Multiple myeloma is a cancer in which white blood cells called plasma cells develop abnormalities and damage the bone marrow. Many risk factors are believed to play a role in the cause of myeloma, although it’s not fully understood yet why some people get myeloma and some don’t.

Race appears to be a significant risk factor for myeloma. Black Americans are twice as likely to be diagnosed with multiple myeloma as white Americans. Hispanic people have a slightly lower risk of multiple myeloma than white people. Those of Asian descent appear the least likely to be diagnosed.

The reasons behind these racial disparities are not yet fully understood, and more research is needed. Learn more about how race may impact who gets myeloma, how it is treated, and survival rates.

Risk Factors for Multiple Myeloma

Many risk factors have been suggested for multiple myeloma, including:

• Having a family history of multiple myeloma
• Having Black ancestry
• Being exposed to chemicals, pesticides, or radiation
• Smoking tobacco
• Being obese
• Using alcohol
• Having anemia (low red blood cell count)
• Being diagnosed with ankylosing spondylitis

Multiple myeloma is always preceded by monoclonal gammopathy of undetermined significance (MGUS). MGUS is an early, asymptomatic blood disorder that develops into multiple myeloma in some people. It can be considered a risk factor for myeloma. In the United States, the prevalence of MGUS is significantly higher in Black people than white people, especially at younger ages.

We don’t yet know exactly what causes multiple myeloma. While race and genetics appear to play a role, the mechanisms are not clear. What seems most likely is that multiple myeloma is caused by many different factors.

Are Genetics a Factor?

Race appears to be a factor affecting risk of multiple myeloma. Studies of people with African heritage from multiple countries consistently show Black people to be at increased risk for multiple myeloma, suggesting that the disparity is not exclusive to Black Americans. This may suggest a genetic component to risk, although it has yet to be proved.

Family Risk Is Higher for Black People

To some extent, multiple myeloma does appear to be heritable (passed down from parents), with clusters of cases appearing within families. Multiple studies show that Black people with a family history of multiple myeloma have an even higher risk than white people with multiple myeloma in their family history. Why multiple myeloma appears more heritable for Black families is not known. Initial genetic research is identifying genetic markers of multiple myeloma that appear unique to Black people. However, because Black people are underrepresented in cancer genomics research, the ability to draw conclusions is limited.

Questions About Genetics and Race

It’s important to note that genetics and disease heritability might not be correlated with race at all. Diseases like sickle cell anemia, for example, might be better thought of as tied to a specific place of ancestry, not race. Not all African countries have the same rates of sickle cell anemia. The phenomenon is specific to West-Central Africa and parts of India, the Arabian Peninsula, and the Mediterranean — not to Black people in general.

This finding, along with recent studies in genetic science, suggests that looking for genetic links between disease and race may be a faulty premise.

Disparities in Treatment and Outcome

Some studies show that Black people are diagnosed with multiple myeloma at a younger age. A few studies show Hispanic people to be more likely to be diagnosed with multiple myeloma at a younger age than white people. The reasons for younger diagnosis, and how it may affect outcomes, are unclear.

Race and Access to Treatment

In the United States, Black people with multiple myeloma have shorter life spans than white people with multiple myeloma. They also are less likely to receive the latest treatments for multiple myeloma, like stem cell transplants (also known as bone marrow transplants).

Exactly why Black people do not access the latest treatments as often as white people is not known. There may be many factors affecting this, including disparities in health insurance and access to primary care providers. Regardless of the root causes, it is likely that disparities in access to treatment directly affect the longevity of Black Americans with multiple myeloma.

Hispanic people also appear to have less access to newer treatments. It’s important to note that Hispanic people have been the least studied ethnic population within multiple myeloma research, so even less is known about differences in disease diagnosis and outcomes in this population.

Race and Overall Survival

Thanks to new treatments, the five-year relative survival rate for multiple myeloma has risen from 35 percent in 2000 to 50 percent in 2020. Five-year relative survival rates are similar between Black (53.9 percent) and white (51.3 percent) Americans as well.

However, other measures of survival show potential differences between races. When Black and white Americans undergo the same treatments for multiple myeloma, Black people may have higher rates of survival compared with white people. Also, Black people are less likely than white people to have certain high-risk mutations (including TP53) on their cancer cells. These mutations are associated with a worse prognosis.

More Research Is Needed

People of color are underrepresented in oncology research, including clinical trials and trials for new treatments. In fact, African American enrollment in clinical trials dropped between 1992 and 2011. Until people of color are better represented in cancer statistics and research, the answers to questions about how race affects disease development and outcomes will remain elusive.

It has been proved that socioeconomic factors — like education, income, and the environments that people live in — affect people’s health in many ways. The U.S. government has designed plans to address these health disparities and inequities. Many research agencies recommend measures to increase diversity in research studies and clinical trials and to focus research on bridging gaps in care.

Talk With Others Who Understand

MyMyelomaTeam is the social network for people with myeloma and their loved ones. On MyMyelomaTeam, more than 15,000 members come together to ask questions, give advice, and share their stories with others who understand life with myeloma.

Do you have questions about how race affects myeloma? Share your experience in the comments below, or start a conversation by posting on your Activities page.