Predictive and Prognostic Factors Associated with the Incidence and Mortality of Hematologic Malignancies

Background:

Identifying individual and systemic risk factors are key to reducing cancer incidence and improving mortality. Unfortunately for hematologic malignancies, few clear-cut common cause-and-effect relationships exist. Multiple myeloma has been associated with Black race and obesity, and the lymphomas and leukemias differ in incidence with age. In order to identify potential risk factors, in this study we compared incidence and mortality rates among U.S. states for myeloma, all leukemias and lymphomas, and correlated these rates with the prevalence of several lifestyle and demographic characteristics.

Methods:

Data came from the following sources: cancer incidence and mortality data from 1999-2015 came from the CDC WONDER database; race and poverty prevalence from the 2015 American Community Survey; gross domestic product (GDP) data from the Bureau of Economic Analysis; median household income from the Census Bureau; and weight and physical activity data from the Behavioral Risk Factor Surveillance System survey. Spearman's rank correlation coefficient was used to compare cancer incidence/mortality and potential risk factors.

Results:

Myeloma incidence and mortality were more common in obese individuals (incidence, rho = 0.27, P = 0.05; mortality, 0.38, P = 0.006) and individuals identifying as Black (0.65, P < 0.001; 0.42, P = 0.002). Incidence was lower in physically active individuals. (-0.51, P < 0.001).

Leukemia incidence and mortality were more common in individuals identifying as white (0.45, P = 0.001; 0.36, P = 0.009). Mortality was positively associated with obesity (0.39, P = 0.005), and negatively associated with physical activity (-0.36, P = 0.009) and median household income (-0.39, P = 0.004).

Lymphoma incidence and mortality were more common in white individuals (0.38, P = 0.006; 0.40, P = 0.004). Incidence was negatively associated with state poverty percentage (-0.40, P = 0.003). Mortality was positively associated with obesity (0.35, P = 0.01), and negatively associated with a healthy weight (-0.35, P = 0.01).

Discussion:

This data suggests that weight and activity are modifiable risk factors for a variety of hematologic cancers, while race may be a non-modifiable risk factor. Individual and state wealth do not appear to play a large role in incidence or mortality. Although further study is needed, these results underscore the importance of maintaining a healthy weight and regular physical activity in cancer prevention. This data also confirms the higher incidence of myeloma in Black individuals and suggests lymphoma and leukemias may be more common among those identifying as white.