Key takeaways
- Multiple myeloma occurs twice as often in Black Americans as in white Americans.
- Genetic differences, environmental factors, and disparities in healthcare access all contribute to the increased rate of diagnosis in Black people.
- When access to care is equal, the outlook for multiple myeloma is slightly better among Black people than among white people.
Multiple myeloma (MM) is a type of cancer that affects bone marrow plasma cells.
Plasma cells are part of adaptive immunity. This means they make antibodies in response to harmful invaders like bacteria and viruses. When MM attacks plasma cells, however, it interferes with antibody production and reduces the body’s ability to fight infection.
Because MM suppresses the immune system, people with this cancer are more likely to experience recurring infections.
MM is rare in young people. According to the
Males develop MM slightly more often than females. Other factors can also increase the chance of diagnosis. These include:
- family history
- obesity and overweight
- history of other plasma cell diseases
While MM can affect people of all races, Black Americans are
This disparity raises questions about possible causes and how to bridge the gap to improve outcomes.
MM begins with a blood abnormality called monoclonal gammopathy of undetermined significance (MGUS). It has no symptoms and is characterized by an atypical protein found in blood without any other MM criteria.
MGUS can remain premalignant (may become cancerous but isn’t at the moment), or it can progress to become smoldering multiple myeloma (SMM) and finally MM.
MGUS and SMM always happen before MM, though many people who have MGUS or SMM never develop cancer. Only a small percentage of people develop malignant (cancerous) MM.
MGUS occurs in the general population, and rates of diagnosis increase with age. However, it’s found more often and diagnosed at earlier ages in Black Americans. This means they have an increased risk of developing MM.
A 2014 study of 13,000 people found
In the study, MGUS was found in:
- 3.7% of Black people
- 2.3% of white people
- 1.8% of Hispanic people
Asian Americans have lower rates of occurrence than non-Hispanic white people.
While more research is needed to understand why there are racial and ethnic disparities in MGUS and MM risk, some factors that may include:
- family history and genetics
- obesity
- socioeconomic factors
While there may be some genetic differences at work, it’s unclear how much — if at all — they influence the higher rates of MM diagnoses in people of color.
Other possible factors may lead to MM, like obesity and type 2 diabetes (T2D), and both have a higher prevalence in the Black American population. This may partially account for the increased MM diagnoses seen in this group.
Studies on socioeconomic factors and their relationship to racial differences in MM have had mixed results. More research is needed to determine if and how they contribute to the observed increase in MM risk for Black people.
It’s unclear whether Black people are more likely to have genetic variations that influence their chances of developing MM or the severity of the disease.
Research from 2021 shows they are more likely to have immunoglobulin heavy chain gene translocations on chromosome 14. This suggests a higher risk of the condition.
They are also less likely to have a deletion of the gene TP53/17p, an indicator of pathology and shortened survival. This is a positive finding, meaning they’re less likely to have the cancer and more likely to survive it if they do.
Black people are also less likely than white people to have monosomy 13 and monosomy 17, per a
Overall, Black people may have a more favorable prognosis after MM diagnosis, according to data from the
More research in this area is needed to help address these disparities and enable equal access to care and treatment for all people who can benefit from it.
The increased prevalence of MGUS in Black Americans leads to a significantly higher rate of MM diagnosis. As of 2018, myeloma diagnosis
- Black (including Hispanic): 14.6 per 100,000 people
- American Indian and Alaska Native (including Hispanic): 7.6 per 100,000 people
- Hispanic (any race): 7.3 per 100,000 people
- White (including Hispanic): 6.7 per 100,000 people
- Non-Hispanic white: 6.6 per 100,000 people
- Asian and Pacific Islander (including Hispanic): 3.8 per 100,000 people
According to the
Healthcare professionals usually find MGUS unintentionally during blood tests done for other conditions, like anemia, bone problems, or kidney disorders.
