Li X, Wu W, Giovannucci E, et al. - In view of the links between elevated cutaneous nevus number and longer telomeres and the recent large systematic Mendelian randomization study demonstrating a significant positive association between telomere length and risk of cancer, researchers examined if a correlation exists between a higher nevus count, a phenotypic marker of longer telomere, and increased risk of internal cancer. Further, they prospectively investigated participants in the Nurses’ Health Study (NHS, 1986–2012) and the Nurses’ Health Study 2 (NHS2, 1989–2013) for the association between nevus count and total as well as site-specific cancer risk using Cox proportional hazards models. A total of 23,004 internal cancer cases (15,484 in the NHS and 7,520 in the NHS2) were recorded during 3,900,264 person-years of follow-up. Compared with participants who had no nevi, women with 1–5 nevi had the multivariate HRs of total cancer (excluding skin cancer) of 1.06 (95% confidence interval [CI], 1.03–1.09), those who had 6–14 nevi had the HRs of total cancer (excluding skin cancer) of 1.08 (95% CI, 1.03–1.15), and those with 15 or more nevi had HRs of total cancer (excluding skin cancer) of 1.19 (95% CI, 1.05–1.35). Findings here support that the number of cutaneous nevi as a phenotypic marker is connected with internal cancer risk, which may be explained by telomere biology.