XY and XX complete moles: clinical and morphologic correlations.

The results of clinical, morphologic, and histologic analysis of nine XY complete moles (six karyotyped, three Y-chromatin positive) were compared with the results from analysis of 16 XX moles. Five of the nine XY moles were proved to result from dispermy while all the 16 XX moles studied originated from the doubling of a haploid sperm. At follow-up delayed decrease or rebound of urinary (or serum) human chorionic gonadotropin levels was noted in three of eight women with XY moles and in five of 15 women with XX moles. One woman with an XY mole was treated for lung metastasis, but her condition remained stable over a 4-year follow-up period. No appreciable difference was noted in the gross and microscopic findings between the XY and XX moles. On the other hand, differences were noted between younger (12 weeks or less of menstrual age) and older (13 weeks or more) moles. Younger moles had smaller, elliptic or club-shaped villi with numerous secondary villous sprouts, poorly demarcated central cisternae, and frequent mesenchymal capillaries. Older moles had larger, oval or globular villi with sparse villous sprouts, well-developed central cisternae, and less frequent remnants of capillaries. Trophoblastic hyperplasia was more marked in older than in younger moles.