Breast cancer risk and ovariectomy, hysterectomy, and tubal sterilization in the women's contraceptive and reproductive experiences study.
Removal or impairment of ovaries before menopause may affect a woman's breast cancer risk by altering her cumulative exposure to ovarian hormones. The Women's Contraceptive and Reproductive Experiences Study, a population-based, multicenter case-control study of incident invasive breast cancer, recruited women aged 35-64 years (4,490 cases and 4,611 controls) who provided data on ovariectomy, hysterectomy, and tubal sterilization during in-person interviews. Controls were frequency-matched to cases by age, race, and study site. Unconditional logistic regression analysis was used. Women who had not undergone premenopausal reproductive surgery were the referent group. Bilateral ovariectomy was associated with reduced breast cancer risk overall (odds ratio (OR) = 0.59, 95% confidence interval (CI): 0.50, 0.69) and among women <45 years of age (ORs ranged from 0.31 to 0.52), but not among those who were older at surgery. It was also associated with a reduced risk for estrogen and progesterone receptor-positive tumors (OR = 0.63, 95% CI: 0.52, 0.75) but not receptor-negative tumors. Hysterectomy with ovarian conservation (OR = 0.83, 95% CI: 0.72, 0.96) and hysterectomy with partial ovary removal (OR = 0.73, 95% CI: 0.59, 0.91) were also associated with lower risk. No association with breast cancer risk was observed with tubal sterilization only or partial ovariectomy without hysterectomy. Reproductive organ surgeries may alter ovarian hormone levels, thereby affecting breast cancer risk.
Department of Preventive Medicine, Keck School of Medicine, and Norris Comprehensive Can-cer Center, University of Southern California, Los Angeles, California, USA.
David J
DJ
Press
Jane
J
Sullivan-Halley
Giske
G
Ursin
Dennis
D
Deapen
Jill A
JA
McDonald
Brian L
BL
Strom
Sandra A
SA
Norman
Michael S
MS
Simon
Polly A
PA
Marchbanks
Suzanne G
SG
Folger
Jonathan M
JM
Liff
Ronald T
RT
Burkman
Kathleen E
KE
Malone
Linda K
LK
Weiss
Robert
R
Spirtas
Leslie
L
Bernstein
D000328:Adult; D000367:Age Factors; D001943:Breast Neoplasms / Q000453:epidemiology* / Q000209:etiology; D003267:Contraception / Q000009:adverse effects* / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007044:Hysterectomy / Q000009:adverse effects* / Q000706:statistics & numerical data; D015994:Incidence; D008875:Middle Aged; D010052:Ovariectomy / Q000009:adverse effects* / Q000706:statistics & numerical data; D017584:Reproductive History; D012307:Risk Factors; D013246:Sterilization, Tubal / Q000009:adverse effects* / Q000706:statistics & numerical data; D014481:United States / Q000453:epidemiology