods to allow the body to recover. The duration of treatment varies but often lasts several months.^[9][11]

Side effects of chemotherapy can be significant and depend on which drugs are used. Common side effects include fatigue, nausea and vomiting, hair loss, increased risk of infections due to low white blood cell counts, anemia causing tiredness and breathlessness, and easy bruising or bleeding due to low platelet counts. Most side effects are temporary and resolve after treatment ends, but some, such as fatigue, may persist for months. Doctors can prescribe medications to help manage many of these side effects and improve quality of life during treatment.^[9]

For patients who have had multiple relapses or whose disease does not respond to standard treatments, more intensive options may be considered. Hematopoietic stem cell transplantation, also called bone marrow transplant, involves giving high doses of chemotherapy to destroy cancer cells, followed by infusion of healthy stem cells to rebuild the blood and immune system. These stem cells can come from the patient themselves (autologous transplant) or from a donor (allogeneic transplant). Transplantation is a complex procedure with significant risks, including infection, organ damage, and in the case of donor transplants, graft-versus-host disease where the donor cells attack the patient’s tissues. However, it can lead to long-lasting remission in some patients.^[8]

CAR T-cell therapy is a newer form of immunotherapy that has been approved for certain patients with relapsed follicular lymphoma. In this treatment, a patient’s own T cells (another type of white blood cell) are collected, genetically modified in a laboratory to recognize and attack lymphoma cells, and then infused back into the patient. The modified cells can multiply in the body and continue fighting cancer for months or years. CAR T-cell therapy can cause serious side effects, including cytokine release syndrome (a severe inflammatory reaction causing high fever, low blood pressure, and breathing difficulties) and neurological problems such as confusion or seizures. Despite these risks, this therapy has shown remarkable results in some patients whose disease did not respond to other treatments.^[8][10]

Promising therapies being tested in clinical trials

Clinical trials are research studies that test new treatments to determine if they are safe and effective. For follicular lymphoma, numerous clinical trials are underway testing innovative approaches that may offer hope when standard treatments are no longer working. These trials are conducted in phases, each with a specific purpose. Phase I trials primarily test safety and determine the appropriate dose of a new drug. Phase II trials evaluate whether the treatment is effective against the disease and continue to monitor safety. Phase III trials compare the new treatment with current standard therapy to see if it offers advantages.^[9]

One promising area of research involves targeted therapies that attack specific molecular pathways involved in follicular lymphoma. Most cases of follicular lymphoma have a genetic change called the t(14;18) translocation, which leads to overproduction of a protein called BCL-2 that helps cancer cells survive. Drugs called BCL-2 inhibitors block this protein, causing cancer cells to die. Several BCL-2 inhibitors are being studied in clinical trials for relapsed follicular lymphoma. These drugs work differently from chemotherapy and may cause different side effects, including low blood cell counts and tumor lysis syndrome, a condition where dying cancer cells release their contents into the bloodstream too quickly.^[2][9]

Another target of interest is EZH2, a protein involved in controlling which genes are turned on or off in cells. Mutations in the EZH2 gene are found in some follicular lymphomas and contribute to cancer development. Drugs that inhibit EZH2 are being tested in clinical trials, both alone and in combination with other therapies. Early results suggest these drugs can shrink tumors in some patients, with side effects including low blood counts, fatigue, and nausea.^[9]

Immunotherapy drugs beyond monoclonal antibodies are also under investigation. These include drugs that help the immune system recognize and attack cancer cells by blocking proteins that normally prevent immune responses. For example, checkpoint inhibitors target proteins like PD-1 or PD-L1 that cancer cells use to hide from the immune system. When these proteins are blocked, T cells can better identify and destroy lymphoma cells. Clinical trials are testing whether these drugs, used alone or with other treatments, can help patients with relapsed follicular lymphoma. Side effects can include immune-related problems where the activated immune system attacks normal tissues, causing inflammation in organs such as the lungs, liver, intestines, or endocrine glands.^[9]

Bispecific antibodies are engineered molecules that can bind to two different targets simultaneously, such as a protein on cancer cells and another on immune cells, bringing them together so the immune cells can destroy the cancer. Several bispecific antibodies targeting CD20 on lymphoma cells and CD3 on T cells are being studied in clinical trials for relapsed follicular lymphoma. Preliminary results show promising response rates, with tumors shrinking in a significant proportion of patients. Side effects can include cytokine release syndrome, similar to that seen with CAR T-cell therapy, though usually milder.^[9]

Clinical trials for follicular lymphoma are being conducted at major cancer centers in the United States, Europe, and other regions around the world. Eligibility for trials depends on many factors, including the stage and grade of the disease, previous treatments received, how well organs like the heart, liver, and kidneys are functioning, and the patient’s overall health status. Patients interested in participating in a clinical trial should discuss this option with their oncologist, who can help identify suitable trials and explain the potential benefits and risks.^[9]

Most common treatment methods

• Radiation therapy
  • Uses high-energy rays to kill cancer cells in localized areas
  • Often used for early-stage recurrent disease affecting one or a few lymph nodes
  • Can achieve long-term remission in about half of patients with Stage I disease
  • Side effects include fatigue and skin changes in treated areas
• Monoclonal antibody therapy
  • Rituximab is the most commonly used antibody drug, targeting CD20 protein on B cells
  • Helps the immune system recognize and destroy lymphoma cells
  • Can be used alone or combined with chemotherapy
  • Side effects include infusion reactions such as fever, chills, or rash
• Chemotherapy
  • Multiple drug combinations used, including bendamustine with rituximab, R-CHOP, and R-CVP regimens
  • Treatment typically given in cycles over several months
  • Side effects include fatigue, nausea, hair loss, low blood counts, and increased infection risk
  • Most side effects are temporary and resolve after treatment ends
• Stem cell transplantation
  • Involves high-dose chemotherapy followed by infusion of healthy stem cells
  • Can use patient’s own cells (autologous) or donor cells (allogeneic)
  • Reserved for patients with multiple relapses or treatment-resistant disease
  • Significant risks include infection, organ damage, and graft-versus-host disease
• CAR T-cell therapy
  • Patient’s own T cells are genetically modified to attack lymphoma cells
  • Approved for certain patients with relapsed follicular lymphoma
  • Can cause serious side effects including cytokine release syndrome and neurological problems
  • Has shown remarkable results in some patients who did not respond to other treatments
• Targeted therapies (in clinical trials)
  • BCL-2 inhibitors block proteins that help cancer cells survive
  • EZH2 inhibitors target genetic mutations found in some follicular lymphomas
  • Bispecific antibodies bring immune cells and cancer cells together for destruction
  • Checkpoint inhibitors help the immune system recognize and attack cancer cells