Symptoms depend on where the tumor is.
- In bone, the plasmacytoma may cause pain or broken bones.
- In soft tissue, the tumor may press on nearby areas and cause pain or other problems. For example, a plasmacytoma in the throat can make it hard to swallow.
In multiple myeloma, abnormal plasma cells (myeloma cells) build up in the bone marrow and form tumors in many bones of the body. These tumors may keep the bone marrow from making enough healthy blood cells. Normally, the bone marrow makes stem cells (immature cells) that become three types of mature blood cells:
- Red blood cells that carry oxygen and other substances to all tissues of the body.
- White blood cells that fight infection and disease.
- Platelets that form blood clots to help prevent bleeding.
As the number of myeloma cells increases, fewer red blood cells, white blood cells, and platelets are made. The myeloma cells also damage and weaken the bone.
Sometimes multiple myeloma does not cause any symptoms and is found when a blood or urine test is done for another condition. The following symptoms may be caused by multiple myeloma or other conditions. Check with your doctor if you have any of the following problems:
- Bone pain, especially in the back or ribs.
- Bones that break easily.
- Fever for no known reason or frequent infections.
- Easy bruising or bleeding.
- Trouble breathing.
- Weakness of the arms or legs.
- Feeling very tired.
A tumor can damage the bone and cause hypercalcemia (too much calcium in the blood). This can affect many organs in the body, including the kidneys, nerves, heart, muscles, and digestive tract, and cause serious health problems.
Hypercalcemia may cause the following symptoms:
- Loss of appetite.
- Nausea or vomiting.
- Feeling thirsty.
- Frequent urination.
- Feeling very tired.
- Muscle weakness.
- Confusion or trouble thinking.
Multiple myeloma and other plasma cell neoplasms may cause a condition called amyloidosis.
In rare cases, multiple myeloma can cause peripheral nerves (nerves that are not in the brain or spinal cord) and organs to fail. This may be caused by a condition called amyloidosis. Antibody proteins build up and stick together in peripheral nerves and organs, such as the kidney and heart. This can cause the nerves and organs to become stiff and unable to work the way they should.