A diagnosis of multiple myeloma can feel overwhelming, but understanding the process can help you feel more prepared. Doctors use several tests, like blood work, bone marrow biopsies, and scans, to look for signs of the disease. These tests provide key information that helps guide your diagnosis and treatment options.

When multiple myeloma is diagnosed, it’s also assigned a stage. Knowing the stage of a multiple myeloma diagnosis provides information as to which cancer treatment options may work best.

Diagnostic Criteria for Multiple Myeloma

Traditionally, people were diagnosed with myeloma only if they had signs of organ damage, such as:

• Hypercalcemia (high calcium levels in blood)
• Decreased kidney function
• Anemia (low red blood cell count)
• Bone lesions (tumors) visible on imaging tests

Doctors diagnose multiple myeloma when a biopsy shows 10 percent or more abnormal plasma cells in the bone marrow. A biopsy is a procedure that removes a small sample of tissue for examination. Additionally, one or more of the following signs of myeloma must be present for diagnosis:

• Sixty percent or more abnormal plasma cells in the bone marrow
• High levels of abnormal light chains (proteins produced by abnormal plasma cells)
• More than one lesion visible in MRI studies
• Evidence of organ damage (high calcium levels, anemia, kidney failure, or bony lesions shown on imaging tests)

Tests and What They Show

A primary care doctor is often the first to notice signs of multiple myeloma. People visit their doctor with symptoms such as back pain, bone pain, frequent infections, or fatigue, which can be signs of myeloma. In other cases, multiple myeloma is diagnosed after blood tests for an unrelated condition reveal abnormalities, or after imaging tests for a broken bone show lesions. If your doctor suspects multiple myeloma, they will perform several tests to confirm the diagnosis and determine the extent of the cancer.

People suspected of having myeloma or a related disorder are often referred to an oncologist (cancer specialist), a hematologist (specialist in blood cancers and blood disorders), or a hematologist-oncologist (doctor with expertise in both fields). A hematopathologist, a specialist in diagnosing blood diseases, examines blood and bone marrow samples in a laboratory to provide details necessary to diagnose and stage myeloma.

Medical History and Physical Examination

Your doctor will ask detailed questions about your medical history, including any potential symptoms of multiple myeloma, such as fatigue, bone pain, or frequent infections. They may ask whether anyone in your family has ever been diagnosed with myeloma or another type of blood cell disorder. The doctor may ask about your work or hobbies to find out if you may have been exposed to chemicals or radiation, one of the risk factors for multiple myeloma.

A physical exam will allow your doctor to check for signs of anemia, bone pain, weight loss, neuropathy (pain, numbness, or tingling in the extremities), or edema (swelling).

Blood and Urine Tests

Doctors often order blood tests early on to look for signs of multiple myeloma. Blood and urine test results alone can’t diagnose multiple myeloma, but they can provide evidence that points to multiple myeloma or another condition. Blood and urine tests can reveal important information, such as:

• Anemia may suggest that cancer cells are destroying bone marrow or crowding out healthy white blood cells.
• High calcium levels could indicate that tumors are damaging the bones.
• Elevated creatinine and urea nitrogen levels may signal that the kidneys aren’t working properly.
• Albumin levels can be low in some people with myeloma.
• Elevated beta-2 microglobulin levels might suggest immune system activation or act as a tumor marker.
• Increased lactate dehydrogenase levels could point to tissue damage from cancer or another condition.
• High C-reactive protein levels may indicate inflammation in the body.

Both blood and urine tests can show whether the body is making abnormal antibodies called M proteins, monoclonal proteins, or Bence-Jones proteins. The presence of M proteins is a sign that something is wrong with the plasma cells. Tests to measure and define M protein levels include:

• Serum protein electrophoresis
• Urine protein electrophoresis
• Immunofixation electrophoresis of urine or blood
• Quantitative immunoglobulin testing
• Serum-free light chain assay (also called Freelite)

Some of these blood and urine tests also help analyze kidney function. People with myeloma often experience kidney damage due to M proteins or high calcium levels.

Bone Marrow Aspiration and Biopsy

If blood and urine test results show a strong possibility of multiple myeloma, your doctor will likely order a bone marrow aspiration and biopsy to confirm the diagnosis. These two procedures are often performed at the same time.

A bone marrow aspiration collects liquid from the bone marrow. A bone marrow biopsy takes a small piece of solid bone marrow. Both tests are done by pushing a needle into a bone, usually the back part of the hip. The doctor will numb the area first to help reduce pain.

The bone marrow sample will be studied in a lab to check how many myeloma cells myeloma cells — a type of abnormal plasma cell — are present. Doctors also do special tests, called cytogenetic studies, to look at the genes and chromosomes in the cells. These tests help doctors understand the genetic changes in myeloma cells and give a better idea of what to expect going forward.

Imaging Tests

Imaging studies are used to determine whether there are lesions or damage in the bones or soft tissues. X-rays, MRI scans, CT scans, and positron emission tomography (PET) scans may be performed to help determine how far multiple myeloma has spread.

Imaging tests are also used to create a skeletal survey. During a skeletal survey, doctors take images of all the bones in the body to look for any abnormalities.

Talk to Your Doctor

Diagnosing multiple myeloma involves a range of tests, including blood, urine, and imaging studies, as well as bone marrow biopsies. These tests help doctors identify abnormal cells, measure organ damage, and determine the stage of the cancer. Some people may also join clinical trials, which test new treatment options for multiple myeloma. Early diagnosis and knowing the stage can help guide your treatment options and support the management of multiple myeloma. If you’re experiencing symptoms or have concerns, talking to your doctor is the first step toward getting the right care.

Find Your Team

On MyMyelomaTeam, the social network for people living with multiple myeloma, members come together to ask questions, give advice, and share their stories with others who understand life with myeloma.

Have you or a loved one had symptoms like bone pain or frequent infections that might prompt testing for multiple myeloma? Share your story in the comments below, or start a conversation by posting on your Activities page.