Quantitative morphology

It is difficult to predict the possible development of a malignant trophoblastic tumor after the evacuation of a hydatidiform mole. In order to help resolve this difficulty, a morphometric study has been carried out. The mean nuclear area of the trophoblast in a group of hydatidiform moles, followed by a trophoblastic malignancy, was found to be statistically significantly larger than that of the trophoblast in a group of hydatidiform moles which were not followed by malignant trophoblastic disease. However, the mean trophoblast/nontrophoblast ratio in villi demonstrated no statistically significant difference between those 2 groups of hydatidiform moles. Therefore it is not advisable to grade hydatidiform moles on the basis of trophoblastic proliferation alone.