Marginal Zone Lymphoma (MZL)

Marginal zone lymphoma (MZL) refers to a group of rare, slow-growing non-Hodgkin lymphomas. They typically develop in lymphoid tissue, like lymph nodes, spleen or bone marrow. But they can also develop outside of your lymph nodes (“extranodal”). Lymphoid tissue contains B cells, a type of white blood cell that’s in parts of your immune system like your lymph nodes and spleen.

MZL is an “indolent” lymphoma. This means it typically progresses very slowly. You can have it for a long time without having any issues. Many people with this diagnosis go for years without needing treatment.

Still, everyone’s experience is different. For instance, although it’s uncommon, MZL can transform into an aggressive cancer called diffuse large B-cell lymphoma.

Your situation depends on things like the type of MZL, whether you have symptoms and how effective treatment is.

Types

There are three types of marginal zone lymphoma (MZL):

• MALT lymphoma: This is the most common type. MALT stands for “mucosa-associated lymphoid tissue.” Most often, MALT lymphoma develops in the lining of your stomach (gastric MALT). But it can also start in your lungs, skin, thyroid gland, salivary gland, bowels or near your eye (non-gastric MALT).
• Nodal marginal zone lymphoma: This type affects your lymph nodes. It may cause them to enlarge.
• Splenic marginal zone lymphoma: This kind affects your spleen, blood and bone marrow. It may cause your spleen to enlarge.

Symptoms of marginal zone lymphoma

This condition often grows very slowly. If you develop symptoms, they may vary depending on where the lymphoma is in your body. In general, symptoms include:

• Belly (abdomen) pain or discomfort
• Fatigue
• Feeling full when you haven’t eaten much
• Nausea (the sensation of needing to vomit)
• Vomiting

MZL can sometimes cause symptoms that tend to occur in more advanced lymphomas (B-symptoms). B-symptoms can be a sign that MZL has transformed into an aggressive lymphoma. They are:

• Drenching night sweats
• Fever
• Unexplained weight loss

Marginal zone lymphoma causes

Marginal zone lymphoma happens when B cells in what experts call the “marginal zone” in lymph tissue mutate (change). They become abnormal cells that multiply out of control.

People with MZL often have infections or autoimmune diseases that cause long-term inflammation. Having a family history of lymphoma may increase your risk of MZL. Causes can vary by subtype:

• MALT lymphoma happens more commonly in people with chronic stomach inflammation from an H. pylori infection. The condition is also linked to other bacterial infections and autoimmune diseases, like Hashimoto’s disease and Sjӧgren’s syndrome.
• Splenic and nodal marginal zone lymphomas are linked to hepatitis C infections. There’s also an association with autoimmune disorders.

Risk factors

These lymphomas usually affect people age 60 and older. The most common type, gastric MALT lymphoma, is more common in males.

Complications of this condition

In some people, marginal zone lymphoma transforms into large B-cell lymphoma. Unlike MZL, this cancer is aggressive.

Recent research that studied the health of people with MZL found that 5 out of 100 had MZL transform into a B-Cell lymphoma within 5 years. That number increased to 8 out of 100 in 10 years. 

How doctors diagnose this condition

Often, healthcare providers diagnose the condition in people who don’t have symptoms. Signs of MZL may show up on testing done for other reasons.

Once your provider suspects an issue, they’ll ask if you have any symptoms. They’ll review your medical history and your family’s medical history. You’ll need tests that may include:

• Blood tests: You may need blood work to check for abnormal blood counts or infections. Tests can check the health of your organs and detect signs of cancer in your blood.
• Imaging tests: Imaging that shows signs of cancer includes PET scans and CT scans.
• Biopsy: Your provider may remove a sample of tissue or fluid to test for cancer cells.

MZL stages

Healthcare providers use cancer staging systems to plan treatment and predict your outlook (prognosis). MZL stages are:

• Stage I: Cancer in one lymphatic area
• Stage II: Cancer in two or more lymphatic areas on the same side of your diaphragm
• Stage III: Cancer in several lymphatic areas on both sides of your diaphragm
• Stage IV: Cancer that’s spread beyond lymphatic tissue

How is marginal zone lymphoma treated?

You may not need treatment right away if you don’t have symptoms. Instead, your healthcare provider may monitor your health. They’ll provide treatment only when it’s necessary. For instance, you may start treatment if your blood test results show the MZL is progressing. You might need treatment to help improve your quality of life. This is “watchful waiting,” or active surveillance.

Treatments include:

• Medicine for infections: Antibiotics to treat H. pylori infections often cure early-stage gastric MALT. You may need antivirals for hepatitis C infection if it’s related to MZL.
• Radiation therapy: This treatment sometimes cures early-stage MZL.
• Immunotherapy: Rituximab is a common immunotherapy treatment for MZL. It helps your immune system fight cancer. You may get it alone or with chemotherapy.
• Splenectomy: Spleen removal surgery may help if an enlarged spleen is causing symptoms.
• Targeted therapy: You may access new therapies through a clinical trial. New treatments being studied for effectiveness in MZL include lenalidomide, BTK inhibitors and CAR-T cell therapy. This may be the best option if your condition is hard to treat.

When should I see my healthcare provider?

Contact your provider if you have new or worsening symptoms. If you’re getting treatment, let them know if you have unexpected side effects.

Is marginal zone lymphoma curable?

That depends on the type and stage. For example, antibiotics that get rid of H. pylori may cure MALT lymphoma. Radiation therapy may cure MZL that’s only in one place, like a lymph node. There’s a much greater chance of a cure if the disease is stage I or stage II.

Other treatments put the condition into remission. Remission happens when cancer treatment eliminates symptoms and tests show no signs of disease. MZL treatments, like rituximab, have helped people with MZL stay in remission for longer. Remission can last for months or even several years. But marginal zone lymphoma often comes back at some point.

What is the survival rate for marginal zone lymphoma?

Survival rates vary based on the type. One study suggests the following:

• An estimated 88 out of 100 of people with extranodal marginal zone lymphoma were alive five years after diagnosis.
• An estimated 79 out of 100 people with splenic marginal zone lymphoma were alive five years after diagnosis.
• An estimated 76.5 out of 100 people with nodal marginal zone lymphoma were alive five years after diagnosis.

More recent research shows that people with MZL are living longer than ever. This is likely because of newer, more effective drug therapies.

It’s important to remember that survival rates are estimates based on other people’s experiences and data collected over time. Your experience may be different.

Marginal zone lymphoma affects people age 60 and older. In many cases, people with this condition ultimately die from causes other than marginal zone lymphoma.

Is there anything I can do to feel better?

Self-care is an important part of living with lymphoma. One of the best things you can do for yourself is to make caring for your needs a part of your routine. This means nourishing your body with the right foods. It also means getting enough physical activity and rest.

Your healthcare provider can work with you to develop habits that put your well-being front and center.