What Is Follicular Lymphoma?

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Follicular lymphoma is a slow-growing form of non-Hodgkin's lymphoma (NHL). Lymphomas are grouped into two categories—Hodgkin's and non-Hodgkin's. Non-Hodgkin's lymphoma starts in lymphocytes, a type of white blood cell. Follicular lymphoma accounts for 20%–30% of all NHL cases.  

Follicular lymphoma is a chronic condition that is not usually curable. This can be scary to hear. However, people can live many years with follicular lymphoma.

This article will discuss symptoms, diagnosis, and prognosis for follicular lymphoma. It will also go into the types of treatments you may need, and provide insight into coping with this condition.  

Woman feels swollen neck lymph nodes, a symptom of follicular lymphoma

Moyo Studio / Getty Images

What Is Follicular Lymphoma?

Follicular lymphoma is an indolent (slow-growing, or low-grade) cancer that starts in the lymph nodes. Lymph nodes are part of the lymphatic system, which is part of the immune system.

Lymph nodes are located in many areas of the body, including:

  • Armpits
  • Neck
  • Chest
  • Stomach
  • Groin

Like most types of non-Hodgkin’s lymphoma, follicular lymphoma originates in white blood cells called B lymphocytes (B cells). B cells are necessary for producing antibodies that fight infection. Follicular lymphoma occurs when the healthy B cells in lymph nodes become cancerous, proliferating and growing uncontrollably.

When viewed under a microscope, follicular lymphoma cells appear clumped together in clusters or follicles. Over 90% of people with follicular lymphoma have a specific type of protein called CD20 on the surface of the cancerous follicular cells. This protein is often targeted during treatment.

Symptoms of Follicular Lymphoma

Because it’s slow-growing, you may have follicular lymphoma for several years without experiencing any symptoms.

The most common symptom of this condition is painless swelling in lymph nodes. The lymph nodes most commonly affected are located in the armpits, neck, and groin.

In addition to swollen lymph nodes, symptoms of follicular lymphoma include:

  • Drenching night sweats
  • Chronic fever
  • Extreme weight loss
  • Fatigue
  • Shortness of breath

Causes of Follicular Lymphoma

As with so many types of cancer, the exact cause of follicular lymphoma is unknown. Genetic, environmental, and immunological factors may all play a role.

Approximately 85% of people with follicular lymphoma have a genetic abnormality called a translocation. Translocations are genetic changes that occur within chromosomes. Chromosomes are found in the nucleus of cells. The translocations that cause follicular lymphoma happen within the cells that become cancerous.

Translocations occur when a piece of one chromosome breaks off and attaches itself to a different chromosome. Pieces of chromosomes may also break off and trade places with each other.

In people with follicular lymphoma, a piece of chromosome 14 trades places with a piece of chromosome 18. This causes a mutation to occur in the BCL-2 gene.

The mutated gene inhibits a natural process that regulates cell death, called apoptosis. Since the affected cells don’t die off when they’re supposed to, they continue to grow uncontrollably and become cancerous.

This genetic abnormality is not inherited and has not been shown to run in families. It also does not always cause cancer to occur. Your cells can have this translocation and not become cancerous.

Exposure to environmental toxins may also have an impact. Toxins that may be at fault include:

  • Benzene (industrial chemical derived from coal and petroleum and found in gasoline and manufactured products)
  • Pesticides (chemicals that kill, repel, or control plants and insects)
  • Tobacco smoke

Getting a Diagnosis

Follicular lymphoma usually occurs in people aged 50 and over. The average age at diagnosis is 60 years old. Since follicular lymphoma is slow-growing, you may have it and not know it for a long time.

This condition is often discovered through imaging tests for other complaints. Swollen masses may also be felt by you or by your healthcare provider during a checkup. In around 80%–85% of cases, symptoms aren't discovered until the cancer has progressed to stage 3 or 4.

If you have a swollen mass in a lymph node, a biopsy will be done. In a biopsy, an entire lymph node or a small piece of it will be removed and checked for cancer cells in a laboratory.

If a diagnosis of follicular lymphoma is confirmed by the biopsy, additional testing will be done to determine what stage the cancer is in. Staging describes how the cancer has spread. This helps your oncologist (doctor specializing in diagnosing and treating cancer) determine the best type of treatment for you.

Additional tests may include blood tests to measure blood cell counts, imaging tests to view your internal organs and lymph nodes, and a bone scan to check for spread. Tests to expect include:

Treatment for Follicular Lymphoma

Follicular lymphoma is difficult to cure. Many treatments are designed to arrest spread and reduce symptoms. Follicular lymphoma is typically treated as a chronic condition you live with for many years. However, everyone is different. Your treatment will be tailored specifically to address your condition and needs.  

If you are asymptomatic (have no symptoms), you may not receive any form of treatment. Instead, your doctor may suggest active surveillance, also called watchful waiting. This usually requires regular testing at three-month intervals to keep an eye on changes in symptoms and disease progression.

