Difference Between Leukemia and Multiple Myeloma

The key difference between Leukemia and Multiple Myeloma is that Leukemia is a blood born cancer in which the bone marrow and other blood-forming organs such as spleen and lymph nodes produce increased numbers of immature or abnormal leukocytes (white blood cells) while Multiple myeloma is a special type of blood born cancer where abnormal plasma cells proliferate and infiltrate blood-forming organs such as bone marrow, spleen and lymph nodes. However, in multiple myeloma, abnormal plasma cells can sometimes spill into blood, causing plasma cell leukemia.

What is Leukemia?

Leukemia or abnormal proliferation of white blood cells can originate from any type of white blood cells.

  • Lymphocytes – Lymphocytic leukemia
  • Myelocytes – Myelocytic leukemia
  • Eosinophils – Eosinophilic leukemia

These cancers can be acute or chronic as well as can represent any stage of white blood cell maturation (e.g. blasts – acute lymphoblastic leukemia). Acute lymphoblastic leukemia is usually seen among children while chronic myeloid leukemia is usually seen among adults. The rate of progression can vary among these malignancies. Leukemias originate from genetic mutations which can occur spontaneously or with exogenous stimuli such as radiation and toxic chemicals. Presentation of leukemia is usually nonspecific. Due to the fast proliferation of abnormal blood cells, normal cell lines of the bone marrow get suppressed, causing a reduction of those cells (reduced red blood cell line causing anemia, reduced platelets). Abnormal cells can infiltrate other blood-forming organs such as spleen, liver, and lymph nodes. When the disease is severe, it can affect other non-blood forming organs such as the brain, lungs, and testis. As the presentation is non-specific, multiple myeloma is usually diagnosed late.

Simple blood smear under the microscope can show abnormal cells and will give the diagnosis. More detailed diagnosis can be made using advanced techniques such as flow cytometry and immune histochemistry.  All patients need careful assessment of the extent of the disease. Treatment includes a combination of chemotherapy, radiation therapy, targeted therapy, and bone marrow transplant, in addition to supportive care and palliative care as needed. Prognosis depends on the underlying genetic mutation and the type of cancer.

What is Multiple Myeloma?

Multiple myeloma or the abnormal proliferation of plasma cells is associated with a spectrum of abnormalities which includes an increase in serum calcium levels and an increase in the thickness of blood due to para-proteins secreted by abnormal plasma cells. Also, these patients get bone marrow suppression when the plasma cells infiltrate the bone marrow. Ultimately they can get renal failure due to multiple reasons.

Diagnosis of multiple myeloma is done with blood tests (serum protein electrophoresis, serum free kappa/lambda light chain assay), urine protein electrophoresis, bone marrow examination, and X-rays of bones. Multiple myeloma is incurable, but it is treatable. Remissions may be induced with steroids, chemotherapy, immunomodulatory drugs such as thalidomide or lenalidomide, and stem cell transplants. Radiation therapy is sometimes used to reduce pain from bone deposits.

What is the difference between Leukemia and Multiple Myeloma?

Definition of Leukemia and Multiple Myeloma   

Leukemia: Leukemia is a blood born cancer in which the bone marrow and other blood-forming organs produce increased numbers of immature or abnormal leukocytes.

Multiple myeloma: Multiple myeloma is a special type of blood born cancer where abnormal plasma cells proliferate and infiltrate blood-forming organs such as bone marrow, spleen and lymph nodes.

Characteristics of Leukemia and Multiple Myeloma   

Pathophysiological Basis

Leukemia: Leukemia is referred to the as malignant proliferation of white blood cells such as lymphocytes and Myelocytes.

Multiple myeloma: Myeloma is referred to as the malignant proliferation of plasma cells.

Age Distribution

Leukemia: Leukemia can occur in any age group.

Multiple myeloma: Myeloma occurs in the elderly population.

Complications

Leukemia: Leukemia usually does not cause renal failure, hyperkalemia, and paraproteinemia.

Multiple myeloma: Myeloma causes renal failure, hyperkalemia, and paraproteinemia.

Diagnosis

Leukemia: Leukemia is diagnosed by blood pictures, flow cytometry, and immune histochemistry.

Multiple myeloma: Myeloma is diagnosed with serum protein electrophoresis, serum free kappa/lambda light chain assay), bone marrow examination, urine protein electrophoresis, and X-rays of bones.

Treatment

Leukemia: Leukemia is treated with chemoradiation.

Multiple myeloma: Myeloma is treated with steroids and immunomodulatory agents such as thalidomide or lenalidomide.

Prognosis

Leukemia: Leukemia has a variable prognosis. Some types of leukemias can be cured.

Multiple myeloma: Myeloma  generally has a poor prognosis and thought to be incurable.

 

Image Courtesy:

“Symptoms of leukemia” by Mikael Häggström – All used images are in public domain.(Public Domain) via Commons

“Blausen 0656 MultipleMyeloma” by Blausen Medical Communications, Inc. – Donated via OTRS, see ticket for details.(CC BY 3.0) via Commons