Highlights of This Issue

Data are conflicted about the efficacy of colonoscopy for reducing colon cancer risk. To address this question, Siegel and colleagues analyzed U.S. cancer surveillance data to gauge trends in population-based colorectal cancer incidence by tumor location. Data from cancer registries in the Surveillance, Epidemiology, and End Results (SEER) program were analyzed to quantify changes in rates by tumor location and disease stage. The authors report that, since 1999, incidence rates for both right- and left-sided colon tumors decreased annually in men and women. The authors suggest that increased colonoscopy utilization during the past decade may have contributed to a reduction in colon cancer incidence in the United States.

Folate is essential for one-carbon metabolism, and low dietary and circulating folate levels are both associated with increased risks of colorectal adenoma and cancer. Han and colleagues genotyped single-nucleotide polymorphisms in 82 one-carbon metabolism genes in colorectal cancer cases from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). The authors report that, whereas folate intake was inversely associated with advanced colorectal adenoma risk, no statistically significant associations were evident between one-carbon metabolism genes and adenoma risk. However, a statistically significant association was observed in the lowest quartile of folate intake. These results indicate that stratification by dietary folate intake can reveal associations between one-carbon metabolism genes and the risk of advanced colorectal adenoma.

It is not known if dairy intake after a prostate cancer diagnosis is associated with poor prognosis. To address this question, Pettersson and colleagues investigated post-diagnostic milk and dairy intake in relation to risk of lethal prostate cancer among participants in the Health Professionals Follow-Up Study. The authors found that total milk and dairy intake after diagnosis was not associated with a greater risk of lethal prostate cancer. The results of this study suggest that dairy intake after prostate cancer diagnosis is not associated with a greater risk of distant metastases and prostate cancer death.

Lindström and colleagues used prostate cancer cases within the National Cancer Institute Breast and Prostate Cancer Cohort Consortium (BPC3) to evaluate the performance of 25 independent single-nucleotide polymorphisms in prostate cancer risk models. The models combined genetic information with prostate cancer family history and age. The authors report that the best risk models included individual genetic markers along with family history of prostate cancer. These results indicate that incorporating genetic information and family history can be useful for identifying men that might benefit from prostate-specific antigen screening.