Flow cytometric and clinicopathologic study of complete hydatidiform moles with special reference to the significance of cytometric aneuploidy

OBJECTIVE: As complete hydatidiform moles (CMs) have been studied less with respect to aneuploidy and its clinical implications, the significance of cytometric aneuploidy in CMs was evaluated. METHODS: Two hundred thirty-nine CMs were studied clinicopathologically and analyzed by flow cytometry using formalin-fixed paraffin-embedded tissues. RESULTS: Of 239 CMs, 182 were diploid, 30 were tetraploid, and 27 were aneuploid (nontriploid/tetraploid aneuploid). There were no significant histologic differences among the diploid, tetraploid, and aneuploid CMs. Persistent disease developed in 20 of 114 CMs (17.6%) (16 of 77 diploid, 4 of 18 tetraploid, and none of 19 aneuploid CMs). Eight diploid and three tetraploid CMs were invasive, and one patient each with diploid CM and tetraploid CM developed choriocarcinoma and none of 19 patients with aneuploid CMs had sequelae. CONCLUSION: These results suggest that aneuploid CMs are associated with less risk for persistent disease than diploid or tetraploid CMs. DNA ploidy status may be an independent predictor of persistent disease.