When an individual is diagnosed with cancer, the first thing to be done is to determine which stage the cancer is at. Once that is decided, the further course of action can be charted as most of the information regarding the size, location, and extent of cancer is understood from the stage at which cancer is present. While deciding the stages of myeloma, the factor which is essentially looked at is the symptoms that are being experienced by the patients. Newly-diagnosed myeloma is classified as symptomatic (showing several signs and symptoms) or asymptomatic (not showing any signs or symptoms). The staging of multiple myeloma as explained by the Durie-Salmon system is as follows:

The Durie-Salmon Staging System
This classifies the condition of multiple myeloma into three stages: Stages I, II, and III. These three stages are further classified into subtypes A and B based on whether the kidney function has been affected or not. Type B indicated that there has been significant damage to the kidney. The three different stages of multiple myeloma as described by this system are as follows:

Stage I
In this stage, the body usually has a very low count of cancer cells, and thereby the symptoms of multiple myeloma are not shown visibly enough in this stage. If the kidney function has been affected by cancer, then the prognosis of the situation is worse no matter which stages the cancer is present. The characteristic factors which describe stage I of multiple myeloma are as follows:

• The normal amount of calcium present in the blood.
• The count of red blood cells present is either within or slightly under the normal required range.
• The levels of M protein present in the urine or blood are low:
  • M protein <5 g/dL for IgG; <3 g/dL for IgA; <4 g/24 h for urinary light chain
  • X-rays do not show any bone damage or 1 bone lesion is visible in the X-ray

Stage II
In this stage, the number of cancer cells present in the body increases significantly as when compared to the number in stage I. The prognosis would worsen significantly irrespective of the stage that the cancer is at if the kidney function has failed. Criteria for stage II counts as anything which fits neither stage I nor Stage III.

Stage III
At this stage of multiple myeloma, a high number of cancer cells are found in the body compared to the previous two stages. The characteristic features of this stage of multiple myeloma are as follows:

• Hypercalcemia
• Advanced bone damage (The X-Ray would show 3 or more bone lesions present in the body)
• Anemia occurs and hemoglobin levels in the body fall below 8.5 g/dL.
• The levels of M protein present in the blood increase significantly:
• M protein >7 g/dL for IgG; >5 g/dL for IgA; >12 g/24 h for urinary light chain

The Durie-Salmon Staging System has been the traditional method used for determining the different stages of multiple myeloma. It is still in use and is quite helpful in determining the extent of the condition and the size of the tumor.