[The significance of alpha-fetoprotein-negativity in the interstitial area of total hydatidiform mole tissue].

UNLABELLED: The presence of the fetal component is an important factor in explaining the mechanism of the occurrence of the hydatidiform mole. But we have not confirmed in which phase the fertilized becomes a fetus. Therefore the mechanism of the occurrence of hydatidiform mole was investigated, using alpha-fetoprotein (AFP) produced in the fetal liver and the yolk sac, as a parameter. Total hydatidiform moles, partial hydatidiform moles, chorionic villi obtained from normal pregnancy artificially terminated and spontaneous abortion, and also the fetal liver, umbilical cord, and intestine were examined. Paraffin sections of these materials were examined for the presence of AFP by a peroxidase-anti-peroxidase method.

RESULTS: In the fetal liver, the gelatinous area of the umbilical cord the lamina propria mucosae of the intestine, and the AFP were stained positive. In the interstitial area of the chorionic villi of normal pregnancy, the AFP was positive (78.3% n = 23). But in the villous epithelium, the AFP was negative. In the interstitial area of the chorionic villi of spontaneous abortion, the AFP was positive (88.9% n = 9). But in the villous epithelium, the AFP was negative. In the interstitial area of the partial hydatidiform mole, the AFP was positive (100% n = 6). In the epithelial area, the AFP was negative. No localization of the AFP was found in either the interstitial area or the epithelial area of the cyst of total hydatidiform mole (100% n = 7). We concluded that the AFP exuded to tissues derived from mesoblast by feto-chorionic circulation.(ABSTRACT TRUNCATED AT 250 WORDS)