Splenic Marginal Zone Lymphoma - Symptoms, Diagnosis, and Treatment

What Is Splenic Marginal Zone Lymphoma (SMZL)?

Splenic marginal zone lymphoma is a group of slow-growing (indolent), B-cell non-hodgkin’s lymphoma. It is a rare lymphoma. Lymphomas are cancers that develop from the white blood cells called lymphocytes, which help the body fight infections. Splenic marginal zone lymphoma affects the lymphocytes called B cells. SMZL develops when these B cells become abnormal cancerous cells. It affects the spleen, blood, and bone marrow.

What Are the Types of Marginal Zone Lymphomas?

Marginal zone lymphomas are of three types.

They are

1. Splenic Marginal Zone Lymphoma - This is the rarest form. It is linked with hepatitis C and Kaposi sarcoma virus.

2. Nodal Marginal Zone B Lymphoma - This lymphoma begins in the lymph nodes.

3. Mucosa-associated lymphoid tissue lymphoma (extranodal marginal zone lymphoma) is the most common form of marginal zone lymphoma. It can affect different body parts like the lungs, digestive system, skin, eyes, etc.

What Are the Symptoms Associated With Splenic Marginal Zone Lymphoma?

Symptoms may not be present in all cases. About 1 in 4 patients do not have any symptoms in the earlier stages.

Common symptoms of SMZL include

• Splenomegaly (enlarged spleen) - The spleen enlarges due to the accumulation of abnormal lymphoma cells. Splenomegaly causes

  • Discomfort or pain in the upper part of the abdomen.

  • Feeling full after eating a little food.

  • Pain in the left shoulder.

• Cytopenia - Low blood cell count can make the patient more susceptible to infections.

• Anemia - Low levels of red blood cells can cause tiredness and breathlessness.

• Thrombocytopenia - Low levels of platelets, which can lead to bleeding and bruising problems.

• Fever without an infection.

• Sometimes, the lymphoma cells produce an abnormal protein called globulin, making the blood thicker. This can lead to nosebleeds, headaches, confusion, and blurred vision.

• In some cases, SMZL causes symptoms, which include

  • Unexplained weight loss.

  • Fever.

  • Night sweats.

• In some cases, autoimmune disorders like rheumatoid arthritis, primary biliary cirrhosis, etc., may develop.

What Are the Causes of Splenic Marginal Zone Lymphoma?

• There are no known causes for SMZL.

• It is more common in older people ( above 65 years old).

• People with hepatitis C infection are more likely to get SMZL.

How Is Splenic Marginal Zone Lymphoma Diagnosed?

Doctors use blood tests, bone marrow tests, scans, and other lab tests to diagnose splenic marginal zone lymphoma.

• Blood Tests - A complete blood count is done in all cases to help diagnose SMZL. Blood levels of certain molecules present in cancer are also checked.

• Bone Marrow Tests - check whether cancer has spread to bone marrow.

• Laboratory Tests - Spleen and bone marrow samples are sent to a lab to study the abnormal cells further. Histology is done to study and identify the type of lymphoma.

• Surgery - Sometimes, splenectomy is done even before the cancer is diagnosed. A part of the removed spleen is then used to study the case further.

• Other tests may be done to discover other related health conditions.

  • Testing for hepatitis C viral infection.

  • Tests to check for autoimmune disorders.

  • Tests to look for abnormal antibodies produced by cancer cells.

• Imaging Tests - X-rays, ultrasounds, CT scans, and MRIs may also be done for better diagnosis.

What Are the Stages of Splenic Marginal Zone Lymphoma?

• After the diagnostic tests, the doctor can assess how far the cancer has spread and what areas it has affected. Based on this, the lymphoma is staged through a process called staging.

• Lymphomas may be grouped into low-grade (slow-spreading) and high-grade ( faster spreading). Splenic marginal zone lymphomas are usually low-grade lymphomas. However, in some rare cases, it may turn into high-grade lymphomas.

How Is Splenic Marginal Zone Lymphoma Treated?

SMZL is a rare, slow-growing lymphoma, so no standard treatment exists. The treatment plan considers the symptoms and the patient's overall health. Some of the treatment options for SMZL include

Watch and Wait

SMZL is slowly growing, and often, the symptoms do not appear for a long time. If there are no symptoms, treatment can be delayed. The patient is regularly watched for any cancer progress during the waiting period. Delaying the treatment can also protect the patient from unpleasant side effects.

Chemotherapy

Various treatment options aim to control the lymphoma for as long as possible (remission). Chemotherapy is used alone or in combination with immunotherapy to control growth. Some of the combinations used in chemotherapy are

• CHOP - Cyclophosphamide, Adriamycin, Vincristine, and Prednisone

• CVP - Cytoxan, Oncovin, and Prednisone.

• FND - Fludarabine, Mitoxantrone, and Dexamethasone .

Targeted Therapy

Rituximab is a drug often used to treat splenic marginal zone lymphoma. Rituximab controls lymphoma by targeting certain molecules on the surface of cancer cells. Targeting these cancer cells limits the harm done to normal cells. It is used alone or in combination with chemotherapy. R-CVP and R-CHOP are the most commonly used combinations

Surgery

Splenectomy is the surgery done to remove the spleen. In some cases, a splenectomy is done. Many symptoms of SMZL are controlled after splenectomy. Since medications have become more effective in treating SMZL, splenectomy is done only in rare cases.

Radiation Therapy

External beam radiation to the spleen is done to control cancer. Radiation can occur when the patient is symptomatic but not healthy enough to undergo surgery or chemotherapy.

Steroids

Steroids are used along with chemotherapy to increase its effectiveness.

Antiviral Drugs

First-line antiviral drugs are given to SMZL patients with hepatitis C infection.

What Is the Outlook for Splenic Marginal Zone Lymphoma?

SMZL usually has a good prognosis in the majority of cases. People live for an average of ten years after diagnosis. However, in some cases, they are more aggressive and have a poor outlook.

Some factors that affect the outlook of remission and long-term survival include

• Age of the patient.

• Stage in which the lymphoma is diagnosed.

• Poor overall health.

• Gene mutations within the cancer cells.

• Cancer cells outside the spleen and bone marrow.

• Enlarged lymph nodes.

• Low red blood cells and platelets.

Conclusion

Splenic marginal zone lymphoma is characterized by the abnormal growth of B-cells in the spleen's marginal zone. It may initially present with vague symptoms or incidental findings. Splenic marginal zone lymphoma is a slow-growing lymphoma; early diagnosis can greatly impact the patient's long-term survival. In addition, making small lifestyle changes, like eating healthy and being active, helps with a better outlook. Even though it is slow-growing, SMZL can still affect patients' health and quality of life. This shows how important it is to keep getting medical check-ups and make healthy lifestyle changes to improve outcomes and well-being.