This study aimed to determine the utility of post-evacuation transvaginal ultrasound as an adjunct to serum ß-hCG monitoring of patients diagnosed with hydatidiform mole. It is a prospective cohort analysis of 13 patients diagnosed with hydatidiform mole who underwent suction curettage from December 1, 2010 to February 28, 2011 at the Philippine General Hospital. Transvaginal ultrasound immediately post-evacuation of hydatidiform mole and then monthly thereafter were performed. The morphologic characteristics of the uterus and ovaries were observed and recorded during each examination. The usual monitoring protocol of hydatidiform mole after evacuation of molar products which is serial serum ß-hCG was observed. The serum ß-hCGlevels and the results of the transvaginal ultrasound scans were correlated during data analysis.
Data were analyzed using STATCALC version 2000.Traditional calculations for the sensitivity, specificity, positive and negative predictive values for each sonographic descriptor was conduced with their 95% confidence intervals derived. All P-values less than .05 were considered statistically significant.
Two of the 13 (15.4%) patients with complete hydatidiform mole progressed to gestational trophoblastic neoplasia (GTN).In this study, the presence of uterine mass with increased vascularity and low resistance indices on color Doppler studies was the most accurate in predicting the progression of hydatidiform mole to GTN with a high specificity (90.9%)and sensitivity (100%).Interestingly, the uterine mass was noted even before the rise in the serum ß-hCG levels. The other sonographic features observed post-evacuation of hydatidiform mole include: dilated arcuate vessels, theca lutein cysts and hematometra.
This study demonstrated that transvaginal ultrasound is essential in the diagnosis of hydatidiform mole as well as as in the follow-up of patients post-evacuation of molar tissues and in predicting the degeneration of hydatidiform mole to GTN. Clinical use of its predictive value permits individualization of follow-up and a timely and appropriate management or referral of patients for treatment prior to the onset of advanced stage of disease.