Although multiple myeloma primarily attacks the bones, its effects on bone marrow and the immune system can cause a wide variety of symptoms throughout the body. In some people, multiple myeloma can lead to dangerous complications involving the kidneys and blood vessels.
For some people, early symptoms of multiple myeloma can include back pain, bone pain, fatigue, nausea, or severe infection. Other people with myeloma may not notice that anything is wrong until a bone fractures or kidney function is affected. For about 30 percent of people, multiple myeloma is asymptomatic (without symptoms) at diagnosis. In these cases, multiple myeloma is usually detected during blood tests for unrelated health issues.
Not everyone with multiple myeloma will experience every possible myeloma symptom. What symptoms someone experiences may depend on what type of myeloma (or related condition) they have. Many symptoms of myeloma can be managed with effective treatment.
In multiple myeloma, abnormal white blood cells form bone tumors (also called lesions) that can cause bone pain. Pain in the back, skull, hips, and ribs is common in those with myeloma. Myeloma lesions also weaken bone and can lead to fractures. Broken bones often take longer to heal in people with myeloma, so fractures hurt for longer. Some types of fractures, including hip fractures, often lead to chronic pain. Bone lesions in the vertebrae can cause the spine to collapse, compressing the spinal cord and causing nerve pain. Persistent headaches, muscle pain, and abdominal pain can also be symptoms of myeloma.
Myeloma treatments can damage nerves, leading to neuropathy — pain, tingling, burning, or numbness, often in the extremities. Neuropathy caused by chemotherapy or other myeloma treatments may persist for months after treatment ends. In some people, it is permanent.
Multiple myeloma compromises the immune system by reducing the number of healthy white blood cells that fight infection. Myeloma treatments can further reduce levels of effective white blood cells and suppress the immune system in other ways. People with myeloma are vulnerable to infections by bacteria, viruses, and fungi that would be easily fended off by those with healthy immune systems. Common colds and the flu can be more severe in those with myeloma. Fevers are common in people with myeloma as their immune systems struggle to fight infections.
Many people with multiple myeloma develop anemia (low levels of red blood cells) as myeloma cells crowd the bone marrow where red blood cells are produced. Some myeloma treatments further damage the bone marrow, worsening anemia. Red blood cells are responsible for carrying oxygen, which is needed by the body to produce energy. In people with anemia, fatigue can be severe. Myeloma also causes changes to the immune system that can contribute to fatigue.
As multiple myeloma destroys bone, large amounts of calcium are released into the bloodstream. Hypercalcemia is the term for higher-than-normal levels of calcium in the blood. Hypercalcemia can cause muscle weakness and drowsiness.
Fractures in the vertebrae can cause the spine to collapse, resulting in changes to posture. Advanced myeloma can cause a pronounced stoop and a loss of height. People with bone lesions in the hips may lose mobility as it becomes painful to walk.
Some people with myeloma experience cognitive symptoms, such as memory problems, trouble concentrating, slurring of words, and getting lost in familiar places. Neurological symptoms may be caused by chemotherapy, known as “chemo brain” or “cog fog.” Cognitive issues can also be caused directly by myeloma, as a result of high levels of calcium or abnormal proteins in the blood that interfere with blood flow in the brain. In some cases, people with myeloma may experience seizures or weakness on one side of the body.
Hypercalcemia and dehydration can lead to constipation. Kidney damage may cause dehydration, worsening constipation. Many myeloma treatments cause gastrointestinal side effects, such as nausea, vomiting, diarrhea, constipation, and abdominal pain. Some treatments can cause sores in the mouth. In many people, gastrointestinal symptoms and side effects may result in weight loss. Other medications, such as corticosteroids, may cause weight gain.
Myeloma treatments can cause skin problems, such as rashes, itching, blisters, bruising around the eyes, and changes in skin color or texture. Some chemotherapy medications can damage the skin at the site where they are injected.
Edema (swelling) in the face, ankles, legs, and abdomen is rare in those with multiple myeloma. Many people with myeloma experience anxiety and depression, which are common symptoms for all people living with chronic illnesses.
In multiple myeloma, cancer cells secrete large quantities of antibodies — proteins produced by the immune system to protect against infection. Myeloma produces antibodies that are abnormal and ineffective. High levels of calcium in the blood can also contribute to drowsiness and kidney damage.
More than 50 percent of people with multiple myeloma experience problems with kidney function. About 10 percent of people with multiple myeloma develop kidney failure severe enough to require kidney replacement therapy, such as dialysis. Symptoms of kidney problems include an increase or decrease in urination, intense thirst, weakness, and abdominal pain.
Platelets are fragments of blood cells that play a major role in forming blood clots. In some people with myeloma, damage to bone marrow lowers the number of platelets, leading to abnormal bleeding — nosebleeds, bleeding from the gums, and bruising easily.