Multiple Myeloma Treatment by Stage and Relapse

The most important sentence about myeloma staging is one NCI's PDQ summary states outright. The stage at presentation is a strong determinant of survival, but it has little influence on the choice of therapy.

PDQ gives the reason. Almost all patients have generalized disease. The exceptions are rare. They are solitary bone tumors, and extramedullary plasmacytomas. The latter is a plasma cell tumor in soft tissue, outside the marrow.

That is why a page titled "treatment by stage" has to start by explaining that myeloma does not really work that way. Stage tells a patient roughly what to expect. Risk group and transplant eligibility do the work of choosing drugs.

PDQ adds one prognostic fact that runs across all of it. Impaired kidney function worsens prognosis regardless of stage.

PDQ is explicit about the boundaries. Among plasma cell neoplasms, a staging system exists only for multiple myeloma.

Three conditions have no generally accepted staging system. Monoclonal gammopathy of undetermined significance. Isolated plasmacytoma of bone. And extramedullary plasmacytoma.

For myeloma itself, PDQ describes staging as an estimate of tumor cell mass. It uses the amount of M protein in serum or urine. It adds four clinical measures. Hemoglobin. Serum calcium. The number of lytic bone lesions. And whether kidney failure is present.

The International Myeloma Working Group built the International Staging System from a study of 11,171 patients. Of those, 2,901 received high-dose therapy. The other 8,270 received only standard-dose therapy. A separate group of 4,445 patients produced the Revised International Staging System. That version added lactate dehydrogenase levels and interphase FISH results.

These are two different systems, and it is worth keeping them apart. The original ISS rests on two blood values and nothing else:

• ISS stage I. Beta-2-microglobulin below 3.5 mg/L together with albumin at or above 3.5 g/dL.
• ISS stage II. Neither stage I nor stage III.
• ISS stage III. Beta-2-microglobulin at or above 5.5 mg/L, whatever the albumin.

The Revised system layers the genetics on top:

• R-ISS stage I. ISS stage I, with normal LDH and no high-risk FISH finding. PDQ lists median survival as not reached.
• R-ISS stage II. Neither R-ISS I nor R-ISS III. Median survival 83 months.
• R-ISS stage III. ISS stage III, plus either raised LDH or a high-risk chromosome change on FISH. Median survival 43 months.

PDQ presents these survival figures in a single table headed as the ISS, although the criteria in it are the Revised ones. If you are given a stage number, ask which of the two systems it came from.

PDQ defines those high-risk chromosome changes precisely: del(17p), translocation t(4;14), or translocation t(14;16).

PDQ's risk grouping comes from genetic changes found on interphase FISH, and it maps to survival ranges rather than to stages.

Good risk covers no adverse FISH or cytogenetic findings, hyperdiploidy, t(11;14), or t(6;14). PDQ notes these patients most often have IgG kappa disease and lytic bone lesions. Median survival is 10 to 12 years.

Intermediate risk covers t(4;14) and t(14;16). PDQ describes these as once-harmful features that standard triplet or quadruplet regimens have blunted. These patients often have IgA lambda disease, and less bone involvement. Median survival is 5 to 10 years.

High risk covers a longer list. Del 17p. T(14;16). T(4;14). T(14;20). Del 13. Biallelic deletion of TP53. Gains and amplifications of 1q. And deletions of 1p32. Plasma cell leukemia sits here too. Median survival is under 5 years, and under 3 years for the ultra-high-risk subset.

Two cautions come attached. PDQ says this stratification is derived from retrospective analyses and requires prospective validation. And it notes that the otherwise favorable prognosis of hyperploidy is trumped by coexisting adverse cytogenetics.

PDQ also singles out plasma cell leukemia, defined as more than 2% to 5% circulating plasma cells, as carrying a particularly poor prognosis.

PDQ states that patients with MGUS or asymptomatic smoldering myeloma do not require immediate treatment, but must be followed carefully for signs of progression.