In some instances, a monoclonal antibody treatment called Rituxan (rituximab) may be prescribed, even if you are asymptomatic. Rituxan targets the CD20 protein found on the surface of cancer cells.

Rituxan is also used as a first-line treatment for symptomatic disease alone or with chemotherapy. This treatment is referred to as immunochemotherapy.

If you're experiencing symptoms or have pain or discomfort associated with the disease, radiation or chemotherapy may be recommended. Chemotherapy for follicular lymphoma may be administered intravenously or orally.

Targeted therapy drugs such as Revlimid (lenalidomide) may be used along with Rituxan for symptomatic follicular lymphoma.

Treatment for Relapsed / Refractory Follicular Lymphoma

Many people with follicular lymphoma go into long remission periods of many years after having treatment. However, this disease can return.

If you are diagnosed with relapsed follicular lymphoma, your disease has come back after a period of remission. In some instances, you may not respond well to treatment or you may have a short, symptom-free period. If you are diagnosed with refractory follicular lymphoma, your disease has not responded well to prior treatments.

The treatments recommended for relapsed or refractory follicular lymphoma will be based on your age, health, and response to initial treatment. Second-line therapies may include some of the same treatments provided earlier, as well as newer forms of treatment, such as:

What Is Transformation?

Follicular lymphoma occasionally transforms (changes) into an aggressive, fast-growing form of lymphoma called diffuse large B-cell lymphoma (DLBCL). Transformation occurs in two or three out of every 100 people with follicular lymphoma.

Your doctor will monitor you for symptoms of transformation, which include:

  • Night sweats
  • Rapidly enlarging lymph nodes
  • Weight loss
  • Persistent fever
  • Back pain

DLBCL may be more challenging to treat than follicular lymphoma. Treatments may include strong chemotherapy, stem cell transplant, or chemoimmunotherapy. Your doctor may also recommend you do a clinical trial.

Prognosis

Follicular lymphoma is a chronic, lifelong disease. You can live for many years or even decades with this condition, both before and after treatment.

Your prognosis may be estimated with a tool called the Follicular Lymphoma International Prognosis Index (FLIPI). FLIPI adds up your risk factors to estimate a prognosis. The more risk factors you have, the less optimistic your estimated prognosis may be. They include:

  • You're over 60 years old.
  • You're in stage 3 or stage 4.
  • Your hemoglobin level is under 12.0 grams per deciliter (this is the protein that transports oxygen in red blood cells).
  • You have more than four affected lymph node areas.
  • You have a higher than normal serum lactate dehydrogenase (LDH) level (this is an indicator of tissue damage).

Your estimated prognosis may also be determined with data accrued through the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database. SEER tracks five-year relative survival rates based on the amount of cancer spread.

The five-year relative survival rate for this condition is an estimate of the experiences of people who were diagnosed with follicular lymphoma at least five years ago. Treatment for follicular lymphoma has continued to improve since that time. These figures are estimates only and not necessarily predictive of what will happen in your case:

  • Localized (cancer is limited to one lymph node area or lymph node organ, or one organ not in the lymph system): 97%
  • Regional (cancer has spread into a nearby organ or is in two or more lymph node areas on the same side of the diaphragm): 91%
  • Distant (cancer has spread to distant areas of the body): 86%

Coping With Follicular Lymphoma

Since it is a slow-growing cancer, follicular lymphoma often comes with excellent outcomes and long survival times. Even so, it can be challenging and stressful to live with a condition that is considered incurable. This may be true during asymptomatic as well as symptomatic periods.

Coping may be easier if you connect with others who have this condition. Consider joining the Living with Follicular Lymphoma global community online group if you're on Facebook. Here you can connect with others, ask questions, and find support.

Living a healthy lifestyle is also a viable strategy that may help you deal with the side effects of treatment, plus provide you with physical and emotional strength. Eating healthy food, not smoking, and exercising are all beneficial. So is overcoming stress through yoga, meditation, and spending time in natural surroundings.

Summary

Follicular lymphoma is a slow-growing type of non-Hodgkin's lymphoma, a cancer of a type of white blood cells. As these cells form clusters in the lymph nodes, the nodes may be enlarged, but often there are few symptoms.

Diagnostic testing includes a lymph node biopsy, blood tests, and imaging. Treatment may be with watchful waiting, Rituxan, and chemotherapy. The prognosis is usually good, although the condition is chronic and has the possibility of transforming into a more aggressive type of lymphoma.

A Word From Verywell

Finding out you have follicular lymphoma can come as an unwelcome shock. You may be worried about the treatments you’ll need, or your prognosis. Treatments for follicular lymphoma have improved significantly over the years.

Clinical trials are also ongoing and may yield exciting new strategies that prolong life and reduce symptoms. There is lots of room for optimism and hope.

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10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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