Expression of cyclin D1 in endometrial hyperplasia and endometrial carcinoma.

This study investigates the role of cyclin D1 in 30 uterine surgical resection and endometrial biopsy specimens from 30 patients with simple hyperplasia (10 cases), complex hyperplasia (6 cases) and endometrial carcinoma (14 cases). Cyclin D1 immunohistochemistry was performed on 2-4 mm thick paraffin sections using labelled streptavidin biotin kit. Cyclin D1 expression was present in 2/6 (33%) cases of complex hyperplasia, 7/14 (50%) cases of endometrial carcinoma and none in simple hyperplasia. Difference in cyclin D1 immunopositivity in simple hyperplasia and endometrial carcinoma was statistically significant (p = 0.018) but the difference in cyclin D1 immunopositivity between complex hyperplasia and endometrial carcinoma was not statistically significant. Our study suggests that cyclin D1 over-expression may be an early event in endometrial carcinogensis. Since there was no difference in extent and intensity of cyclin D1 expression between complex hyperplasia and endometrial carcinoma, it appears that deregulation is maximal in complex hyperplasia.