Abstract

Abstract 4967

Background:

Multiple myeloma (MM) is a common hematological malignancy affecting all races and the incidence is increasing. The rise in incidence is partly due to an increase in average life span in the patient population above the age of 65. It is estimated that 21, 700 individuals will be diagnosed with and 10, 710 patients will die of myeloma in 2012. The comparative epidemiological and survival data on different ethnic groups has not been analyzed on a large population scale. The aim of this study is to analyze and compare the epidemiologic and survival parameters of MM in major US ethnic groups which may provide new insights into disease pathophysiology.

Methods:

The SEER (Surveillance Epidemiology and End Results) database has been reporting cancer incidence since 1973. Using SEER 18 registries database 1973–2009, appropriate frequency and survival analyses (Kaplan-Meier survival method age adjusted) were performed and compared.

Results:

US whites (USW) accounted for the highest reported cases (77%) while the next highest reported cases were AA population (17%) (Table 1). On the contrary, the incidence of MM was highest in AA (11. 7%) and lowest in the US-Hispanic group (3. 4%). Male to female distribution was similar among groups. The median age at diagnosis was 63yrs in AA and 62yrs in US-Asians compared to ∼70yrs in the other ethnic groups. The cancer at presentation was more advanced in the AA and US-Asian groups. However, as shown in both Tables 1 & 2, the mortality rates were significantly lower in the US-Asian population when compared to other ethnic groups (2. 4%).

Table 1:

Comparison of selected variables of MM among major US ethnic groups

VariablesAllUSWAAHispanicUS-Asian
Reported cases (%) 79,186 (100%) 61,083 (77%) 13,611 (17%) 2,393 (3%) 1,872 (3%) 
Incidence rate 5.8 5.3 11.7* 3.4 4.1 
Male 7.4 6.9 14.3 6.3 4.7 
Female 4.7 4.1 10.1 4.7 3.9 
M% - F% 53%–47% 54%–46% 49%–51% 53%–47% 49%–51% 
Median age of diagnosis 69 71 63* 70 62* 
Age <50 at diagnosis 23% 21% 28%* 19%* 31%* 
Advance stages 83% 79% 89%* 81% 92%* 
Mortality rate 3.7 3.4 6.6* 2.8 2.4* 
Male 4.4 4.1 3.3 2.8 
Female 2.7 2.5 5.4 2.3 1.9 
VariablesAllUSWAAHispanicUS-Asian
Reported cases (%) 79,186 (100%) 61,083 (77%) 13,611 (17%) 2,393 (3%) 1,872 (3%) 
Incidence rate 5.8 5.3 11.7* 3.4 4.1 
Male 7.4 6.9 14.3 6.3 4.7 
Female 4.7 4.1 10.1 4.7 3.9 
M% - F% 53%–47% 54%–46% 49%–51% 53%–47% 49%–51% 
Median age of diagnosis 69 71 63* 70 62* 
Age <50 at diagnosis 23% 21% 28%* 19%* 31%* 
Advance stages 83% 79% 89%* 81% 92%* 
Mortality rate 3.7 3.4 6.6* 2.8 2.4* 
Male 4.4 4.1 3.3 2.8 
Female 2.7 2.5 5.4 2.3 1.9 
*

P<0. 01 compared to all reported cases of MM.

Table 2:

Comparison of survival among major US ethnic groups with MM

SurvivalAllUSWAAHispanicUS-Asian
1 – year 71% 70% 72% 71% 76%* 
2 – year 56% 55% 57% 54% 59%* 
3 – year 45% 44% 46% 45% 51%* 
4 – year 36% 35% 37% 34% 42%* 
5 – year 29% 28% 30% 28% 34%* 
SurvivalAllUSWAAHispanicUS-Asian
1 – year 71% 70% 72% 71% 76%* 
2 – year 56% 55% 57% 54% 59%* 
3 – year 45% 44% 46% 45% 51%* 
4 – year 36% 35% 37% 34% 42%* 
5 – year 29% 28% 30% 28% 34%* 
*

P<0. 01 compared to all reported cases of MM.

Conclusions:

Our analysis shows that the incidence of MM is highest in AA population, with more males affected than females, and least common in US-Asian population, more specifically US-Asian women. Interestingly, we observed that not only the average age of diagnosis is significantly less in both groups, but those presenting with an advanced stage are also significantly increased in number. However, the improved mortality rates and survival in US-Asians may be attributed to differences in tumor biology, cytogenetics, emigrational factors, higher socioeconomic status, better health care, higher educational background with awareness, lifestyle and environmental factors such as dietary habits and obesity. Large scale epidemiological studies performed by Alexander et al in 2007 demonstrated an association between obesity and an increased risk of MM whereas dietary factors such as increased consumption of green vegetables and fish was linked to a decrease in risk. Molecular and cytogenetic studies are warranted to examine the behavior and biology of MM in these AA and US-Asian ethnicities, directly comparing the treatment and management of this particular disease, which may translate into better understanding of pathogenesis and identification of prognostic factors leading to improvements in treatment.

Disclosures:

No relevant conflicts of interest to declare.

Author notes

*

Asterisk with author names denotes non-ASH members.