Dietary Mushroom Intake and the Risk of Breast Cancer Based on Hormone Receptor Status

Abstract

Although many studies have documented the antitumor activities of mushrooms, the association between mushroom intake and breast cancer, defined by hormone receptor status, has received minimal empirical investigation. This study evaluated the association between mushroom intake and the risk of breast cancer according to hormone receptor status among Korean women. Mushroom intake and breast cancer risk were examined among 358 breast cancer patients and 360 cancer-free controls. Intake of mushrooms was assessed using a quantitative food frequency questionnaire. Greater mushroom intake was related to lower risk of breast cancers among premenopausal women (odds ratio [OR] = 0.35, 95% confidence interval [CI] = 0.13–0.91 for the highest vs. the lowest quartile intake). The association was stronger for premenopausal women with estrogen receptor (ER)+/progesterone receptor (PR) + tumors (OR = 0.30, 95% CI = 0.11–0.79 for the highest vs. the lowest quartile intake) than those with ER–/PR– tumors. Our results suggest that high consumption of mushrooms might be related to lower risks for breast cancers among premenopausal women; this association may be more robust among women with hormone receptor positive tumors.

ACKNOWLEDGMENT

This study was funded by the Korean Science and Engineering Foundation (R01-2007-000-11293-0).

Notes

^aAbbreviations are as follows: BMI, body mass index; METs, metabolic equivalent units.

^b n = 360.

^c n = 358.

^dMean ± SD.

^eMETs are multiples of the resting metabolic rate and calculated using the short form (version 2.0, April 2004) of the International Physical Activity Questionnaire.

^fIn postmenopausal women.

^aAbbreviations are as follows: OR, odds ratio; 95% CI, 95% confidence interval; Q, quartile.

^bTotal adjusted for age (continuous), body mass index (calculated as weight/kg divided by height m2; <18.5, 18.5–23, 23–25, and ≥25), family history of breast cancer (yes/no), current use of dietary supplements (yes/no), education (≤elementary school, middle school, high school, and ≥college), job (housewife, profession/office worker, sales/service, agriculture/laborer/unemployed, and others), smoking (nonsmoker, ex-smoker, current smoker), alcohol intake (never, ever), physical activity (metabolic units min/wk; ≤396, 396–1,272, 1,272 < 2,772, and ≥2,772), menopausal status (pre menopausal/postmenopausal), age at menarche (≤13, 14, 15, and ≥16 yr), parity (yes/no), total energy intake (continuous), and vegetable intake (continuous). Premenopausal: adjusted for the same covariates as the model among total subjects with the exception of menopausal status. Postmenopausal: additionally adjusted for postmenopausal hormone use (never, ever).

^cTest for trends calculated with the median intake for each category of mushroom intake as a continuous variable.

^†Test for trend calculated with the median intake for each category of mushroom intake as a continuous variable.

^‡Total: Adjusted for age (continuous), body mass index (calculated as weight in kilograms divided by the square of the height in meters; <18.5, 18.5–23, 23–25, and ≥25), family history of breast cancer (yes/no), current use of dietary supplements (yes/no), education (≤elementary school, middle school, high school, and ≥college), job (housewife, profession/office worker, sales/service, agriculture/laborer/unemployed and others), smoking (nonsmoker, ex-smoker, current smoker), alcohol intake (never, ever), physical activity (Met-min/week; ≤396, 396–1272, 1272–<2772, and ≥2772), menopausal status (pre/post), age at menarche (≤13, 14, 15, and ≥16), parity (yes/no), total energy intake (continuous), vegetable intake (continuous)