Atypical Presentations of Molar Pregnancy: Diagnostic Roles of Imaging, β-Human Chorionic Gonadotropin Measurement, and p57 Immunostaining.

In modern practice , the diagnosis of molar pregnancy is made at an early gestational age. The opportunity to diagnose gestational trophoblastic disease (GTD) using sonography alone occurs less frequently. The classic appearance of a "snowstorm" in the endometrial cavity and bilateral theca lutein cysts still applies to the diagnosis of second-trimester GTD. The diagnosis of first-trimester GTD requires increased clinical suspicion. If the sonographic appearance of the pregnancy is atypical, GTD should be included in the differential diagnosis. Additional nonimaging criteria such as serial quantitative β-human chorionic gonadotropin levels, pathologic examination, and p57 (cyclin-dependent kinase inhibitor 1C protein) immunostaining can accurately confirm the diagnosis of GTD.