Newly Diagnosed With Multiple Myeloma: First Steps

Myeloma is a cancer of plasma cells, the bone marrow cells that normally make antibodies. Diagnosis is not a matter of opinion. It turns on defined events.

The classic four are called CRAB. NCI gives the thresholds:

• C, calcium. Serum calcium more than 1 mg/dL above the upper limit of normal.
• R, renal. Creatinine above 2 mg/dL, or creatinine clearance below 40 mL/min.
• A, anemia. Hemoglobin below 10.0 g/dL.
• B, bone. One or more lytic lesions, meaning holes eaten into bone, seen on imaging.

Three more count as myeloma-defining events, known as the SLiM criteria:

• Clonal plasma cells making up 60% or more of the marrow.
• An involved to uninvolved serum free light chain ratio of 100 or more.
• More than one focal lesion of at least 5 mm on spinal MRI.

Any one of these seven means active myeloma. Ask which of them you have. The answer shapes urgency.

Many people arrive here from an abnormal blood test rather than symptoms. Where you sit matters enormously.

MGUS. Monoclonal gammopathy of undetermined significance. An M protein is present, but fewer than 10% of marrow cells are plasma cells, and there are no myeloma features. NCI puts the annual progression rate at 0.5% to 1.0% in population studies, rising to 2% or more than 20% in higher-risk groups.

Smoldering myeloma. NCI's criteria are a serum M protein of 30 g/L or more, or urine M protein of 500 mg or more per 24 hours, together with clonal marrow plasma cells of 10% to 60%, and no myeloma-defining events.

High-risk smoldering. NCI describes a 2/20/20 rule. Three or four of these adverse factors predict more than 50% progression within 2 years: M protein above 2 g/dL, free light chain ratio above 20, marrow plasma cells above 20%, and adverse cytogenetics such as t(4;14), t(14;16), 1q gain, or del13.

Active myeloma. Any CRAB or SLiM event is present.

NCI's workup list is specific. Check your chart against it:

• Serum and urine protein electrophoresis.
• Immunofixation electrophoresis, to identify the heavy and light chain type.
• Serum free light chain quantification and ratio.
• Bone marrow biopsy with FISH cytogenetics.
• Complete blood count and metabolic panel.
• Creatinine clearance.
• Skeletal survey, and if that is negative, spinal MRI, spinal CT, or PET-CT.
• Beta-2-microglobulin and serum albumin.

If FISH cytogenetics is missing, ask for it. It drives more decisions than almost anything else on this list.

There is no tumor to measure, so myeloma uses the Revised International Staging System. NCI gives the criteria and the median survival attached to each:

• R-ISS I — beta-2-microglobulin under 3.5 mg/L and albumin 3.5 g/dL or above. Median survival not reached.
• R-ISS II — everything in between. Median survival 83 months.
• R-ISS III — beta-2-microglobulin 5.5 mg/L or above, plus either high LDH or high-risk cytogenetics such as del(17p), t(4;14), or t(14;16). Median survival 43 months.

NCI groups patients by FISH findings, with very different outlooks:

• Good risk, with a 10 to 12 year median survival. No adverse FISH findings, hyperdiploidy, t(11;14), or t(6;14).
• Intermediate risk, 5 to 10 years. t(4;14) or t(14;16). NCI notes modern triplet and quadruplet regimens have blunted the effect these once had.
• High risk, under 5 years. del(17p), t(14;16), t(4;14), t(14;20), del(13), gain of 1q with 3 or more copies, or amplification with 4 or more.
• Ultra-high risk, under 3 years. Biallelic del(TP53) or biallelic del(1p32).

Ask for your FISH panel result by name, not as "the genetics were fine."

The standard backbone is VRd, meaning bortezomib, lenalidomide, and dexamethasone. The question now is whether an antibody joins it.

The FDA approved daratumumab and hyaluronidase-fihj with bortezomib, lenalidomide, and dexamethasone for newly diagnosed multiple myeloma in people who are not eligible for an autologous stem cell transplant.

The evidence came from CEPHEUS, which randomized 395 patients: 197 to the four-drug regimen and 198 to VRd alone. The hazard ratio for progression-free survival was 0.60, with a 95% confidence interval of 0.41 to 0.88. The rate of minimal residual disease negativity was 52.3% against 34.8%.

The recommended dose is 1,800 mg of daratumumab with 30,000 units of hyaluronidase, given under the skin.

That approval is written for transplant-ineligible patients. So the first question at your visit is which group you are in, and who decides.

Notice that CEPHEUS reported MRD negativity as a headline result. That reflects a regulatory shift.

The FDA's guidance on myeloma states MRD negativity should be assessed at a threshold of at least 1 in 100,000 residual tumor cells, using flow cytometry or sequencing, on a bone marrow aspirate. It also records that its advisory committee agreed MRD is acceptable as an endpoint supporting accelerated approval.

Expect the term to come up. It is explained further in our page on measurable residual disease.

SEER lists 36,000 new myeloma cases and 10,850 deaths in the United States for 2026, a projection made by the American Cancer Society. Most diagnoses fall between ages 65 and 74. About 0.8% of people will be diagnosed with myeloma at some point in life.

Five-year relative survival is 63.7% for 2016 through 2022. Note that SEER classifies 96% of myeloma as distant disease, so its stage-by-stage survival split carries little meaning here.

The more useful comparison is over time. NCI reports median survival of about 7 months before chemotherapy existed, then 24 to 30 months once chemotherapy arrived, and now medians exceeding 10 years.

Go to an emergency department for:

• New back pain with weakness or numbness in the legs, or loss of bladder or bowel control. Bone lesions can weaken the spine, and this pattern needs imaging the same day.
• Confusion, severe thirst, or heavy vomiting, which can signal a high calcium level.
• Passing much less urine than usual.
• Sudden shortness of breath or chest pain.

Call the myeloma team the same day for:

• A temperature of 100.4 °F (38 °C) or higher, the threshold CDC gives during cancer treatment.
• A new bone pain that stops you bearing weight.
• Numbness or burning in the hands or feet during bortezomib treatment.

• Is this MGUS, smoldering myeloma, or active myeloma, and which criterion decided it?
• What is my R-ISS stage, and what did FISH cytogenetics show?
• Am I considered transplant-eligible, and who makes that call?
• Which induction regimen is planned, and is daratumumab part of it?
• Is a bone-strengthening drug being started, and when?
• Will MRD be measured, and at what sensitivity?

Multiple Myeloma is the full overview. What Does Minimal Residual Disease Mean? explains the testing above. Getting a Second Opinion is worth considering before induction starts.

• NCI PDQ — Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (Health Professional Version)
• NCI SEER — Cancer Stat Facts: Myeloma
• U.S. Food and Drug Administration — FDA approves daratumumab and hyaluronidase-fihj with bortezomib, lenalidomide, and dexamethasone for newly diagnosed multiple myeloma
• U.S. Food and Drug Administration — Minimal Residual Disease and Complete Response in Multiple Myeloma: Use as Endpoints to Support Accelerated Approval
• National Cancer Institute — Infection and Neutropenia during Cancer Treatment
• American Cancer Society — Cancer Facts & Statistics