Overall, patients diagnosed with multiple myeloma have better prognoses than ever before, thanks to novel treatment strategies that have emerged over the past decade.
Ethnicity and race, however, predict different outcomes and treatment patterns, according to analyses of information from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database by medical oncologist Sikander Ailawadhi, MD, of the Mayo Clinic in Jacksonville, Florida, and colleagues.1-3
“We know there’s differential drug utilization by ethnicity — but not exactly why,” Dr Ailawadhi said.
There are, for example, differences in the incidence of myeloma defining events (MDEs), his team found.
Until 2005, MDE rates had steadily increased overall, the researchers reported. But then between 2006 and 2010, MDE rates abruptly began to decline.
“We are not waiting very long for the disease to cause damage to the body,” Dr Ailawadhi explained. “In 2015, the definition of active myeloma was modified to include patients who in the past were considered to have ‘smoldering myeloma.’ Those patients are now treated for active disease because of the very high risk of progression.”
That may be a reason MDE rates for the Medicare patient population declined between 2006 and 2010.
But overall trends in MDE rates can obscure important differences among patients of different ethnicities. African-Americans had the highest rates of all MDEs — except for bone fractures, Dr Ailawadhi said, perhaps because African-Americans tend to have denser bone tissue.
Other symptoms of MDEs were more frequent in African-Americans, which “might be a sign” that they are receiving treatment later in the disease process, Dr Ailawadhi said.
It is probably not, however, the case that multiple myeloma is more aggressive among African-American patients.
“We don’t have good comprehensive analyses comparing disease biology between African-American, white, Hispanic, and Asian patients,” he said. “We do know that multiple myeloma is more frequent and happens at younger ages among African-Americans.”
But African-Americans actually have better survival rates than other myeloma patient populations, Dr Ailawadhi and his colleagues found. If anything, he said, African-Americans might have “a slightly lower risk” of myeloma cells harboring aggressive mutations.