Enzymohistochemical study on the gestational choriocarcinoma: histochemistry of choriocarcinoma

Histochemical investigation of Al-p, HSAP, Ac-p, and LDH was performed with tissues of normal chorionic villi, H. mole, invasive mole, and choriocarcinoma with the following conclusions: 1. In the normal villous tissues, Al-p, HSAP, and Ac-p are localized in syncytiotrophoblast, the former two in the rim of the cell, and the latter inside the cytoplasm. LDH displayed higher activity in cytotrophoblast than syncytiotrophoblast, especially in the former of cell column of initial chorionic villi. 2. In H. mole, Al-p, HSAP, and Ac-p are localized in syncytiotrophoblast of cystic epithelium, and in this layer and transitional cells of the chrioblastic part, the former two are localized in the rim of the cell, the latter within the cytoplasm. LDH is localized in cytotrophoblast and the transitional cell of the cystic epithelium and the chorioblastosis. 3. Localization and activities of Al-p, HSAP, Ac-p, and LDH in invasive mole are closely similar to those in H. mole. 4. Localization and activities of Al-p, HSAP, and Ac-p in choriocarcinoma presented various aspects, but more frequently they are localized in syncytiotrophoblasts in the periphery of focus and also partly in cytotrophoblasts and transitional cells. Also localization and activity of LDH showed diversity. However, the activity is stronger in cytotrophoblast. 5. From those findings, choriocarcinoma is hardly comparable with H. mole or invasive mole from an enzymohistochemical viewpoint and is assumed to have specific enzymic deviation invisible in the others and therefore to possess particular characteristics different from those of any other villous tissues.