Risk of breast cancer was assessed in relationship to gynecologic operations using data from a record-linkage study involving 15,844 women in the Uppsala Health Care Region of Sweden, who underwent surgery between 1965 and 1983.
Data abstracted from medical records for the breast cancer cases and a random sample of the cohort allowed examination of risk associated with these operations in regard to menopausal status and indications for the operations.
Among women who were pre-menopausal at the time of operation, a bilateral oophorectomy before the age of 50 years was associated with a 50% reduction in the risk of breast cancer compared with the background population, a reduction in risk evident within 10 years of the operation.
A bilateral oophorectomy after the age of 50 years in pre-menopausal women or after a natural menopause was not associated with any reduction in risk.
There were no reductions in risk associated with a unilateral oophorectomy or hysterectomy among women who were pre-menopausal at the time of operation.
In fact, hysterectomy alone was associated with a slight increase in breast cancer risk when the operation was due to myomas, abnormal bleeding, and, possibly, severe forms of endometriosis but not to other reasons.
Risk did not vary substantially by indications for oophorectomy, including benign ovarian neoplasms and functional ovarian cysts, though endometriosis was associated with a non-significant increase in breast cancer risk.
Mots-clés Pascal : Appareil génital femelle pathologie, Homme, Femelle, Ovariectomie, Hystérectomie, Age, Tumeur maligne, Glande mammaire, Epidémiologie, Analyse risque, Suède, Europe, Echelon régional, Etude longitudinale, Etude cohorte, Chirurgie, Glande mammaire pathologie
Mots-clés Pascal anglais : Female genital diseases, Human, Female, Ovariectomy, Hysterectomy, Age, Malignant tumor, Mammary gland, Epidemiology, Risk analysis, Sweden, Europe, Regional scope, Follow up study, Cohort study, Surgery, Mammary gland diseases
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0181255
Code Inist : 002B20E02. Création : 21/05/1997.