How is morphology of hydatidiform mole?

➢ In advanced cases the uterine cavity is expanded by a delicate, friable mass of thin-walled, translucent cystic structures. ➢ Fetal parts are rarely seen in complete moles but are common in partial moles. ➢ On microscopic examination, the complete mole shows hydropic swelling of poorly vascularized chorionic villi with a loose, myxomatous, edematous stroma. ➢ The chorionic epithelium typically shows a proliferation of both cytotrophoblasts and syncytiotrophoblasts . ➢ Histologic grading to predict the clinical outcome of moles has been supplanted by monitoring of hCG levels ➢ In partial moles, villous edema involves only a subset of the villi, and the trophoblastic proliferation is focal and slight. ➢ In most cases of partial mole, some fetal cells are present, ranging from fetal red cells in placental villi to, in rare cases, a fully formed fetus. ➢ Overall, 80% to 90% of moles do not recur after thorough curettage, but 10% of complete moles are invasive. ➢ No more than 2% to 3% give rise to choriocarcinoma.