The term “marginal zone lymphoma” describes a group of indolent—or slow-growing, non-aggressive—non-Hodgkin B-cell lymphomas. This means it refers to cancer of the lymphatic system that results from the body making abnormal B lymphocytes, which are white blood cells that, when healthy, help the immune system fight off infections. B cells are produced in the bone marrow. Once they mature, they circulate through the lymphatic system, a network of nodes and vessels that transport lymph fluid to all bodily tissues.

Marginal zone B-cell lymphoma as a whole is considered rare, with an estimated 1,000 to 2,300 new cases per year, according to the Leukemia & Lymphoma Society. The World Health Organization recognizes three subtypes of marginal zone lymphoma:

Mucosa-associated lymphoid tissue (MALT) lymphoma, a malignancy that develops outside of the lymph nodes in places like the stomach, thyroid, eyes and lungs and accounts for 70% of all marginal zone lymphoma cases
Nodal, which affects the lymph nodes and represents 20% of cases
Splenic, which affects the spleen, blood and bone marrow and makes up about 10% of cases

Causes and risk factors of marginal zone lymphoma

Researchers in the general medical community are still working to pinpoint the root cause of lymphoma. As with other forms of cancer, lymphoma occurs when DNA changes lead to cell mutations that cause abnormal cell development and reproduction. When abnormal lymphocytes multiply uncontrollably, they can crowd out healthy cells and undermine the body’s defenses against infection and parasites.

Why these DNA changes occur isn’t yet fully understood, but scientific research has identified some risk factors for marginal zone lymphoma and its specific subtypes. In general, people diagnosed with marginal zone lymphoma usually are adults age 50 or older with a family history of lymphoma, autoimmune diseases or susceptibility to certain types of infection.

Specific risk factors have also been identified for each of the marginal zone lymphoma subtypes. For example, MALT lymphoma has been linked to inflammation caused by H. pylori bacterial infections and autoimmune diseases such as Hashimoto’s disease and Sjögren’s syndrome. Both nodal and splenic marginal zone lymphoma have been linked to hepatitis C infections.

It’s important to note that risk factors indicate a potentially higher possibility of developing a specific condition. There are many people who have these risk factors who will never develop marginal zone lymphoma, as well as people with no known risk factors who will.

Signs and symptoms of marginal zone lymphoma

As with risk factors, the typical symptoms of marginal zone lymphoma can vary according to the subtype. However, the following symptoms are associated with all forms of the disease:

Unexplained weight loss
Chest or belly pain
Fever without having an infection
Night sweats
Skin rash
Fatigue

Additional symptoms associated with MALT lymphoma include indigestion, nausea and vomiting. People with nodal marginal zone lymphoma may discover a painless lump in their armpit, neck or groin area. And due to an enlarged spleen that presses on the stomach, those who have splenic marginal zone lymphoma may feel full or uncomfortable after eating only small amounts of food.

Diagnosing marginal zone lymphoma

When a patient has suspicious symptoms and a family or medical history associated with marginal zone lymphoma, the consulting physician will likely conduct a physical exam that includes checking the lymph nodes and other areas for signs of swelling. If lymphoma is suspected, the patient may undergo testing that can include:

Blood tests to check for viral and bacterial infections
A complete blood count (CBC) analysis that measures white blood cells, red blood cells and platelets in the blood
Bone marrow aspiration, which involves removing and analyzing a marrow sample from inside a bone to check for the presence of abnormal lymphocytes
Imaging tests, such as computed tomography (CT) scans

In most cases, a diagnosis of the marginal zone lymphoma subtype is confirmed through a biopsy. This may involve removing the spleen, a lymph node or a portion of a lymph node and sending the tissue sample to a laboratory for analysis by a trained pathologist. If the sample contains cancerous cells, the pathologist will perform additional testing to determine which type of marginal zone lymphoma is present. It’s vital to diagnose the specific subtype so that oncologists can select the most effective treatment options.

Marginal zone lymphoma treatment

The best treatment plan for marginal zone lymphoma depends on the subtype, location and stage of the malignancy, the patient’s age and overall health condition and other factors. If a patient has MALT lymphoma of the stomach, for example, treatment is likely to start with antibiotic and antacid medications because this type of lymphoma often results from an H. pylori bacterial infection. In some cases, after several months of taking these medications, the lymphoma may go away and the treatment may switch to monitoring the condition for signs of a relapse.

Generally, marginal zone lymphoma is slow to metastasize (spread), so cancer specialists often take a “watchful waiting” approach to treatment. This involves monitoring the patient’s condition through regular checkups that may include lab and imaging tests. Some additional treatments for marginal zone lymphoma are:

Chemotherapy
Immunotherapy
Radiation therapy
Stem cell transplantation
Targeted therapies, i.e., rituximab
Surgery (removal of the spleen)

Moffitt Cancer Center’s approach to marginal zone lymphoma

As the only cancer hospital based in Florida to be designated a Comprehensive Cancer Center by the National Cancer Institute, Moffitt is a recognized leader in cancer diagnosis and treatment, including for all types of lymphoma. Our widely respected Malignant Hematology Program includes a highly skilled team of lymphoma specialists who have the services of an on-site pathology lab at their fingertips to help them efficiently diagnose and treat marginal zone lymphoma and other rare types of cancer. And our patients benefit from our individualized approach to cancer treatment, which means every Moffitt patient receives a tailored treatment plan based on their cancer diagnosis and the many factors that are unique to them.

New patients are welcome at Moffitt, whether they’re seeking an initial diagnosis, a second opinion or treatment for a diagnosed cancer condition. No referral is required. Connect with us by calling 1-888-663-3488 or fill out our onlinenew patient registration form. As Florida’s top cancer hospital, we’re changing the traditional patient care model so that every new patient is connected with a cancer expert within a day of their reaching out.