Staging, the process of finding out how much the cancer has advanced, is important for treatment options and prognosis. Prognosis is a prediction of the course of disease – the outlook for the chances of survival. It depends on the stage of the cancer. Knowing all you can about staging lets you take a more active role in making informed decisions about your treatment.

Multiple myeloma may be staged using the Durie-Salmon system. Although some doctors use this system, its value is becoming limited because of newer diagnostic methods. Recently, a new staging system called the International Staging System for Multiple Myeloma has been developed. It relies mainly on levels of albumin and beta-2-microglobulin in the blood. Other factors that may be important are kidney function, platelet count and the patient’s age.

The Durie-Salmon staging system is based on 4 factors:

The amount of abnormal monoclonal immunoglobulin in the blood or urine: Large amounts of monoclonal immunoglobulin indicate that many malignant plasma cells are present and are producing that abnormal protein.

The amount of calcium in the blood: High blood calcium levels are also related to advanced bone damage. Because bone normally contains lots of calcium, bone destruction releases calcium into the blood.

The severity of bone damage based on x-rays: Multiple areas of bone damage seen on x-rays indicate an advanced stage of multiple myeloma.

The amount of hemoglobin in the blood: Hemoglobin is the substance in red blood cells that carries oxygen. Low hemoglobin levels indicate that the myeloma cells occupy much of the bone marrow and that not enough space is left for the normal red blood cell-producing marrow cells.

There are 3 stages for the classification of the extent of the multiple myeloma. Stage I indicates the smallest amount of tumor, and stage III indicates the largest amount of tumor:

Stage I: A relatively small number of myeloma cells are found. All of the following features must be present:

• hemoglobin level only slightly below normal (above 10 grams/deciliter)
• bone x-rays appear normal or show only 1 area of bone damage
• normal blood calcium levels (less than 12 milligrams/deciliter)
• relatively small amount of monoclonal immunoglobulin in blood or urine

Stage II: A moderate number of myeloma cells are present. Features are between stage I and stage III.

Stage III: A large number of myeloma cells are found. One or more of the following features must be present:

• hemoglobin level quite low (below 8.5 g/dl)
• high blood calcium level (above 12 mg/dl)
• three or more areas of bone destroyed by the cancer
• large amount of monoclonal immunoglobulin in blood or urine

The International Staging System uses only the serum beta-2 microglobulin and serum albumin levels.

Stage I

• Serum beta-2 microglobulin is less than 3.5 (mg/L)
• Albumin is above 3.5 (g/L)

Stage II -- Neither stage I or III, meaning:

• Either 1) the beta-2 microglobulin level is between 3.5 and 5.5 regardless of the albumin level,
• or 2) the albumin is below 3.5 while the beta-2 microglobulin is less than 3.5

Stage III

• Serum beta-2 microglobulin is greater than 5.5.
• Albumin is above 3.5.

Survival rates by stage:

The approximate overall median survival for the International System stages is as follows: (median means the time that half the patients have died)

Stage	5-year survival
I	62 months
II	44 months
III	29 months

These times are taken from the time that treatment, usually chemotherapy, first started. This would exclude people with early disease such as indolent or smoldering myeloma (see below). It is important to remember that the median is just a kind of average used by researchers. No one is “average” and many people have much better outcomes than the median. Also, these patients were treated anywhere from 5 to 25 years ago. Treatment since then has improved considerably and modern results will be better.

Recurrent multiple myeloma: Recurrent disease means that the cancer has come back after treatment. Recurrent multiple myeloma may return in the bone or in another part of the body.

Smoldering myeloma and Indolent myeloma: These terms refer to people who have early myeloma that is not growing noticeably and not causing any symptoms or bone or organ damage. They are often observed very carefully without treatment.

Other Prognostic Factors

The blood creatinine level reflects the kidney's health. This chemical is eliminated from the body by the kidneys. When the kidneys are damaged by the monoclonal immunoglobulin, blood creatinine levels rise, predicting a worse prognosis. Likewise age is important. In the studies of the international staging system, older people had slightly shorter survivals.

The myeloma cell labeling index, sometimes called the plasma cell labeling index, indicates how fast the cancer cells are growing. This test is done in specialized labs, using myeloma cells from bone marrow samples. A high labeling index can predict a more rapid accumulation of cancer cells and a worse outlook.

Genetic changes such as those for chromosome 13 are also important. Changes in chromosome 13 as well as in other chromosomes will lower the chances of survival. Another genetic abnormality that predicts a poor outcome is when material from chromosomes 4 and 14 are exchanged. This is called a translocation.

Other tests may be done that do not directly examine the cancer but check the patient's general state of health and the condition of certain organs that are particularly sensitive to the side effects of certain drugs used to treat this disease. Last Revised: 08/04/2006