Multiple myeloma is an uncommon cancer affecting plasma cells in the bone marrow. Tumors in the bones and other organs can cause the cells to grow out of control. A complication of this cancer is amyloidosis, and both conditions share some similarities.
The American Cancer Society estimates that approximately
Amyloidosis is a condition associated with multiple myeloma. In amyloidosis, the abnormal plasma cells create many light-chain proteins that can form amyloid deposits. These deposits can cause organ damage. Doctors regard this form of amyloidosis as a complication of multiple myeloma.
Keep reading to learn more about the link between multiple myeloma and amyloidosis, including how doctors might diagnose and treat these conditions.
The plasma cells of the bone marrow are an important part of the immune system. If they become cancerous and grow out of control, doctors call this
Amyloidosis is a group of rare and serious conditions that also involve the plasma cells. Primary amyloidosis, or AL (light chain) amyloidosis is the most common type. Other forms of amyloidosis are unrelated.
AL amyloidosis is closely related to multiple myeloma. It involves the build-up of abnormal light-chain proteins that form amyloid deposits. These deposits can damage organs and tissues throughout the body and make it difficult for them to function properly. Without treatment, amyloidosis can lead to organ failure.
Multiple myeloma and amyloidosis share a common cause: the presence of malignant plasma cells in the bone marrow.
Conversely, in amyloidosis, plasma cells do not accumulate. Instead, they create abnormal light chains, which lead to deposits. This can happen independently of any tumors being present. Doctors might consider amyloidosis a
There is an overlap between the two conditions, and often doctors diagnose people with both.
Some mutations in DNA may activate oncogenes — genes that promote cell growth. Other mutations may turn off tumor suppressor genes, which are genes that can slow down cell growth or cause cell death when appropriate.
Myeloma cells may also have chromosomal abnormalities. Typically, DNA fits into 46 chromosomes. Cancer cells can either have additional chromosomes or parts; sometimes the whole chromosome is missing.
For many people with this condition, parts of chromosome number 17 are missing in the myeloma cells, and this absence makes the myeloma more aggressive.
Sometimes, multiple myeloma may lead to amyloidosis.
Additionally, inflammatory diseases can cause secondary amyloidosis, and genetics can play a role in the development of hereditary amyloidosis.
Some individuals with multiple myeloma
- bone pain
- bone weakness and fractures
- spinal cord compression
- nerve damage
- low white blood cells
- low platelet counts
- high levels of calcium in the blood
An individual with amyloidosis may have some of the same symptoms, such as nerve damage.
However, they can also have issues, including:
- Heart problems: The heart can become larger and weaker, leading to fluid buildup in the lungs and shortness of breath.
- Enlarged liver: A person may be able to feel the liver below the right ribs.
- Enlarged tongue: If amyloid deposits build up in the tongue, it can increase in size leading to problems swallowing and breathing during sleep.
- Skin changes: People may bruise easily and bleed into the skin surrounding the eyes— known as raccoon eyes.
- Carpal tunnel syndrome: People may notice numbness and weakness in their hands.
Doctors diagnose multiple myeloma and amyloidosis by considering their symptoms and ordering various tests. These may include:
- Complete blood count. This test measures the level of different cells and platelets in the blood.
- Blood chemistry test. These can include checking levels of creatinine, albumin, and calcium. Creatinine shows kidney health. In multiple myeloma, doctors expect to see low albumin and may see high calcium in advanced myeloma.
- Urine test. This test measures the presence or levels of certain proteins in urine
- Quantitative immunoglobulin tests. These measure levels of antibodies in the blood.
- Electrophoresis. There are many types of this test. This test can show what types of monoclonal and other antibodies are present in the blood.
- Serum-free light chains. This test can measure the amount of light chains in the blood. This is particularly useful for diagnosing amyloidosis.
- Biopsy. Two main types include bone marrow biopsy and fine-needle aspiration biopsy.
- Imaging. These can include CT scans, bone x-rays, MRIs, and PET scans.
- Echocardiogram. This test assesses heart health, which can be important as amyloidosis often affects the heart’s structure.
A doctor may
- elevated blood calcium level
- poor kidney function
- holes in the bones from tumors
- an increase in one type of light chain with a ratio greater than 100 in the blood
- at least 60% of plasma cells in the bone marrow
Diagnosis of amyloidosis usually requires the above tests as well as other tests that look for the buildup of abnormal proteins in the body. These can include:
- fat pad biopsy,
- a kidney biopsy,
- heart biopsy,
- and special cardiac imaging.
The choice of drugs depends on the person’s health and whether the doctor plans on performing a stem cell transplant. In a stem cell transplant, an individual receives chemotherapy to kill abnormal bone marrow cells and then receives healthy blood-forming stem cells to replace them.
The doctor may also recommend treatment for bone disease, such as bisphosphonates, alongside chemotherapy. The doctor may recommend radiation therapy if individuals continue to have bone problems.
Supportive treatments such as antibiotics, transfusions to treat low blood cell counts, and intravenous immunoglobulins can be beneficial.
Individuals with multiple myeloma have a
This figure comes from people diagnosed with multiple myeloma from 2011 to 2017. Recent advances over the past several years have led to an improvement in this number.
However, a person’s outlook depends on their overall health, age, kidney function, the levels of certain substances in their blood, and the characteristics of the tumor.
If an individual has amyloidosis, their prognosis
Multiple myeloma and amyloidosis are two conditions that stem from abnormalities in the plasma cells of the bone marrow. Multiple myeloma causes an overgrowth of abnormal cells, while amyloidosis results in the secretion of abnormal proteins that can build up and damage organs.
Doctors use a similar approach to diagnose both conditions, including blood analysis, imaging studies, and bone marrow biopsies. Treatment for the conditions typically involves chemotherapy and may also involve stem cell transplant.
People with multiple myeloma have a 5-year relative survival rate of