If a doctor suspects MM, they can order additional tests such as urine, bone marrow, and imaging.
Community awareness can lead to better outcomes in healthcare because patients know when and how to self-advocate. Doctors also know to run additional tests when presented with common symptoms.
MM is a relatively rare cancer and isn’t well known in Black communities. Even primary care physicians can incorrectly assume that natural aging is the culprit behind many of the usual MM symptoms, such as:
- back pain
- frequent urination
- fatigue
- weakness
- constipation
Doctors need to be aware of racial differences in prevalence or family history of MM to avoid missing diagnoses and treatment opportunities.
Screening for MM can enable early detection and result in prompt intervention.
Cancers like prostate, breast, and colon are part of routine screening, and a simple blood test is all that’s required to identify plasma cell abnormalities associated with MM.
Targeted screening in higher-risk populations like Black Americans can speed up their treatment process.
Access to healthcare services is an important factor for condition diagnosis and treatment. A smaller percentage of Black Americans than white Americans have access to private insurance, according to the
People who are under age 65 with private insurance include 51% of Black Americans and 67% of white Americans.
People who are over age 65 years with private insurance include 28% of Black Americans and 44% of white Americans.
Less insurance coverage can mean fewer diagnostic steps and reduced treatment options.
Clinical trials bring new life saving treatments to people who need them, and they often give early access to those treatments for trial participants.
However, a trial is only beneficial to the type of patient it represents. Too often, minority populations are underrepresented in trials, so the outcomes may not fully target the needs of their communities.
Black Americans are one such community. A series of lung cancer trials described by The American Society of Clinical Oncology had an African American participation rate of only 4%, and Black participants were similarly underrepresented in other cancer trials.
MM may not be curable, but it is treatable. The goal of treatment is to control cancer progression and improve quality of life.
Treatment usually starts after the stages of MGUS and SMM, when those affected have developed symptomatic MM.
Treatments for MM include:
- high dose therapy
- autologous stem cell transplantation
- immunomodulatory drugs
- proteasome inhibitors
- monoclonal antibodies
- histone deacetylase inhibitor
- nuclear transport inhibitor
- antibody drug conjugate
Public health experts agree that when MM outcomes are poorer for African Americans, it’s the result of socioeconomic factors that restrict access to timely and quality medical care.
In fact, multiple myeloma has a better outlook in Black people than in white people when they have equal access to care.
Whether early interventions can help people with MM depends on the stage or type of abnormality present.
Healthcare professionals will treat solitary plasmacytomas, or single plasma cell tumors, with radiation or surgery.
SMM is asymptomatic and treatment isn’t required. Instead, people with SMM are monitored in case they develop MM, at which point they’ll begin treatments.
Although the rate of diagnoses in Black Americans is double the rate in white Americans, the 5-year outlook appears to be much closer, based on the
- Black Americans: 53.3% of people with the disease survived 5 years
- White Americans: 52.5% of people with the disease survived 5 years
Research in multiple myeloma suggests that Black patients are less likely than white patients to have certain high-risk cytogenetic abnormalities, including:
- t(4;14)
- del17p / TP53
Both are linked with higher-risk disease and worse prognosis, so a lower frequency could help explain why some studies show better outcomes when access to treatment is equal.
MM is a blood plasma cancer usually found in older adults. It’s diagnosed approximately twice as often in Black Americans as in white Americans.
Higher instances of the MM precursor MGUS occur in Black populations, as well as other MM predictive factors like family history, T2D, and being overweight. However, it’s unclear whether genetic differences play a role in increased diagnoses.
Insufficient community awareness about MM, as well as reduced access to healthcare, likely play a role in the higher number of diagnoses in Black people. These communities are also underrepresented in clinical trials.
Increasing community awareness, access to adequate healthcare, and participation in clinical trials are all ways in which the Black population can close the diagnosis gap, reduce MM incidence, and improve treatment outcomes.