What is the Difference Between CLL and Multiple Myeloma

The key difference between CLL and multiple myeloma is that CLL (Chronic lymphocytic leukemia) is a blood cancer that develops in a specific type of lymphocyte called B cells in the bone marrow, while multiple myeloma is a blood cancer that develops in plasma cells, which are white blood cells that originate from B cells in response to an infection.

Most blood cancers are hematologic cancers that start in the bone marrow. Bone marrow is the place where blood cells originate. Blood cancers are due to abnormally growing blood cells that interrupt the function of normal blood cells, fight off infections and produce new blood cells. The main types of blood cancers are leukemia (CLL), Non-Hodgkin lymphoma, Hodgkin lymphoma, and multiple myeloma.

CONTENTS

1. Overview and Key Difference
2. What is CLL  
3. What is Multiple Myeloma
4. Similarities – CLL and Multiple Myeloma
5. CLL vs Multiple Myeloma in Tabular Form
6. Summary – CLL vs Multiple Myeloma

What is CLL (Chronic Lymphocytic Leukemia)?

Chronic lymphocytic leukemia (CLL) is a blood cancer that develops in B cells found in the bone marrow. It is the most common type of leukemia in western countries. The American Cancer Society (ACS) has estimated that there were approximately 21250 cases of CLL in 2021. CLL tends to develop slowly. Normally, lymphocytic leukemias are leukemias that develop in a type of white blood cell called lymphocytes. CLL develops in a specific type of lymphocyte in the bone marrow called B cells. Healthy B cells help the body fight infections, while leukemic B cells can’t fight infections in the same manner.

The exact cause of CLL is not known. But risk factors include family history, age (average age of CLL is 70), sex assigned at birth (men develop more CLL), ethnicity (common in people living in North America, Europe and less common in people living in Asia), Agent Orange exposure (Agent Orange is a chemical used in Vietnam war that linked with higher cases of CLL), and monoclonal B cell lymphocytosis (monoclonal B cell lymphocytosis elevates the level of lymphocytes that can turn into CLL).

The symptoms of CLL include getting infections often, anemia, bleeding, bruising more easily, high temperature, night sweats, swollen glands in the neck, armpit, or groin, swelling and discomfort in the tummy, and unintentional weight loss. This condition can be diagnosed through family history, physical examination to check swollen glands, blood tests, bone marrow biopsy, lymph node biopsy, imaging testing (X-ray, ultrasound, CT scan), and genetic testing. Furthermore, treatment options for CLL include chemotherapy medicines (fludarabine, cyclophosphamide, retuximab), radiotherapy, antibiotics, antifungals, blood transfusion, immunoglobulin replacement therapy, injecting granulocyte colony-stimulating factor (G-CSF), and stem cell or bone marrow transplant.

What is Multiple Myeloma?

Multiple myeloma is a blood cancer that develops in plasma cells, which are white blood cells that originate from B cells in response to infection. Plasma cells play an important role in the immune system due to their ability to produce antibodies. In people who suffer from multiple myeloma, the abnormal plasma cells replicate and abnormally crowd out the healthy blood cells. The actual cause is unknown. The risk factors include age (develop people under 45 years age), sex assigned at birth (men have a more likely hood to develop this condition), race and ethnicity (black people suffer more), radiation (exposure to X-ray), weight (overweight people have higher risk), and family history.

The symptoms of this condition may include bone pain, nausea, constipation, loss of appetite, mental fogginess, fatigue, frequent infections, weight loss, weakness or numbness in the legs, and excessive thirst. Moreover, multiple myeloma can be diagnosed through blood tests, urine tests, examination of the bone marrow, imaging testing (X-ray, MRI, CT scan, or PET scan), and genetic testing. Furthermore, the treatment options may include targeted therapy, immunotherapy, chemotherapy drugs (cyclophosphamide, etoposide, doxorubicin, liposomal doxorubicin, melphalan, bendamustine), corticosteroids, bone marrow transplant, and radiation therapy (high power beams such as X-ray or protons).

What are the Similarities Between CLL and Multiple Myeloma?

• CLL and multiple myeloma are two main types of blood cancers.
• In both cancers, the conditions are likely to run in families, and men are more likely to contract them than women.
• Both cancers are most common in older adults.
• They may show similar symptoms such as fever, fatigue, frequent infection, unexplained weight loss, loss of appetite, bone loss, swollen lymph nodes, and unusual bruising or bleeding.
• They can be treated through chemotherapy, radiation therapy, and stem cell transplant.

What is the Difference Between CLL and Multiple Myeloma?

CLL is a blood cancer that develops in a specific type of lymphocyte called B cells in the bone marrow, while multiple myeloma is a blood cancer that develops in plasma cells, which are white blood cells that originate from B cells in response to infection. Thus, this is the key difference between CLL and multiple myeloma. Furthermore, the risk of developing CLL is 6 times higher if the patient has a parent with CLL. On the other hand, the risk of developing multiple myeloma is 2 times higher if the patient has a parent with multiple myeloma.

The below infographic presents the differences between CLL and multiple myeloma in tabular form for side by side comparison.

Summary – CLL vs Multiple Myeloma

CLL and multiple myeloma are two main types of blood cancers. CLL develops in a specific type of lymphocyte called B cells in the bone marrow, while multiple myeloma develops in plasma cells which are white blood cells that originate from B cells in response to infection. So, this is the key difference between CLL and multiple myeloma.

Reference:

1. “Chronic Lymphocytic Leukemia Treatment (PDQ®)–Patient Version.” National Cancer Institute.
2. “Multiple Myeloma: Symptoms, Causes, Diagnosis and Treatment.” WebMD.

Image Courtesy:

1. “Chronic Lymphocytic Leukemia” By Ed Uthman – originally posted to Flickr as Chronic Lymphocytic Leukemia, (CC BY-SA 2.0) via Commons Wikimedia
2. “Multiple Myeloma” By Scientific Animations (CC BY-SA 4.0) via Commons Wikimedia