Hydatidiform mole will progress to malignant gestational trophoblastic neoplasia (GTN) in some cases. Aneuploidy and high proliferative activity are associated with malignant tumors. Molar pregnancy tissue was considered a precursor to malignant GTN, and was studied retrospectively using paraffin-embedded tissue to determine whether aneuploidy or proliferative rates measured on molar tissue could predict a malignant course. Tissues from 51 complete hydatidiform moles were analyzed for nuclear DNA content by flow cytometric techniques. A chart review identified the clinical course after evacuation of the mole. A satisfactory DNA histogram was generated in 40 cases. Of the 40 patients, 22 (55%) had spontaneous resolution, and 18 patients (45%) required treatment for persistent GTN. The molar tissue was found to be euploid in 27 cases and aneuploid in 13 cases. Eight of the twenty-seven euploid cases (30%) required treatment after evacuation, whereas 10 of the 13 aneuploid cases (77%) required treatment after molar evacuation. Proliferative index (PI) was compared with treatment requirements. Average PI was 0.11 ±0.10 for the treatment group and 0.08 ± 0.06 for the spontaneous resolution group. The correlation of clinical course with ploidy was significant (P < 0.01). The association with proliferative index was not (P > 0.05). Aneuploidy, therefore, identifies a high-risk group of molar pregnancies, and may represent those that have undergone one stage of malignant transformation.
ASJC Scopus subject areas
- Obstetrics and Gynecology