Open AccessAssociation between vitamin D and calcium intake and breast cancer risk according to menopausal status and receptor status in Japan
Author(s) -
Kawase Takakazu,
Matsuo Keitaro,
Suzuki Takeshi,
Hirose Kaoru,
Hosono Satoyo,
Watanabe Miki,
Inagaki Masaki,
Iwata Hiroji,
Tanaka Hideo,
Tajima Kazuo
Publication year - 2010
Publication title -
cancer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 1347-9032
DOI - 10.1111/j.1349-7006.2010.01496.x
Subject(s) - breast cancer , medicine , vitamin d and neurology , calcium , calcitriol receptor , physiology , endocrinology , oncology , cancer
Although several studies have investigated the possible association between elevated vitamin D and calcium intake and low breast cancer risk, findings have been inconsistent. We conducted a case‐control study to clarify the association between vitamin D and calcium intake and breast cancer risk among pre‐ and post‐ menopausal women in Japan. We also investigated whether these effects were modified by tumor receptor status, specifically estrogen receptor (ER), progesterone receptor (PR), or human epidermal growth factor receptor‐2 (HER2) status. We examined 1803 breast cancer patients and 3606 age‐ and menopausal status‐matched noncancer controls. Among cases, 713 were assessed for ER, PR, and HER2 status. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using conditional or unconditional logistic models adjusted for potential confounders. A significant inverse association was observed between vitamin D and calcium intake and breast cancer risk among all subjects, with top quartile ORs of 0.76 (95% CI, 0.63–0.90; trend P = 0.001) and 0.83 (95% CI, 0.69–0.99; trend P = 0.038), respectively. In analyses stratified by menopausal status, a significant association between risk and vitamin D was observed only among premenopausal women (trend P < 0.001), whereas that between risk and calcium intake was seen only among postmenopausal women (trend P = 0.022). Heterogeneity by menopausal status for these associations was statistically significant. This association was modified by tumor receptor status. These findings suggest that the protective effects of vitamin D and calcium intake against breast cancer risk may differ by menopausal status and receptor status. ( Cancer Sci 2010; 101: 1234–1240)