Abstrak: High mammographic density is a strong breast cancer risk factor. Density normally declines with aging. We investigated whether the level of decline in mammographic density is related to breast cancer risk using a nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC)-Prospect cohort. This cohort was recruited among participants of a population-based breast cancer screening program in the Netherlands between 1993 and 1997. We examined whether age-related changes in mammographic density were different for 533 cases and 1,367 controls who were 49-69 years of age at the time of recruitment into the cohort. We used mixed models with linear and quadratic terms for age and interaction terms between age terms and case status. The percent mammographic density at the first available mammogram was higher for cases than for controls (25.2% vs. 22.5%) (P = 0.003). The average decline in density over 10 years was 11% in both cases and controls (P = 0.56). When studying changes among 4 categories of density, we saw some indication that large changes may influence breast cancer risk. Although no difference was seen in the average decline, we cannot exclude that large changes may influence breast cancer risk.

Abstrak: Persistent cervical infections by approximately 15 carcinogenic genotypes of human papillomavirus (HPV) cause virtually all cases of cervical cancer and its immediate precancerous precursor, cervical intraepithelial neoplasia grade 3 or carcinoma in situ. As is shown in a meta-analysis by Koshiol et al. (Am J Epidemiol 2008;168:123–137), detection of carcinogenic HPV viral persistence could be used to identify women at the greatest risk of cervical precancer. Specifically, women who have carcinogenic HPV infection that persists for at least 1 year versus those whose infections clear are at significantly elevated risk of having or developing cervical precancer. However, before detection of HPV persistence can be used in cervical cancer screening, several considerations need to be addressed: 1) validation and Food and Drug Administration approval of a reliable HPV genotyping test, 2) rational clinical algorithms based on risk of precancer and cancer for the clinical management of HPV persistence, 3) clinician and patient acceptability of monitoring of HPV infections (including not responding excessively to the first positive HPV test and waiting 1–2 years for infections to either persist or resolve), and 4) patient compliance with recommended follow-up. Investigators will need to address these and other key issues in order to realize the potential utility of HPV viral monitoring for improving the accuracy of cervical cancer screening.