Objective--To investigate the strength of association between past lif
e events and the development of breast cancer. Design--Case-control st
udy. A standardised life events interview and rating was administered
before a definitive diagnosis. Setting--Breast Cancer Screening Assess
ment Unit and surgical outpatient clinics at King's College Hospital,
London. Subjects--119 consecutive women aged 20-70 who were referred f
or biopsy of a suspicious breast lesion. Main outcome measures--Odds r
atio of the risk of developing breast cancer after life events in the
preceding five years after adjustment for confounders. Results--41 wom
en were diagnosed as having malignant disease while the remainder had
benign conditions. Severe Life events increased the risk of breast can
cer. The crude odds ratio was 3.2 (95% confidence interval 1.35 to 7.6
). After adjustment for age and the menopause and other potential conf
ounders this rose to 11.6 (3.1 to 43.7). Multiple logistic regression
analysis showed that all severe events and coping with the stress of a
dverse events by confronting them and focusing on the problems signifi
cantly predicted a diagnosis of breast cancer. Non-severe life events
and long term difficulties had no significant association. Conclusion-
-These findings suggest an aetiological association between life stres
s and breast cancer.