TY - JOUR
T1 - Associations of reproductive breast cancer risk factors with breast tissue composition
AU - Yaghjyan, Lusine
AU - Austin-Datta, Rebecca J.
AU - Oh, Hannah
AU - Heng, Yujing J.
AU - Vellal, Adithya D.
AU - Sirinukunwattana, Korsuk
AU - Baker, Gabrielle M.
AU - Collins, Laura C.
AU - Murthy, Divya
AU - Rosner, Bernard
AU - Tamimi, Rulla M.
N1 - Funding Information:
This work was supported by the National Cancer Institute at the National Institutes of Health [CA240341 to L.Y., CA131332, CA175080, P01 CA087969 to R.M.T.; UM1 CA186107 to M.S.; U01 CA176726 to W.W.], Avon Foundation for Women, Susan G. Komen for the Cure®, Breast Cancer Research Foundation, and the BIDMC High School Summer Research Program to A.D.V.
Funding Information:
This work was supported by the National Cancer Institute at the National Institutes of Health [CA240341 to L.Y.; CA131332, CA175080, P01 CA087969 to R.M.T.; UM1 CA186107 to M.S.; U01 CA176726 to W.W.], Avon Foundation for Women, Susan G. Komen for the Cure®, Breast Cancer Research Foundation, and the BIDMC High School Summer Research Program to A.D.V.
Publisher Copyright:
© 2021, The Author(s).
PY - 2021/12
Y1 - 2021/12
N2 - Background: We investigated the associations of reproductive factors with the percentage of epithelium, stroma, and fat tissue in benign breast biopsy samples. Methods: This study included 983 cancer-free women with biopsy-confirmed benign breast disease (BBD) within the Nurses’ Health Study and Nurses’ Health Study II cohorts. The percentage of each tissue type (epithelium, stroma, and fat) was measured on whole-section images with a deep-learning technique. All tissue measures were log-transformed in all the analyses to improve normality. The data on reproductive variables and other breast cancer risk factors were obtained from biennial questionnaires. Generalized linear regression was used to examine the associations of reproductive factors with the percentage of tissue types, while adjusting for known breast cancer risk factors. Results: As compared to parous women, nulliparous women had a smaller percentage of epithelium (β = − 0.26, 95% confidence interval [CI] − 0.41, − 0.11) and fat (β = − 0.34, 95% CI − 0.54, − 0.13) and a greater percentage of stroma (β = 0.04, 95% CI 0.01, 0.08). Among parous women, the number of children was inversely associated with the percentage of stroma (β per child = − 0.01, 95% CI − 0.02, − 0.00). The duration of breastfeeding of ≥ 24 months was associated with a reduced proportion of fat (β = − 0.30, 95% CI − 0.54, − 0.06; p-trend = 0.04). In a separate analysis restricted to premenopausal women, older age at first birth was associated with a greater proportion of epithelium and a smaller proportion of stroma. Conclusions: Our findings suggest that being nulliparous as well as having a fewer number of children (both positively associated with breast cancer risk) is associated with a smaller proportion of epithelium and a greater proportion of stroma, potentially suggesting the importance of epithelial-stromal interactions. Future studies are warranted to confirm our findings and to elucidate the underlying biological mechanisms.
AB - Background: We investigated the associations of reproductive factors with the percentage of epithelium, stroma, and fat tissue in benign breast biopsy samples. Methods: This study included 983 cancer-free women with biopsy-confirmed benign breast disease (BBD) within the Nurses’ Health Study and Nurses’ Health Study II cohorts. The percentage of each tissue type (epithelium, stroma, and fat) was measured on whole-section images with a deep-learning technique. All tissue measures were log-transformed in all the analyses to improve normality. The data on reproductive variables and other breast cancer risk factors were obtained from biennial questionnaires. Generalized linear regression was used to examine the associations of reproductive factors with the percentage of tissue types, while adjusting for known breast cancer risk factors. Results: As compared to parous women, nulliparous women had a smaller percentage of epithelium (β = − 0.26, 95% confidence interval [CI] − 0.41, − 0.11) and fat (β = − 0.34, 95% CI − 0.54, − 0.13) and a greater percentage of stroma (β = 0.04, 95% CI 0.01, 0.08). Among parous women, the number of children was inversely associated with the percentage of stroma (β per child = − 0.01, 95% CI − 0.02, − 0.00). The duration of breastfeeding of ≥ 24 months was associated with a reduced proportion of fat (β = − 0.30, 95% CI − 0.54, − 0.06; p-trend = 0.04). In a separate analysis restricted to premenopausal women, older age at first birth was associated with a greater proportion of epithelium and a smaller proportion of stroma. Conclusions: Our findings suggest that being nulliparous as well as having a fewer number of children (both positively associated with breast cancer risk) is associated with a smaller proportion of epithelium and a greater proportion of stroma, potentially suggesting the importance of epithelial-stromal interactions. Future studies are warranted to confirm our findings and to elucidate the underlying biological mechanisms.
KW - Age at first child
KW - Benign breast disease
KW - Breast cancer risk
KW - Breastfeeding
KW - Parity
UR - http://www.scopus.com/inward/record.url?scp=85110836309&partnerID=8YFLogxK
U2 - 10.1186/s13058-021-01447-2
DO - 10.1186/s13058-021-01447-2
M3 - Article
C2 - 34225771
AN - SCOPUS:85110836309
SN - 1465-5411
VL - 23
JO - Breast Cancer Research
JF - Breast Cancer Research
IS - 1
M1 - 70
ER -
