Racial disparities in incidence and outcome in multiple myeloma: a population-based study

Abstract

Multiple myeloma (MM) is the most common hematologic malignancy in blacks. Some prior studies suggest inferior survival in blacks; others suggest similar survival. Using the original 9 Surveillance, Epidemiology, and End Results registries, we conducted a large-scale population-based study including 5798 black and 28 939 white MM patients diagnosed 1973-2005, followed through 2006. Age-adjusted incidence rates, diseasespecific survival, and relative survival rates were calculated by race, age, and time period of diagnosis. Mean age at diagnosis was 65.8 and 69.8 years for blacks and whites, respectively (P < .001). Incidence among blacks was m twice that among whites; this disparity was greater among patients < 50 years (P ‫؍‬ .002). Over the entire study period, diseasespecific and relative survival rates were higher in blacks than whites (P < .001). IntroductionMultiple myeloma (MM) is the most common hematologic malignancy among blacks in the US and the second most common hematologic malignancy in the country. 1,2 M 20 000 new cases are diagnosed annually. 1,2 MM is characterized by clonal expansion of plasma cells. Classic clinical manifestations include hypercalcemia, renal failure, anemia, and lytic bone lesions as well as recurrent bacterial infections and extramedullary soft-tissue plasmacytomas. 3,4 Recent data show that MM is consistently preceded by monoclonal gammopathy of undetermined significance (MGUS). 5,6 Compared with whites, MGUS has been noted to occur twice as frequently in blacks, with similar transformation rates in blacks and whites. [7][8][9][10] Although the etiology of MM remains unclear, observed racial disparity patterns and reported familial clustering in MGUS and MM suggest a role for susceptibility genes. 11,12 There have been few published descriptive studies of MM incidence and survival by race. Prior data from the Statistics, Epidemiology, and End Results (SEER) program and the Multiple Risk Factor Intervention Trial have shown consistently higher incidence and mortality among blacks. 13,14 However, mortality reflects the combined impact of cancer incidence and outcome, whereas survival is a measure of cancer outcome separate from incidence. A prior single-center study found poorer survival among 52 patients with MM at a predominantly black hospital compared with 92 patients at a predominantly white hospital; however, this difference did not persist when adjusted for socioeconomic status. 15 Similarly, a single-institution review of records for 292 patients with MM found that neither race nor socioeconomic status independently related to overall survival. 16 Retrospective data from the Southwest Oncology Group showed comparable outcomes among blacks and whites before the advent of autologous stem cell transplantation (ASCT). 17 A recent study of 91 patients receiving ASCT in an equal access health system observed no difference in survival by race 18 a registry study by the Center for International Bone Marrow Transplantation confirmed this finding. 19 Four population-based stu...

ESRD due to Multiple Myeloma in the United States, 2001–2010

“…These results mirror recent findings from a Surveillance, Epidemiology, and End Results Program study, in which survival rates in black patients with multiple myeloma were significantly higher than in white patients. 24 This survival benefit is likely not entirely explained by improved dialysis survival among black versus white patients, suggesting disease heterogeneity by race, as African Americans are less likely to undergo autologous stem cell transplant or to receive chemotherapy than other races. [25][26][27] As secular trends in survival demonstrate a more pronounced improvement in white than in black patients with multiple myeloma, genetic factors, variable treatment response, or perhaps an indolent disease subtype may be among possible reasons that differences exist.…”

Impact of health care insurance on overall survival of patients with multiple myeloma and monoclonal gammopathy of undetermined significance

“…Most recently, analysis of the SEER data demonstrated superior survivals in African Americans but with improving survival in Caucasians, but not African Americans, with time over the study period of 1973 to 2005. [6,7] The last observation suggested differential access to newer therapies. However, we noted that survival was similar for all stages of disease and in a preliminary review of treatments that there were no differences in use of newer modalities.…”

“…[3][4][5][6] MM and MGUS are twice as common in African-Americans as in Caucasians and more common in males than females. [7][8][9][10] The prevalence of MGUS is 3% in people older than 50 years and patients with MGUS have an annual 1% risk of progression to MM or related malignant disorder. [11][12][13][14] Advances in therapeutic options such as proteasome inhibitors, immune modulatory drugs (IMDs) and stem cell transplantation (SCT) have improved the prognosis and survival of patients with MM.…”

Monoclonal Gammopathy of Undetermined Significance and Multiple Myeloma in Older Adults

“…MGUS and MM are more common in men than in women, and in African Americans than in white people. 1,2,4,5 Five-year overall survival in MM has increased from 29.7% in 1990 to 45.1% in 2007, 2 largely attributable to novel therapies. 6 Given the anticipated growth in the older adult population and presumably static prevalence rates as a function of age, the raw numbers of older adults with plasma cell disorders will increase over time.…”