Use of monoclonal antibodies MSN-1 and B72.3 in the prediction of the natural history of endometrial hyperplasia.

Forty patients, originally diagnosed as endometrial hyperplasia, were reviewed histopathologically and evaluated for immunohistochemical staining with antibodies directed against TAG-72 and MSN-1 antigens. All patients had follow-up endometrial biospies or hysterectomies from 1 to 13 years later. The extent of regression to normal of nonhyperplastic endometrium, persistence as any type of endometrial hyperplasia, or progression to endometrial adenocarcinoma was correlated with the histologic hyperplastic subtype and immunohistochemical staining. As expected, cases of complex or atypical hyperplasia more often progressed to carcinoma than cases of simple or no hyperplasia. Interestingly, MSN-1 positivity was more prevalent in cases of higher grades than lower grades of hyperplasia and was associated with the tendency to show persistent hyperplasia or progression to carcinoma. B72.3 positivity was uncommon in the hyperplastic endometrium and was not correlated with clinical regression or progression. Although the tendency for progression of endometrial hyperplasia to endometrial carcinoma is best judged histologically, MSN-1 may add prognostic information in subgroups of hyperplasia.