Gestational trophoblastic disease Flashcards
What percent of GTDs are benign? What are they?
80% MOLAR PREGNANCIES aka. hydatidiform moles Complete mole (90%) partial mole (10%)
What percent of GTDs are malignant? What are they?
20%
Persistent/invasive mole (10-15%)
Choriocarcinoma (2-5%)
Placental site trophoblastic tumors (very rare)
Good thing about GTD for treatment?
Extremely sensitive to chemotherapy
Epidemiology
1/1000 pregnancies of white women. There’s a lower rate in black women in USA. Varies around the world.
HIGHEST AMONG ASIANS. (Japan 1/500)
Risk factors
- Extremes in age (women under 20 slightly, women over 35 a LOT…also have higher risk of MALIGNANT disease)
- Prior hx of GTD
- Nulliparity
- Diet low in beta-carotene, folic acid, animal fat
- Smoking, infertility, spontaneous abortion, blood group A, OCP use
Baseline risk? Risk in 1 prior? 2 prior?
Baseline is 0.1%
1 prior is 1%
2 prior is 16-28%
How does complete mole form? Chromo number?
- Empty egg, one normal sperm that DUPLICATES.
- All chromos paternally derived.
- 46,XX
Placental abnormality in complete mole?
NONINVASIVE trophoblastic proliferation, so the chorionic villi swell–> hydropic degeneration–> no fetal villy
Hormone disruptions in complete mole?
B-HCG unbelievably high (>100,000 mIU/mL) and its alpha subunit mimics TSH, LH, FSH.
The LH and FSH stimulation leads to LARGE THECA LUTEIN CYSTS
TSH leads to hyperthyroidism
B-HCG leads to hyperemesis gravidarum
Early preeclampsia
Do complete moles or partial moles have a higher malignant potential?
Complete moles (15-25%, 4% risk of mets)
Partial moles only have a 2-4% and NO risk of mets
How long do you follow up hCG levels with complete mole? Partial mole?
Complete is 14 wks
Partial is 8 wks
Presentation of a complete mole?
-Irregular or heavy bleeding during early pregnancy (b/c tumor separates from decidua)
Other: hyepremesis gravidarum, preeclampsia sx like irritability, dizziness, photophobia
Passage of molar vesicles 80% Anemia 50% Size greater than dates 30-50% Bilateral theca lutein cysts 25% Hyperthyroidism 10% Trophoblastic pulm embolic 2%
In someone who doesn’t have chronic hypertension, PREECLAMPISA BEFORE 20 WEEKS IS PATHOGNOMONIC FOR MOLAR PREGNANCY
Snowstorm pattern on u/s is CONFIRMATORY TEST.
Treatment for molar pregnancy?
- Immediate D&C
- Check Rh(D) status to prepare for possibly heavy vaginal bleeding during procedure
- Treat htn and hyperthyroidism with antihypertensives (dec risk of maternal stroke) and beta-blockers to avoid thyroid storm
- Have IV access and cross-matched blood available before the D&C
- GENERAL ANESTHESIA (due to hemorrhage risk and trophoblastic embolization risk)
-Give IV oxytocin immediately after to get uterus to contract and minimize blood loss
HYSTERECTOMY IS AN OPTION TOO
DO NOT GET PREGNANT WHILE THE HCG IS BEING MONITORED!!!
Do you care about administering RhoGAM in molar pregnancies?
YES!
Timing of serial hCG titers following D&C?
Within 48 hours.
Weekly until negative for 3 consecutive weeks.