An area's level of poverty or wealth may affect the distribution of cancer types

A new analysis has found that certain cancers are more concentrated in areas with high poverty, while other cancers arise more often in wealthy regions. Also, areas with higher poverty had lower cancer incidence and higher mortality than areas with lower poverty. Published early online in CANCER, a peer-reviewed journal of the American Cancer Society, the study's findings demonstrate the importance of including measures of socioeconomic status in national cancer surveillance efforts.

Overall, socioeconomic status is not related to cancer risk - cancer strikes the rich and poor alike. However, socioeconomic status does seem to influence the type of cancer a person may develop. To look closely at the issue, Francis Boscoe, PhD, of the New York State Cancer Registry and his colleagues compared people living in areas with the highest poverty with those living in areas with the lowest poverty. The investigators assigned nearly three million tumors diagnosed between 2005 and 2009 from 16 states plus Los Angeles (an area covering 42 percent of the US population) into one of four groupings based on the poverty rate of the residential census tract at time of diagnosis.

For all cancer types combined, there was a negligible association between cancer incidence and poverty; however, 32 of 39 cancer types showed a significant association with poverty (14 positively associated and 18 negatively associated). Certain cancers - Kaposi sarcoma and cancers of the larynx, cervix, penis, and liver - were more likely in the poorest neighborhoods, while other cancers - melanoma, thyroid, other non-epithelial skin, and testis - were more likely in the wealthiest neighborhoods.

"At first glance, the effects seem to cancel one another out. But the cancers more associated with poverty have lower incidence and higher mortality, and those associated with wealth have higher incidence and lower mortality," explained Dr. Boscoe. "When it comes to cancer, the poor are more likely to die of the disease while the affluent are more likely to die with the disease."

Cancer Disparities by Race/Ethnicity and Socioeconomic Status This article highlights disparities in cancer incidence, mortality, and survival in relation to race/ethnicity, and census data on poverty in the county or census tract of residence. The incidence and survival data derive from the National Cancer Institute's (NCI) Surveillance, Epidemiology, and End Results (SEER) Program; mortality data are from the National Center for Health Statistics (NCHS); data on the prevalence of major cancer risk factors and cancer screening are from the National Health Interview Survey (NHIS) conducted by NCHS.

For all cancer sites combined, residents of poorer counties (those with greater than or equal to 20% of the population below the poverty line) have 13% higher death rates from cancer in men and 3% higher rates in women compared with more affluent counties (less than 10% below the poverty line). Differences in cancer survival account for part of this disparity. Among both men and women, five-year survival for all cancers combined is 10 percentage points lower among persons who live in poorer than in more affluent census tracts. Even when census tract poverty rate is accounted for, however, African American, American Indian/Alaskan Native, and Asian/Pacific Islander men and African American and American Indian/Alaskan Native women have lower five-year survival than non-Hispanic Whites. More detailed analyses of selected cancers show large variations in cancer survival by race and ethnicity. Opportunities to reduce cancer disparities exist in prevention (reductions in tobacco use, physical inactivity, and obesity), early detection (mammography, colorectal screening, Pap tests), treatment, and palliative care.