To investigate whether breast tumors developing through a pathway with p53 protein overexpression (p53+) show different risk factor associations compared with breast tumors without p53 overexpression (p53-), the authors determined p53 overexpression in tissue sections of 528 patients with invasive breast cancer by using immunohistochemistry.
These patients and 918 healthy controls aged 20-54 years participated in a Netherlands population-based case-control study on oral contraceptives in 1986-1989.
A total of 142 tumors (27%) demonstrated clear p53 overexpression (p53+). Most risk factors did not show different associations with p53+and p53-tumors.
However, use of oral contraceptives for 9 or more years was associated with a 2.5-fold increase in the risk of p53+tumors (95% confidence interval 1.4-4.4 ; test for trend with months of use, p=0.01), whereas such use increased the risk of p53-tumors only 1.4-fold (95% confidence interval 0.9-2.1 ; test for trend, p=0.06).
Prolonged lactation (=25 weeks) was associated with a 40% reduction in risk of p53+tumors (odds ratio=0.6 ; 95% confidence interval 0.3-1.0 ; test for trend with weeks of lactation, p=0.09), whereas the risk of p53-tumors was not associated with lactation. (...)
Mots-clés Pascal : Tumeur maligne, Glande mammaire, Immunohistochimie, Facteur risque, Epidémiologie, Homme, Glande mammaire pathologie, Protéine p53
Mots-clés Pascal anglais : Malignant tumor, Mammary gland, Immunohistochemistry, Risk factor, Epidemiology, Human, Mammary gland diseases, Protein p53
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 97-0031187
Code Inist : 002B20E02. Création : 21/05/1997.