Purpose: to evaluate the effects of tamoxifen on the expression of TGF-beta and p27 proteins in polyps and adjacent endometrium of women after menopause.
Methods: prospective study with 30 post-menopausal women with diagnosis of breast cancer, taking tamoxifen (20 mg/day), presenting diagnosis of suspect endometrial polyps through transvaginal ultrasonography, and submitted to diagnostic and surgical hysterectomy to withdraw the polyps and adjacent endometrium. A immunohistochemical study has been done to verify the expression of the TGF-beta and p27 proteins in the polyps and adjacent endometrium. These proteins' quantification has been done by morphometry.
Results: the patients' average age was 61.7 years old; their average age at the menopause onset was 49.5; and the average of using tamoxifen was 25.3 months. The average concentration of positive cells for TGF-beta protein in the glandular and stroma polyp epithelium was 62.6+/-4.5 cells/mm(2). For the p27, in the glandular polyp epithelium, it was 24.2+/-18.6 cells/mm(2) and for the stroma, 19.2+/-15.2 cells/mm(2). There was no significant difference between the expression of TGF-beta and p27 in the glandular epithelial form the polyps and the adjacent endometrium. The expression of proteins in the polyp and adjacent endometrium with its respective glandular and stroma epithelium showed a significant difference for the p27 protein (r=0.9, p<0.05).
Conclusions: we have concluded that the TGF-beta expression is not related to the effect of tamoxifen on the growing of endometrial polyps, but the absence of polyps' malignization by tamoxifen may be explained by the high expression of p27 protein in its glandular epithelium.