Immunohistochemical localization of placental proteins and tumor-associated antigens in endometrial cancer and endometrial hyperplasia.

As to endometrial cancer and endometrial hyperplasia, this study represents the localizations of the placental proteins and the tumor-associated antigens by both immunohistochemical light microscopy (ILM) and immunoelectron microscopy (IEM). The reagents examined include human placental lactogen (HPL), placental alkaline phosphatase (PAP), pregnancy-associated plasma protein A (PAPP-A), pregnancy-specific beta 1-glycoprotein (SP1), alpha 1-anti-trypsin (alpha-AT), and tissue polypeptide antigen (TPA). The tumor cells stained for HPL are localized and the SP1-positive cancer cells are almost entirely restricted to an infiltrating front. alpha-AT is shown in both tumor cells with marked cellular atypism and ones in deeply infiltrating foci. The immunoreactive frequency for the above six reagents in endometrial cancer is higher than that in endometrial hyperplasia. In endometrial cancer, the high frequency of an immunoreaction is confirmed in TPA (p less than 0.05). The combined stainings, i.e. either for TPA and SP1 or for TPA and PAPP-A, are efficient immunohistochemical screening methods to use in diagnosing endometrial cancer in the biopsied specimens (p less than 0.05).