| Gestational Trophoblastic Disease
| | Type | Histologic Features | Clinical Features
|
| Complete Hydatidiform Mole | Composed of large, avascular villi with trophoblastic proliferation | Occurs when a fertilized ovum contains only paternal chromosomes (usually 46, XX karyotype); produces marked uterine enlargement; "snowstorm" effect with no fetus on ultrasonography; some give rise to choriocarcinoma
|
| Partial Hydatidiform Mole | Some villi are enlarged, with minimal trophoblast proliferation
| Typically are triploid (69, XXX or 69, XXY or 69, XYY); a malformed fetus is present that rarely goes to term; rarely gives rise to choriocarcinoma
|
| Choriocarcinoma | A malignant proliferation of syncytiotrophoblast with no villi; often hemorrhagic; no fetus is present
| HCG levels are often extremely high; can metastasize; many are sensitive to chemotherapy
|
| Placental Site Trophoblastic Tumor | A rare localized proliferation of intermediate trophoblast that can produce a grossly visible nodule | Most are bening; rare malignant cases
|
| Placental Site Nodule or Plaque | A rare proliferation of intermediate trophoblast that is microscopic | Of no major consequence
|
