What is Multiple Myeloma?
Multiple myeloma (MM) is cancer of plasma cells. Plasma cells are a type of differentiated B cell that originate in the bone marrow. In the body, plasma cells have an important role in producing antibodies to defend against infections.1 Plasma cells in normal bone marrow versus in multiple myeloma are depicted in the figure.
When plasma cells grow uncontrollably—as happens in multiple myeloma, they crowd out healthy bone marrow cells. This can lead to other conditions, including anemia, bleeding disorders, infections, and bone lesions. In most patients with multiple myeloma, the abnormal plasma cells produce an unusual non-functional type of antibody called monoclonal protein, which can contribute to disease progression.3
Who is affected by myeloma?
In the United States , more than 36,000 new diagnoses of multiple myeloma are expected each year, along with more than 12,000 multiple myeloma-associated deaths.4
There are several factors that can contribute to the risk for developing multiple myeloma, including older age (average age at the time of diagnosis is approximately 70).5 Men are more likely to develop multiple myeloma than women, and Black people are twice as likely to develop multiple myeloma as White people.5 Having a family member with myeloma can also increase your risk.5 Some evidence suggests that being overweight or obese may increase risk, as well as certain underlying conditions such as pernicious anemia or ankylosing spondylitis.6,7 Risk factors for multiple myeloma are shown in the figure.
There may also be some occupational risk for the development of multiple myeloma, particularly with jobs that involve exposure to chemicals and other hazardous substances.7
References
- Syeda MZ, Hong T, Huang C, Huang W, Mu Q. B cell memory: From generation to reactivation: A multipronged defense wall against pathogens. Cell Death Discov. 2024;10:117.
- National Cancer Institute. NCI Dictionary of Cancer Terms. https://www.cancer.gov/publications/dictionaries/cancer-terms/def/multiple-myeloma
- National Comprehensive Cancer Network®. NCCN Guidelines for Patients. Multiple Myeloma, 2026. https://www.nccn.org/patients/guidelines/content/PDF/myeloma-patient.pdf
Siegel RL, Kratzer TB, Giaquinto AN, et al. Cancer statistics, 2025. CA Cancer J Clin. 2025;75:10-45.
- Padala SA, Barsouk A, Barsouk A, et al. Epidemiology, staging, and management of multiple myeloma. Med Sci. 2021;9:3.
- Went M, Cornish AJ, Law PJ, et al. Search for multiple myeloma risk factors using Mendelian randomization. Blood Adv. 2020;4:2172-2179.
- Sergentanis TN, Zagouri F, Tsilimidos G, et al. Risk factors for multiple myeloma: A systematic review of meta-analyses. Clin Lymphoma Myeloma Leuk. 2015;15:563-577.e1-3.
- Basavatarakam Indo American Cancer Hospital & Research Institute. Multiple myeloma: Causes, symptoms, diagnosis, and treatment – Indo American Hospital, Hyderabad. 2023. https://induscancer.com/multiple-myeloma-causes-symptoms-diagnosis-and-treatment-basavatarakam-indo-american-cancer-hospital/
ALL URLs accessed April 18, 2026
