Flow cytometric analysis of cellular DNA and RNA contents of hydatidiform mole. Two significant parameters indicating malignant nature and prognosis.

The cellular DNA and RNA contents of trophoblastic tissue of 86 patients with trophoblastic disease and chorionic tissue of 10 patients in early pregnancy were analysed by flow cytometry (FCM) and strict follow-up was carried out. The result showed the rate of accurate diagnosis by DNA and RNA determinations were 60.0% and 85.7% respectively in benign moles; 86.7% and 86.7% in invasive moles; and 100% and 100% in choriocarcinoma. Statistically the pseudopositive percentage of RNA was clearly lower than that of DNA (0.01 < P < 0.05). In addition, the trophoblastic cells in curetted molar tissue and the uterine tissue later proved by surgery of 10 invasive moles were simultaneously assayed for comparing their DNA and RNA contents, showing statistical significance (P < 0.001). The DNA and RNA contents in different cellular cycles were analysed by FCM and there was no statistical significance among benign, malignant moles and choriocarcinoma (P > 0.05). Our study suggests that aneuploidy DNA content may be an indicator for malignant tendency and the RNA parameter rather than DNA is more sensitive for the prognosis of hydatidiform mole.