TY - JOUR
T1 - Expanding Our Understanding of Ovarian Cancer Risk
T2 - The Role of Incomplete Pregnancies
AU - Lee, Alice W.
AU - Rosenzweig, Stacey
AU - Wiensch, Ashley
AU - Ramus, Susan J.
AU - Menon, Usha
AU - Gentry-Maharaj, Aleksandra
AU - Ziogas, Argyrios
AU - Anton-Culver, Hoda
AU - Whittemore, Alice S.
AU - Sieh, Weiva
AU - Rothstein, Joseph H.
AU - Mcguire, Valerie
AU - Wentzensen, Nicolas
AU - Bandera, Elisa V.
AU - Qin, Bo
AU - Terry, Kathryn L.
AU - Cramer, Daniel W.
AU - Titus, Linda
AU - Schildkraut, Joellen M.
AU - Berchuck, Andrew
AU - Goode, Ellen L.
AU - Kjaer, Susanne K.
AU - Jensen, Allan
AU - Jordan, Susan J.
AU - Ness, Roberta B.
AU - Modugno, Francesmary
AU - Moysich, Kirsten
AU - Thompson, Pamela J.
AU - Goodman, Marc T.
AU - Carney, Michael E.
AU - Chang-Claude, Jenny
AU - Rossing, Mary Anne
AU - Harris, Holly R.
AU - Doherty, Jennifer Anne
AU - Risch, Harvey A.
AU - Khoja, Lilah
AU - Alimujiang, Aliya
AU - Phung, Minh Tung
AU - Brieger, Katharine
AU - Mukherjee, Bhramar
AU - Pharoah, Paul D.P.
AU - Wu, Anna H.
AU - Pike, Malcolm C.
AU - Webb, Penelope M.
AU - Pearce, Celeste Leigh
N1 - Publisher Copyright:
© 2020 The Author(s).
PY - 2021/3/1
Y1 - 2021/3/1
N2 - Background: Parity is associated with decreased risk of invasive ovarian cancer; however, the relationship between incomplete pregnancies and invasive ovarian cancer risk is unclear. This relationship was examined using 15 case-control studies from the Ovarian Cancer Association Consortium (OCAC). Histotype-specific associations, which have not been examined previously with large sample sizes, were also evaluated. Methods: A pooled analysis of 10 470 invasive epithelial ovarian cancer cases and 16 942 controls was conducted. Odds ratios (ORs) and 95% confidence intervals (CIs) for the association between incomplete pregnancies and invasive epithelial ovarian cancer were estimated using logistic regression. All models were conditioned on OCAC study, race and ethnicity, age, and education level and adjusted for number of complete pregnancies, oral contraceptive use, and history of breastfeeding. The same approach was used for histotype-specific analyses. Results: Ever having an incomplete pregnancy was associated with a 16% reduction in ovarian cancer risk (OR = 0.84, 95% CI = 0.79 to 0.89). There was a trend of decreasing risk with increasing number of incomplete pregnancies (2-sided Ptrend <. 001). An inverse association was observed for all major histotypes; it was strongest for clear cell ovarian cancer. Conclusions: Incomplete pregnancies are associated with a reduced risk of invasive epithelial ovarian cancer. Pregnancy, including incomplete pregnancy, was associated with a greater reduction in risk of clear cell ovarian cancer, but the result was broadly consistent across histotypes. Future work should focus on understanding the mechanisms underlying this reduced risk.
AB - Background: Parity is associated with decreased risk of invasive ovarian cancer; however, the relationship between incomplete pregnancies and invasive ovarian cancer risk is unclear. This relationship was examined using 15 case-control studies from the Ovarian Cancer Association Consortium (OCAC). Histotype-specific associations, which have not been examined previously with large sample sizes, were also evaluated. Methods: A pooled analysis of 10 470 invasive epithelial ovarian cancer cases and 16 942 controls was conducted. Odds ratios (ORs) and 95% confidence intervals (CIs) for the association between incomplete pregnancies and invasive epithelial ovarian cancer were estimated using logistic regression. All models were conditioned on OCAC study, race and ethnicity, age, and education level and adjusted for number of complete pregnancies, oral contraceptive use, and history of breastfeeding. The same approach was used for histotype-specific analyses. Results: Ever having an incomplete pregnancy was associated with a 16% reduction in ovarian cancer risk (OR = 0.84, 95% CI = 0.79 to 0.89). There was a trend of decreasing risk with increasing number of incomplete pregnancies (2-sided Ptrend <. 001). An inverse association was observed for all major histotypes; it was strongest for clear cell ovarian cancer. Conclusions: Incomplete pregnancies are associated with a reduced risk of invasive epithelial ovarian cancer. Pregnancy, including incomplete pregnancy, was associated with a greater reduction in risk of clear cell ovarian cancer, but the result was broadly consistent across histotypes. Future work should focus on understanding the mechanisms underlying this reduced risk.
UR - http://www.scopus.com/inward/record.url?scp=85102658101&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85102658101&partnerID=8YFLogxK
U2 - 10.1093/jnci/djaa099
DO - 10.1093/jnci/djaa099
M3 - Article
C2 - 32766851
AN - SCOPUS:85102658101
SN - 0027-8874
VL - 113
SP - 301
EP - 308
JO - Journal of the National Cancer Institute
JF - Journal of the National Cancer Institute
IS - 3
ER -