This summer I am sharing guest blogs from a variety of experts. This week’s blog is the third in a multi-part series about multiple myeloma from my colleague Dr. Margaret Henderson who has a Doctor of Pharmacy degree from the University of Colorado.
–Dr. Stephen Vogt
Welcome to the third installment in a 5-part patient education series on multiple myeloma. Multiple myeloma, a form of cancer affecting the bone marrow, is diagnosed in approximately 30,000 Americans each year. In this disease, malignant plasma cells (which are a type of white blood cell) start growing out of control and can create multiple tumors in the bones. The cancerous plasma cells can also crowd out other cells in the bone marrow, leading to lower blood counts and anemia.
STAGING AND PROGNOSIS
Staging of multiple myeloma means determining how much the cancer has advanced. While prognosis is a prediction of the course of disease, or in other words, the outlook for survival.
Durie-Salmon Staging System: This system is based on the amount of abnormal M-proteins present in the blood or urine, the amount of calcium in the blood, the severity of bone damage based on x-ray, and the amount of hemoglobin in the blood.
- Stage I – Relatively small number of myeloma cells are found and all of the following features must be present:
- Hemoglobin is slightly lower than normal, but still above 10 g/dL;
- Bone x-rays appear normal or only show one area of bone damage;
- Calcium levels are normal; and
- Only a relatively small amount of M-proteins found in blood or urine
- Stage II – A moderate number of myeloma cells are present, and patient does not meet criteria for Stage I or Stage III
- Stage III – A large number of myeloma cells are found and one or more of the following must be present:
- Hemoglobin levels below 8.5 g/dL;
- Blood calcium levels above 12 mg/dL;
- Cancer has caused three or more areas of bone destruction; and/or
- A large amount of M-proteins found in the blood or urine
International Staging System for Multiple Myeloma: Basis for staging is serum beta-2 microglobulin (Reference Values: 1.21 to 2.70 mg/L) and serum albumin levels (Reference Values 3.5 to 5.5 g/dL).
- Stage I – Serum beta-2 microglobulin <3.5 mg/L and albumin >3.5 g/dL
- Median survival is 62 months
- Stage II – Patient does not meet criteria for Stage I or Stage III
- Serum beta-2 microglobulin is between 3.5 mg/L and 5.5 mg/L OR
- Albumin <3.5 g/dL and serum beta-2 microglobulin <3.5 mg/L
- Median survival is 44 months
- Stage III – Serum beta-2 microglobulin >5.5 mg/L
- Median survival is 29 months
Genetic Risk Stratification (Mutagenicity): Patients with newly diagnosed multiple myeloma undergo genetic testing to help determine their prognosis, which estimates their survival time. Myeloma cells may present with cytogenetic abnormalities, which may make the disease more virulent.
- High Risk Disease – Very aggressive and may shorten survival. It is characterized by cytogenetic abnormalities of 17p13 deletion, translocation at (14;16), translocation at (14;20), serum levels of lactate dehydrogenase (LDH) ≥2 times institutional upper limit of normal, features of primary plasma cell leukemia, high-risk gene expression profiling signature.
- Intermediate Risk Disease – This was previously considered to be high-risk disease, but with appropriate therapy, patient have outcomes approaching that of standard-risk multiple myeloma. It is characterized by cytogenetic abnormalities of 1q gain, deletion 13, translocation at (4;14), hyperdiploidy by conventional karyotyping.
- Standard or Low Risk Disease – Patients who lack high- or intermediate-risk genetic abnormalities are considered to have standard-risk multiple myeloma and have an estimated median survival of 8 to 10 years.
- Kidney function – Patients with normal kidney function have a better prognosis than those with underlying kidney disease.
- Age – Younger patients tend to live longer than older patients.
- Labeling index – This indicates how fast the cancer cells are growing. Patients with a high labeling index have a more rapid accumulation of cancer cells, and a worse prognosis.
GOALS OF TREATMENT
At the present time, multiple myeloma is not curable. The goal of therapy is to control the disease (which is also referred to as remission) and reverse and/or prevent the complications that are related to the disease itself. However, with the advent of new therapies, the goals of therapy may change from controlling the disease to curing the disease. Additional research in the realm of combination therapy, treatment timing (using specific treatments in a specific order for maximal benefit), and the advent of newer and more effective therapies are needed to find a cure for this disease.
The following weeks of this 5-part series will focus on specific treatment choices and treatment complications.
‘How Is Multiple Myeloma Staged?’ The American Cancer Society, The American Cancer Society, http://www.cancer.org