Bleeding in early pregnancy: Gestational trophoblastic disease Flashcards
GTD
Tumours that arise from products of conception
- Invasive vs non-invasive
Types of GTD
Invasive (aka GTN)
- Invasive mole
- Choriocarcinoma
- Placental site trophoblastic tumour
Non-invasive
- Hydatidiform moles (partial vs complete)
Risk factors of developing GTD
Extremes of maternal age
History of previous GTD
Complete mole
Duplication of single haploid sperm following fertilization of empty ovum
-> Diploid
Absent fetal tissue
Karyotype: 46XX, 46XY
Clinical features of complete mole
Due to high levels of circulating hCG:
- Abnormal vaginal bleeding (prune juice)
- Pre-eclampsia
- Hyperthyroidism
- Excessive N/V (hyperemesis gravidarum)
- Uterine size large than dates
- Enlarged ovarian cyst
PE: accordingly to ^
Ultrasound findings of complete mole
Snowstorm appearance of endometrium
Multiple vesicles “cluster of grapes”
Enlarged ovarian cysts
Absent fetus
Risk of progression for complete mole
15% risk of becoming invasive mole
4% risk of choriocarcinoma
Partial mole
Dispermic fertilisation of an ovum
-> triploid
Present fetal tissue
Karyotype: 69XXY, 69XYY
*2 sets of paternal haploid genes + 1 set of maternal haploid gene
Clinical features of partial mole
Presents as missed miscarriage or incomplete miscarriage
*U/S features corresponds accordingly ^
Risk of progression for partial moles
2-4% risk of persistence
Rare for malignant transformation
Ultrasound findings in partial mole
Honeycomb placenta + presence of peanut looking structure (fetal tissue present)
complete mole NO fetus (no fetus tissue)
Management of molar pregnancy
- Suction curettage or Hysterectomy
- Send POC for histological examination
Risk of incomplete evacuation
Risk of asherman’s syndrome
Risk of uterine perforation!
Postop surveillance
- Weekly serum HCG until 3 consecutive results are negative, then monthly for 6 months
- Advise patient for contraception until HCG levels revert to normal to not be confused with new pregnancy (COCP best option)
- Avoid IUCD until HCG levels revert to normal to reduce risk of uterine perforation
- Risk of further molar pregnancy is 1 in 80
What HCG levels is suggestive of invasive mole post molar pregnancy
Persistent elevated beta-hCG levels after molar evacuation
- plateau or rising
Gestational trophoblastic Neoplasm
- Can follow ANY gestational event**
- More likely to follow COMPLETE MOLE
- If GTN after a non-molar pregnancy: likely choriocarcinoma (most aggressive)
- 10x more likely after spontaneous miscarriage than term pregnancy
- Usually locally invasive and seldom metastatic (unless post non-molar pregnancy due to delayed diagnosis)
Clinical features of GTN
Chorionic proliferation
- Uterine size larger than dates
- HCG > 100,000
- Ovarian cysts (theca lutein)
Prior gestational event
Prior hx of molar pregnancy
Systemic
- Neuro
- SCN
- Breast
- Abdomen
- Pelvic (large uterus, adnexal masses)
- Vagina
- METS to lungs, vagina (hematogenous spread)
What is the mode of metastatic spread of GTN and to which organ(s)?
Hematogenous spread to lungs, vagina
Is histological dx required before starting treatment for GTN?
No. Only cancer that does not require histological dx before starting treatment.
- Just initiate chemotherapy if HCG remains persistent/rising
HCG levels suggestive of GTN post molar pregnancy
- Rise of HCG on 3 consecutive weekly measurements
- Plateauing of HCG levels for 3 or more weeks
- HCG levels remain elevated for 6 months or more
Investigations to do for GTN
- serial HCG levels
- Ultrasound
- CXR for lung mets
What important organ to check for mets?
CXR for LUNG mets
Staging of GTN
Figo staging of GTN
I: Confined to uterine corpus
II: Adnexa, vagina
III: Lungs
IV: Outside of lungs, vagina or pelvis
Treatment of GTN
- Mainstay is chemotherapy
- Methotrexate or D-actinomycin
- Consider multiple agent chemotherapy - Hysterectomy
Prognosis of GTN
Very good for most patients and can retain fertility
Choriocarcinoma
somewhat an exception
- Most agressive GTN
- Commonly FIGO stage IV
- Chemotherapy with multiple agents
Difference between invasive mole, choriocarcinoma VS placental site trophoblastic tumour
Invasive mole, choriocarcinoma:
- HIGH HCG, EARLY Dx
Placental site trophoblastic tumour:
- LOW HCG, LATE Dx
Placental site trophoblastic tumour
- hCG levels not elevated (not a good marker)
- Usually indolent, slow-growing, mets only in the late stages
- Not chemosensitive
- Requires hysterectomy as mainstay of treatment
Investigations for GTD
- Vitals (BP - Pre-eclampsia, RR, HR, SpO2)
- FBC to check Hb
- GXM
- Blood group + Rh status for anti-D prophylaxis
*Give RhoGAM to partial moles only bc it has fetal parts (Complete has no fetal parts) - UECr TRO electrolyte disturbances especially if N&V
- TFT even if patient asymptomatic due to risk of intra-op thyroid storm (Molar pregnancy-indued hyperthyroidism/ thyrotoxicosis)
- Beta-hCG levels preop and postop for f/u (Tumor marker)
