Diagnostic Ultrasound - Abdomen and Pelvis

Gestational Trophoblastic Disease
Diagnoses: Female Pelvis
IMAGING
• Hydatidiform moles
○ Partial hydatidiform mole: Thickened placenta with
cystic change and peripheral vascularity, may be
associated with fetal parts
○ Complete hydatidiform mole: Enlarged placenta with
multiple cysts
– "Snowstorm" appearance or "bunch of grapes"
– No embryo
• Malignant Gestational Trophoblastic Disease
○ Invasive mole: Heterogeneous intrauterine mass with
extension into myometrium
○ Choriocarcinoma: Heterogeneous uterus with complex
hypervascular mass invading myometrium and
extrauterine extension
○ Placental site trophoblastic tumor: Intrauterine
echogenic mass with myometrial involvement and
extrauterine extension
KEY FACTS
TOP DIFFERENTIAL DIAGNOSES
• Placental hydropic degeneration
• Placental sonolucencies (pseudomole)
• Retained products of conception (RPOC)
• Androgenic biparental mosaicism with placental
mesenchymal dysplasia (PMD)
PATHOLOGY
• Partial mole (triploidy)
○ Karyotypes: 69,XXY (most common); 69,XXX; 69,XXY
• Complete hydatidiform mole
○ 46, XX more common than 46, XY
○ No fetal tissue present
CLINICAL ISSUES
• ↑ risk at extremes of reproductive age
(Left) Coronal color Doppler
US through the uterine body
shows a partial molar
pregnancy. Note the empty
irregular gestational sac
and associated enlarged
placenta with cystic
components ſt. (Right)
Transverse grayscale US of a
partial mole shows an
intrauterine gestation with
fetal pole . No fetal cardiac
activity was seen in real-time.
The placenta is markedly
thickened and echogenic in
appearance, greater than
expected for gestational age.
(Left) Gross pathology of a
partial molar placenta shows
typical trophoblastic hydropic
villi and cluster of molar
vesicles , compatible with a
"cluster of grapes"
appearance. (Right)
Longitudinal color Doppler US
of a complete hydatidiform
mole shows a heterogeneous
multicystic mass
resembling a "cluster of
grapes." Note that the
multicystic areas are relatively
avascular, a helpful clue to
differentiate from an invasive
mole.
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