2020 38 Gestational Trophoblastic Disease Flashcards
** What are the common signs & symptoms of molar pregnancies? **
- Irregular PV bleeding
- Positive pregnancy test
- Ultrasonographic evidence
** What are the less common presentations of molar pregnancies? **
- Hyperemesis
- Excessive uterine enlargement
- Hyperthyroidism
- Early-onset pre-eclampsia
- Abdominal distensión by theca lutein cysts
** What are the very rare presentations of molar pregnancy? **
- Haemoptysis due to lung mets
- Seizures due to brain mets
** How is molar pregnancy definitively diagnosed? **
Histology
** What method should be used for removal of a molar pregnancy? **
- Complete molar: suction curettage
- Consider US guidance to minimise chance of perforation or RPOC
- Partial molar: suction curettage unless fetal parts too big, then medical
** What surgical considerations are there for molar pregnancy removal? **
- Anti-D prophylaxis after
- Cervical preparation is safe
- Oxytocin infusion not recommended due to risk of tissue embolisation
- Senior consideration of oxytocin if significant haemorrhage
** When should repeat surgical removal be done for molar pregnancy? **
- Urgent if heavy or persistent PVB causing acute haemodynamic instability
- RPOC on USS
- If not acutely compromised, involve GTD referral centre
** How should GTD be excluded following miscarriage? **
- Histological assessment of all, if no fetal parts identified at any stage of pregnancy
- UPT at 3 weeks
** How should GTD be excluded following abortion? **
- No need to routinely send if fetal parts identified in prior USS
- UPT at 3 weeks
** How should elevated hCG after a possible pregnancy be managed? **
Referral to GTD centre, provided
1. Ectopic pregnancy excluded, or
2. 2 consecutive treatments with methotrexate
** Who should be investigated for GTN after a non-molar pregnancy? **
- Persistent PVB: urine hCG in all lasting more than 8 weeks
- Symptoms of mets including dyspnoea, haemoptysis, new onset seizures or paralysis
NB Do not biopsy secondary deposits in vagina as can cause major haemorrhage
** How should suspected ectopic molar pregnancy be managed? **
- As other ectopic pregnancy
- Send pregnancy tissue to a centre with appropriate expertise
** How is twin pregnancy of a viable fetus & coexistent molar managed? **
- If diagnosed or suspected, refer to FMU & GTD centre
- Counselling about increased risk of perinatal mortality
- Consider prenatal invasive testing: complete mole with coexisting normal vs singleton partial molar
- Also for suspected mesenchymal hyperplasia of placenta
** Which women should be registered at GTD centres? **
- Complete or partial molar
- Twin with complete or partial molar
- Limited macro or microscopic change suggesting early complete or partial molar or choriocarcinoma
- PSTT: placental site trophoblastic tumour
- ETT: epithelial trophoblastic tumour
- Atypical PSN: placental site nodule
** What is the optimum follow-up following a diagnosis of GTD? **
- Complete, hCG normal after 56 days ➡️ 6 months from uterine removal
- Complete, not normal after 56 days ➡️ 6 months from hCG normalisation
- Partial: after 2 normal hCG samples, > 4 weeks apart
** What is the optimum treatment for GTN? **
- Single-agent or multi-agent chemo
- Base Tx on FIGO 2000 scoring system
- PSTT & ETT less sensitive to chemo so treated surgically
** What are the recommendations for future pregnancy after GTD? **
- Do not TTC until follow-up complete
- > 1 year following chemotherapy
- Do not need histology or post-preg hCG from subsequent normal pregnancy if not treated for GTN
** What is the long-term outcome of women treated for GTN? **
- Overall cure rate close to 100%
- Further pregnancies in approx 80% following either methotrexate or multi-agent chemo
- Increased risk of premature menopause if combination agent chemo
** What are the implications of GTD for subsequent a) contraception, b) fertility drugs, c) HRT
a) most contraception OK, wait until hCG normalised before coil
b) fertility drugs safe once hCG normalised
c) HRT safe once hCG normalised
What are the premalignant conditions in GTD?
Complete mole
Partial mole
aka hydatidiform moles
What are the malignant conditions in GTD?
Invasive mole
Choriocarcinoma
Placental site trophoblastic tumour
Epithelial trophoblastic tumour
How is gestational trophoblastic neoplasia defined?
Persistence of GTD after primary treatment
Usually diagnosed by persistent β-hCG
What are the features of complete moles & how are they formed?
- Diploid & androgenic in origin
- No evidence of fetal tissue
- 75-80% single sperm, empty ovum
- 20-25% dispermic, empty ovum
What are the features of partial moles & how are they formed?
- 90% triploid, 2 sets paternal & 1 set maternal chromosomes
- Almost all dispermic fertilisation of single ovum
- Occasionally tetraploid or mosaic, but these aren’t necessary GTD
- Usually evidence of fetus or fetal red blood cells
What is the incidence of GTD, and how is it affected by extremes of age?
1: 714 live births
In age < 15, 1:500
In age > 50, 1:8
What is the incidence of gestational trophoblastic neoplasia?
1:50,000
What are the ultrasound features of a complete molar pregnancy?
5-7/40: polypoid mass
>8/40: thickened, cystic appearance of colloid tissue
No identifiable gestational sac
What are the ultrasound features of partial molar pregnancy?
Enlarged placenta
Cystic changes within decidual reaction
Associated with either empty sac or delayed miscarriage
What are the histological features of a complete mole?
- Absence of fetal tissue
- Extensive hydronic change to villi
- Excess trophoblast proliferation
What are the histological features of a partial mole?
- Presence of fetal tissue
- Focal hydronic change to villi
- Some excess trophoblast proliferation
Why is suction curettage recommended for all complete molars?
- No fetal parts so size doesn’t matter
- Risk of developing GTN 16x higher with medical management
- Potential to embolise
- Higher rate of incomplete removal with medical management
What is the incidence of GTD unrecognised prior to removal?
2.7%
What conditions other than pregnancy & GTD can cause raised β-hCG?
Familial raised hCG
Malignant female germ cell tumours
Epithelial cell tumours: bladder, breast, lung, gastric, colorectal
Pituitary hCG
Human anti-mouse antibodies
What are the risks for twins coexistent with GTD?
40% early fetal loss
36% premature birth
What is the risk of needing chemotherapy for GTN after molar pregnancies?
Complete: 13-16%
Partial: 0.5-1%
How is GTN managed with a FIGO 2000 score of ≤ 6?
IM methotrexate, alternated daily with folinic acid for 7 days, then 6 rest days
How is GTN with a FIGO score of ≥ 7 managed?
IV multi-agent chemotherapy:
1. Methotrexate
2. Dactinomycin
3. Etoposide
4. Cyclophoshphamide
5. Vincristine
Continue until normalised, then another 6 weeks
What features are scored in the FIGO 2000 scoring system?
- Age
- Type of pregnancy
- Interval since index pregnancy
- Pretreatment serum hCG
- Largest tumour size
- Site of metastases
- Number of metastases
- Previous failed chemotherapy
What are the cure rates for gestational trophoblastic neoplasia?
≤ 6: almost 100%
≥ 7: 94%
What are the future pregnancy risks following GTD?
- Repeat GTD: 1%
- Preterm birth: 25%
- LGA
- Stillbirth
