It is difficult to diagnose multiple myeloma early. In many patients multiple myeloma may not cause symptoms until after it has reached an advanced stage. In other patients, it may cause vague symptoms that at first appear to be due to other diseases. Or it may be found on a routine blood test where an abnormally high amount of protein is found in the blood.

Symptoms of Multiple Myeloma

Although some patients with multiple myeloma have no symptoms at all, the following are the most common symptoms of this disease:

Bone pain: Bone is formed by cells called osteoblasts and dissolved by cells called osteoclasts. Plasma cell tumors can release substances that activate the bone-absorbing osteoclasts and may block the bone-producing osteoblasts. This can cause areas of bone weakness that are painful. These changes increase the chance that the bones will break, even with minor stress or injury. Any bone may be affected, but pain over the backbone, hip bones, and skull is particularly common.

Symptoms of blood problems: When myeloma cells replace the normal blood-forming marrow cells, shortages of red blood cells, white blood cells, and blood platelets result. A reduced amount of red blood cells, a condition called anemia, causes weakness, reduced ability to exercise, shortness of breath, and dizziness. Too few white blood cells (a condition called leukopenia) lowers resistance to infections such as pneumonia. When blood platelet counts are low (a condition called thrombocytopenia), even minor scrapes, cuts, or bruises may cause serious bleeding.

Nervous system symptoms: Weakness and collapse of spinal bones can compress important nerves, causing severe pain, numbness, and/or muscle weakness. This is a medical emergency and your doctor must be notified as soon as possible. As the minerals from damaged bone are absorbed, the blood calcium levels rise (hypercalcemia). Because calcium affects nerve cell function, too much of this mineral in the blood can cause weakness and mental confusion.

Sometimes, the abnormal proteins produced by myeloma cells can be damaging to nerves, causing weakness and numbness. In some patients, large amounts of abnormal myeloma protein can cause the blood to "thicken." This can slow circulation to the brain and cause mental confusion, dizziness, and stroke-like symptoms. Patients with these symptoms should call their doctor. Removing the protein from the blood by a procedure called plasmapheresis can rapidly reverse this problem.

Kidney symptoms: The abnormal amount of myeloma protein can damage the kidneys. This reduces a person's ability to dispose of excess salt, fluid, and body waste products. People with kidney failure usually experience weakness and leg swelling.

High blood calcium: Sometimes the myeloma causes bones to dissolve so quickly that large amounts of calcium are released into the blood (hypercalcemia). This can cause the kidneys to fail. One symptom is being very thirsty and feeling dry. Others are loss of appetite, feeling drowsy or sleepy, and constipation.

Infections: Myeloma patients are about 15 times more likely to develop infections. The most common and serious of these is pneumonia. This happens because the body is unable to make the antibodies that help fight infection.

Source: American Cancer Society