Toenail-Based Metal Concentrations and Young-Onset Breast Cancer.

Toenail-Based Metal Concentrations and Young-Onset Breast Cancer. Am J Epidemiol. 2019 Jan 04;: Authors: O'Brien KM, White AJ, Jackson BP, Karagas MR, Sandler DP, Weinberg CR Abstract Several metals have carcinogenic properties, but their associations with breast cancer are not established. We studied cadmium, a "metalloestrogen", and nine other metals in relation to young-onset breast cancer (diagnosis age <50), which tends to be more aggressive than and have a different risk profile from later-onset disease. We measured recent metal exposure by assessing element concentrations in toenails from 1,217 disease-discordant sister pairs from the US-based Sister (2003-2009) and Two Sister (2008-2010) Studies. The metals - arsenic, cadmium, cobalt, chromium, copper, mercury, molybdenum, lead, tin, and vanadium - were assessed using inductively-coupled plasma mass spectrometry. We used conditional logistic regression to calculate odds ratios (OR) and 95% confidence intervals (CI). After correcting for differential calendar time of sample collection, we observed no statistically-significant associations between any metals and breast cancer. Vanadium had the largest OR (4th versus 1st quartile = 1.36, CI: 0.84, 2.21; P-for-trend = 0.17). Cadmium was associated with a small increase in risk, with no evidence of a dose-response relationship (4th versus 1st quartile OR = 1.15, CI: 0.82, 1.60; P-for-trend = 0.67). Previous case-control...
Source: Am J Epidemiol - Category: Epidemiology Authors: Tags: Am J Epidemiol Source Type: research