The Stages of Multiple Myeloma
Staging is part of diagnosing cancer, including multiple myeloma. Traditionally, this process involves finding out if the cancer has spread and if so, how extensively. It tells your doctor how advanced the cancer is. For multiple myeloma, your doctor will likely order imaging exams to determine the extent of cancer. However, blood tests and genetic tests are an important part of staging this cancer.
Over the years, there have been various ways to stage multiple myeloma. Today, doctors commonly use a system called the Revised International Staging System. This system uses four factors to determine multiple myeloma stages:
Albumin blood levels: Low levels can indicate advanced disease.
Beta-2 microglobulin blood levels: High levels indicate advanced disease.
Gene changes, or the cytogenetics of the cancer cells: Gene analysis is either standard or high risk.
LDH (lactate dehydrogenase) blood levels: High levels indicate a poorer prognosis.
Based on this information, doctors classify multiple myeloma into three stages using Roman numerals: I, II and III. The higher the number, the more severe the disease. Unlike many other cancers, stage is not the main element in planning treatment. Instead, doctors decide how and when to treat multiple myeloma based on symptoms and organ function. Identifying the clinical stage is most helpful in directing patients to the most effective treatment strategies, including clinical investigative trials.
Once treatment starts, it consists of three phases—induction therapy, consolidation therapy, and maintenance therapy. Chemotherapy is the main treatment for multiple myeloma, along with targeted therapy and stem cell transplants.
Staging also gives your doctor information about your prognosis. Traditionally, when discussing cancer prognosis, it’s common to use a 5-year survival rate. This number is the percentage of people treated five years ago who are still alive today. However, doctors talk about survival with multiple myeloma as median survival. In multiple myeloma, this number represents how long the first half of the people with the disease lived after treatment began. Half the people lived longer than this number.
Median survival is an estimate or guideline for prognosis based on stage. Keep in mind that people can die of other causes. And treatments are always evolving. Moreover, there are other factors that influence survival. This includes your kidney function, overall health, and age. (The average age at diagnosis is 70 years.) Your doctor is the best resource for information about your prognosis.
Criteria for stage I multiple myeloma:
Albumin level is 3.5 g/dL or higher, which is normal.
Beta-2 microglobulin level is less than 3.5 mg/L, which is the cutoff.
Cytogenetics is standard, or not high risk.
LDH levels are normal.
Median survival at this stage is 62 months, or more than five years.
Stage II criteria is somewhere between stage I and stage III. Sometimes, doctors classify stage II as “not stage I or III.” In general, either of these criteria can bump multiple myeloma from stage I to stage II:
Albumin level is less than 3.5 g/dL, which is low.
Beta-2 microglobulin level is between 3.5 mg/L and 5.5 mg/L.
Median survival for stage II is nearly four years.
Stage III multiple myeloma cancers are advanced. For stage III, the beta-2 microglobulin level is 5.5 mg/L or higher, along with either of the following:
Cytogenetics is high risk.
LDH levels are high.
With stage III multiple myeloma, median survival is almost two years.
Multiple myeloma staging is important because it helps your doctor understand the severity of your disease. This can give your doctor an idea of how long you may need treatment. Discuss your treatment options with your doctor. Talk about the possibility of a clinical trial to see if you are a good candidate. A clinical trial can give you access to the newest treatments that may not be available any other way.