Selected Articles from This Issue

DOI: Published October 2020

County-Level Persistent Poverty and Cancer Mortality Rates

Moss et al. Page 1949

Moss and colleagues assessed disparities in cancer mortality by county-level persistent poverty, that is, whether counties continuously experienced high levels of poverty since 1980. The authors merged 2007 to 2011 data from the National Center for Health Statistics (cancer mortality rates) and American Community Survey (poverty classifications). Overall cancer mortality rates were 12.3% higher in persistent poverty counties versus all others, and 9.6% higher in persistent versus current poverty counties, with even greater disparities observed for specific cancer sites. Persistent poverty counties have exceptionally high cancer mortality, and targeted research, policy, and intervention efforts are needed to reduce these geographic disparities in cancer.

Higher Plasma Amyloid-Beta Levels Are Associated with a Higher Risk of Cancer

van der Willik et al. Page 1993

Many studies have shown that patients with Alzheimer disease are at decreased risk of cancer, but this inverse relation is likely to be biased by surveillance and survival bias. To overcome such bias, van der Willik and colleagues determined the relation between plasma amyloid-β levels—a preclinical feature of Alzheimer disease—and the risk of cancer in a population-based setting. They showed that higher levels of plasma amyloid-β were associated with a higher risk of cancer, suggesting a potential biological link between Alzheimer disease and cancer. The pathophysiologic role of amyloid-β in cancer and its causality warrant further investigation.

SEMs Are Associated with Risk of Breast Cancer, Lung Cancer, and Mature B-cell Neoplasms

Gagliardi et al. Page 2026

The total number of stochastic epigenetic mutations (SEM) has been proposed as a biomarker of accumulation of exposure-related DNA damage, but its predictive role in cancer has scarcely been studied. In three prospective cohorts including eight types of cancer, the total number of SEMs was associated with increased risk of breast, lung, and mature B-cell cancers in pre-diagnostic blood samples. Extreme outliers of methylation levels seem to occur more often in functional genomic regions regulated by components of the PRC2 complex. Identified SEMs suggest a possible carcinogenesis mechanism and may represent a potential biomarker for cancer early detection.

Associations between Serum Calcium, 25-Hydroxy Vitamin D, and the Risk of Primary Liver Cancer

Yin et al. Page 2057

The study conducted by Yin and colleagues was a case–control study nested in the Linxian Nutrition Intervention Trial cohorts with over 22-years of follow-up, which evaluated the independent and joint associations between serum calcium, 25-hydroxy vitamin D, and the risk of primary liver cancer prospectively at the first time. Low and high serum calcium resulted in increased risk, whereas high serum 25(OH)D was a protective factor. In a nutrient-deficient population, serum calcium and 25(OH)D could potentially be modifiable risk or protective factors, providing potential targets for primary liver cancer prevention and control.