Abstract: Objective To investigate the bimolecular effects of tamoxifen on the uterine endometrium in women with breast cancer.Methods Using immunohistochemistry(LSAB) on formalin-fixed paraffin-embedded endometrial sections to study the variety of vascular endothelial growth factor(VEGF) in endometrium of postmenopausal patients with breast carcinoma who took tamoxifen more than two years and in endometral adenocarcinoma,with prolapse uterine endometrium as normal controls.Results The VEGF staining indices were significantly higher in endometrium of tamoxifen user and endometrial adenocarcinoma than in controls(P<0.05).The VEGF in the endometrium tamoxifen user was markedly increased, as much as that of endometrial adenocarcinoma.Conclusion The High-score of VEGF expression of the endometrium in women who have been treated with tamoxifen for breast cancer may be correlated with tamoxifen,which as the mechanism of oestrogen and anti-oestrogen action has the ability to affect the endometrium angiogenesis.Tamoxifen is able to induce pathological changes in endometrium.

Key words: vascular endothelial growth factor, endometrial adenocarcinoma, tamoxifen