Maspin expression, subcellular localization and clinicopathological correlation in endometrial hyperplasia and endometrial adenocarcinoma.

Maspin expression in endometrial hyperplasia and endometrial endometrioid adeno-carcinomas was assessed and its correlation with p53 and Ki-67 expressions and clinical outcome, as well as its potential to distinguish typical from atypical endometrial hyperplasia, were assessed in this study. Histological sections from 114 cases of endometrial endometrioid adenocarcinoma, 75 cases of endometrial hyperplasia (typical and atypical), and 23 normal endometrial tissue samples were examined. The most representative hematoxylin-eosin slides were selected and 2-3 micron-thick sections were cut for immunohistochemical staining with maspin, p53, and Ki-67 antibodies. While there was no maspin expression in normal endometrial cells, it was present in 14.5% of the patients with endometrial hyperplasia without atypia. Staining for maspin was positive in atypical hyperplasia and endometrial adenocarcinoma in, respectively, 45% and 49.1% of the cases studied. No statistically significant correlations were found between maspin and Ki-67 antibodies or p53 expression. Our findings showed that maspin expression, which generally correlates with a less aggressive behavior, is significantly higher in atypical hyperplasia and in endometrial endometrioid adenocarcinoma. Maspin positivity in endometrial hyperplasia could be used to identify pseudo-atypical hyperplasia and could be considered a potentially useful prognostic parameter in those cases in which adenocarcinomas are well differentiated.