Gestatational trophoblastic disease: multimodality imaging assessment with special emphasis on spectrum of abnormalities and value of imaging in staging and management of disease.

Gestational trophoblastic disease is a spectrum of disorders of varying malignant potential arising from trophoblastic cells and encompassing hydatidiform moles and persistent trophoblastic neoplasia. Ultrasound is the initial imaging investigation of choice when gestational trophoblastic disease is suspected. Complete hydatiform mole, the most common form of molar pregnancy, usually has a characteristic "cluster of grapes" appearance, especially on second-trimester ultrasounds. Persistent trophobastic neoplasia usually appears as a focal, hypervascular myometrial mass on pelvic ultrasound. Pelvic magnetic resonance imaging is often used as a problem-solving tool in equivocal or complicated cases of gestational trophoblastic disease to assess the degree of invasion into the myometrium and surrounding tissues. Chest x-ray, brain magnetic resonance imaging, and body computed tomography scans are primarily used for the evaluation of metastatic disease, which usually occurs in the context of choriocarcinomas. Choriocarcinoma metastases are usually hypervascular and have a tendency to bleed, features that are reflected in their imaging appearance.