Polybrominated diphenyl ethers (
PBDEs) are suspected to be associated with
breast cancer risk because of their estrogenic potencies. Epidemiological studies of
PBDEs and
breast cancer are scarce. Our study aimed to estimate the association between adipose-tissue
PBDE concentrations and
breast cancer risk. A total of 209
breast cancer cases and 165 controls were recruited from hospitals between January 2014 and May 2016 in Shantou, Chaoshan area, China. Concentrations of 14
PBDE congeners were measured in adipose tissues obtained from the breast for cases and the abdomen/breast for controls during surgery. Demographic and clinicopathologic characteristics were obtained from medical records.
Breast cancer risk as well as clinicopathologic characteristics were evaluated by adipose-tissue
PBDE level. Odds ratios (
ORs) and 95% confidence intervals (95% CIs) for
breast cancer risk associated with levels of
PBDE congeners were estimated from logistic regression models for all cases and stratified by
estrogen receptor (ER) status. Level of total
PBDEs (∑PBDE) and most individual
PBDE congeners were higher in
breast cancer cases than controls (median ∑PBDE, 94.99 vs 73.72 ng/g
lipid). In the adjusted univariate model for all cases,
breast cancer risk was increased with both 2nd and 3rd tertiles versus the 1st tertile of
BDE-47 level (OR 2.05 [95% CI 1.08-3.92]; 5.47 [2.96-10.11]) and
BDE-209 level (2.48 [1.30-4.73]; 4.72 [2.52-8.83]) with trend (both P < 0.001) and with the 3rd tertile of
BDE-28 level (2.83 [1.63-4.92]),
BDE-99 (3.22 [1.85-5.60]),
BDE-100 (5.45 [2.90-10.23]), BDE-138 (2.40 [1.37-4.20]),
BDE-153 (1.74 [1.02-2.97]),
BDE-154 (1.84 [1.05-3.22]), and ∑PBDE levels (1.83 [1.07-3.14]) but decreased with the 3rd tertile of BDE-71 level (0.38 [0.22-0.65]) with trend (all P < 0.01). After stratifying by ER-positive or -negative status, the adjusted results were similar for ER-positive patients except for
BDE-153 and
BDE-154, with no statistical significance. In the multivariate model for all cases, age, menarche age,
BDE-47, 71, 99, 100, 183 and 209 were independent factors associated with
breast-cancer risk. ∑PBDE and most individual
PBDE congeners investigated were positively associated with
breast cancer risk in women from the Chaoshan area, China.
PBDE may play a role in the occurrence and development of
breast cancer.