It calls out the difficulty directly. The major challenge is separating two groups. One is stable and needs no treatment. The other has progressive, symptomatic disease and may need treatment at once.

One number helps with that. PDQ says a free light chain ratio over 100 can predict greater than 70% progression within 2 years in smoldering myeloma. Where that same ratio is used to call the disease active rather than smoldering, the IMWG criterion is stricter: the involved-to-uninvolved ratio must be 100 or more and the involved light chain itself must measure at least 100 mg/L. Ask for both figures, not just the ratio.

PDQ includes a practical warning about the number people watch most.

M protein can be measured by serum electrophoresis, or by specific immunoglobulin assays. But the immunoglobulin assay always overestimates the M protein. The reason is that normal immunoglobulins get counted in the result.

Because of that, PDQ says the preference is often for baseline and follow-up measurements to be done by the same method.

That is a real reason a number can appear to jump between visits without the disease changing. Asking which assay produced a result is a fair question.

Quantitative serum free light chains, PDQ adds, may help follow response when no M protein is apparent.

Since stage does not choose therapy, two other things do.

The first is transplant eligibility. PDQ notes that alkylating drugs such as melphalan are avoided upfront in transplant-eligible patients. The reason is specific. They are toxic to stem cells. That brings later risks of low blood counts, second cancers, or a poor stem cell harvest.

The second is risk group. After a transplant using a person's own stem cells, PDQ says lenalidomide maintenance is offered. The basis is steady gains in time before growth, and occasional gains in survival. For high-risk disease, especially del(17p) or t(14;16), PDQ says bortezomib maintenance may be required. Then it states plainly that this approach is not evidence-based, and needs confirmatory trials.

Two supportive details follow from the regimens rather than the stage. PDQ says bortezomib is given under the skin to avoid the more severe nerve damage seen with intravenous dosing, and is preferred when kidney function is impaired. And it says patients on a bortezomib regimen need protection against herpes zoster. The usual drugs are valacyclovir or acyclovir.

Myeloma damages bone, kidneys, and the immune system, and the drugs above add their own risks. Three things should not wait.

• Call 911 or go to an emergency department if you have new weakness in your legs, numbness that spreads across both legs, or you lose control of your bladder or bowel, especially with back pain. That combination can mean the spinal cord is being compressed, and outcomes are much better when it is treated within hours rather than days.
• Treat a fever on treatment as an emergency. CDC says a temperature of 100.4°F (38°C) or higher during chemotherapy is a medical emergency and to call your doctor immediately; shaking chills count too. If your team cannot be reached at once, go to an emergency department. Myeloma and its treatment both lower defences against infection.
• Call your care team the same day if you become confused, very thirsty, or are passing urine far more often, with nausea, vomiting, constipation, or muscle weakness. NCI lists these as effects of a high blood calcium level, which myeloma can cause.
• Call your care team the same day if you are passing much less urine than usual, or your ankles swell quickly. Kidney function can fall fast in myeloma.
• Call your care team within a day or two if you have new back or rib pain, or pain after a small knock. Weakened bone can break under everyday load.
• Call your care team within a day or two if a painful rash or blistering appears in a band on one side of the body while you are on a bortezomib regimen. That is the shingles risk the preventive valacyclovir or acyclovir is there to cover.
• Call your care team within a day or two if numbness, tingling, or burning in the hands or feet is new or getting worse. Bortezomib causes nerve damage, and dose or route can be changed.

The disease itself is described in multiple myeloma. The precursor conditions are covered in smoldering myeloma and MGUS. The staging vocabulary is expanded in multiple myeloma staging.

• NCI PDQ: plasma cell neoplasms, HP version
• NCI PDQ: plasma cell neoplasms, patient version, accessed August 11, 2026
• StatPearls (NCBI Bookshelf) — Metastatic Spinal Cord Compression, accessed August 11, 2026
• StatPearls (NCBI Bookshelf) — Neutropenic Fever, accessed August 11, 2026
• CDC — Fever and Cancer Treatment, accessed August 13, 2026