Plasma cells are located throughout the body in bone marrow, the area at the center of the bones where new blood cells are produced. Plasma cells are a type of white blood cell that produces immune proteins called antibodies—or immunoglobulins—which help fight infection in the body. Each plasma cell divides to form other cells, all of which produce the same type of immunoglobulin as the original cell.
Multiple myeloma occurs when a plasma cell becomes malignant, multiplies uncontrollably, and produces a large amount of a single antibody, called a monoclonal protein (or gammopathy). The accumulation of this antibody in the blood is often the first sign of the disease and may damage organs in the body, such as the kidneys. In multiple myeloma, cancerous plasma cells can collect in the bones and spread to soft tissues, forming tumors called plasmacytomas.
Multiple myeloma is usually chronic, meaning people with the condition most often need ongoing treatment and support throughout their lifetime. Multiple myeloma is most common in people older than age 70. Its exact cause is not known, but certain gene mutations, or changes, seem to increase a person’s risk.
Multiple myeloma often causes no symptoms, though your general practitioner or other doctor may detect abnormal levels of antibodies in the blood and refer you to a hematologist–oncologist at NYU Langone for further testing. In addition, the increased plasma cells growing in the bone marrow can cause bone destruction, decreased normal blood cell production, and decreased normal antibody formation, leading to symptoms such as bone pain, fatigue, bleeding, and recurrent viral, bacterial, or fungal infections.
In addition to asking about your medical history and performing a physical exam, doctors at NYU Langone use a number of tests to diagnose multiple myeloma. A sophisticated analysis of blood and tissue samples provides important genetic and molecular information about the condition that can help our doctors decide which medications are most likely to be effective in your treatment. Our doctors also use the latest imaging technologies to help determine how far the disease has spread and how active it is.
Our doctors use blood tests to check for high levels of abnormal proteins released into the bloodstream by multiple myeloma cells. Checking the protein levels can help determine how advanced the disease is.
Blood tests also help detect other telltale signs of the disease, including anemia, which occurs when red blood cells are reduced in number. In people with multiple myeloma, this is due to the abnormal myeloma cells multiplying and crowding out healthy red blood cells. Doctors may check for low levels of healthy white blood cells, which can increase the risk of infection. Blood tests can also detect hypercalcemia, a high level of calcium in the blood caused by damage to bone tissue that often weakens bones. Your doctor may also check your kidneys for damage caused by myeloma proteins.
Multiple myeloma can damage the kidneys. As a result, pieces of a monoclonal protein may sometimes be found in the urine. NYU Langone doctors may run tests to look for monoclonal protein in your urine, which you usually need to collect over the span of 24 hours.
Bone Marrow Aspiration and Biopsy
If blood test results indicate the presence of multiple myeloma, your doctor may perform a bone marrow aspiration to confirm a diagnosis. In this procedure, your doctor administers a local anesthetic and uses a small needle to withdraw liquid bone marrow from the back of the pelvis. This sample is checked under a microscope for signs of cancer and tested for gene mutations. Identifying the type of mutations in the plasma cells helps your doctor verify a diagnosis of multiple myeloma, assess how aggressive the disease is, and determine what type of treatment is best.
Doctors at NYU Langone may also use bone marrow aspiration during treatment to check whether the number of myeloma cells has decreased in response to therapy.
Often performed at the same time as bone marrow aspiration, bone marrow biopsy involves the removal of a piece of bone and solid marrow from the back of the pelvis. Using a microscope, your doctor can view the bone structure and how it is affected by the growth of multiple myeloma tumors. The biopsy tissue is also tested for gene mutations to help doctors decide which type of medical therapy is most appropriate for you.
Doctors may perform a skeletal survey, in which many X-rays are taken of bones throughout the body to look for lytic lesions, areas of the bone that look lighter on the X-ray than healthy bone. These are signs of bone damage from the growth of cancerous plasma cells. This test can help determine where in the body the disease may be located.
Soon after diagnosis of multiple myeloma, your doctor may use a combination scan of PET and CT technology to look for signs of cancer in the bones and to determine the extent of bone damage. The combined scan provides one set of computer-generated, three-dimensional images. After treatment for multiple myeloma, this combined scan may be used again to tell your doctor whether a growth still contains any cancer or whether it consists of just scar tissue.
The PET scan detects cancer activity in a tumor using a small amount of radioactive glucose injected into a vein. It travels through the blood and collects in cancerous tissue, where the PET scan, using a special camera, can detect it. The CT portion of the scan uses X-rays to create cross-sectional images of the body.
MRI uses a powerful magnetic field and radio waves to produce detailed pictures of organs, soft tissues, bone, and other internal body structures. NYU Langone doctors may use an MRI in people with back pain or in those whose skeletal survey results showed abnormal areas in the bones of the spine, to see if multiple myeloma is affecting the spinal cord.
After diagnosis, your doctor may use a PET/MRI scan to take a series of three-dimensional images of the body. This scan can determine whether multiple myeloma tumors have spread outside the bone to soft tissue; it may also be used after treatment to see whether a tumor still contains cancer. The PET scan measures tumor cell activity, whereas the MRI produces detailed pictures of organs, soft tissue, and other internal body structures.
At NYU Langone, our doctors are conducting research to determine if this type of combination scan provides more information than standard PET and MRI scans.
Meet Our Doctors
Perlmutter Cancer Center specialists provide care and support during treatment.Browse Doctors