Bleeding in early pregnancy: Gestational trophoblastic disease

Question 1

GTD

Answer 1

Tumours that arise from products of conception
- Invasive vs non-invasive

Question 2

Types of GTD

Answer 2

Invasive (aka GTN)
- Invasive mole
- Choriocarcinoma
- Placental site trophoblastic tumour

Non-invasive
- Hydatidiform moles (partial vs complete)

Question 3

Risk factors of developing GTD

Answer 3

Extremes of maternal age
History of previous GTD

Question 4

Complete mole

Answer 4

Duplication of single haploid sperm following fertilization of empty ovum
-> Diploid
Absent fetal tissue
Karyotype: 46XX, 46XY

Question 5

Clinical features of complete mole

Answer 5

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 ^

Question 6

Ultrasound findings of complete mole

Answer 6

Snowstorm appearance of endometrium
Multiple vesicles “cluster of grapes”
Enlarged ovarian cysts
Absent fetus

Question 7

Risk of progression for complete mole

Answer 7

15% risk of becoming invasive mole
4% risk of choriocarcinoma

Question 8

Partial mole

Answer 8

Dispermic fertilisation of an ovum
-> triploid
Present fetal tissue
Karyotype: 69XXY, 69XYY

*2 sets of paternal haploid genes + 1 set of maternal haploid gene

Question 9

Clinical features of partial mole

Answer 9

Presents as missed miscarriage or incomplete miscarriage

*U/S features corresponds accordingly ^

Question 10

Risk of progression for partial moles

Answer 10

2-4% risk of persistence
Rare for malignant transformation

Question 11

Ultrasound findings in partial mole

Answer 11

Honeycomb placenta + presence of peanut looking structure (fetal tissue present)

complete mole NO fetus (no fetus tissue)

Question 12

Management of molar pregnancy

Answer 12

• Suction curettage or Hysterectomy
• Send POC for histological examination

Risk of incomplete evacuation
Risk of asherman’s syndrome
Risk of uterine perforation!

Question 13

Postop surveillance

Answer 13

• 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

Question 14

What HCG levels is suggestive of invasive mole post molar pregnancy

Answer 14

Persistent elevated beta-hCG levels after molar evacuation
- plateau or rising

Question 15

Gestational trophoblastic Neoplasm

Answer 15

• 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)

Question 16

Clinical features of GTN

Answer 16

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)

Question 17

What is the mode of metastatic spread of GTN and to which organ(s)?

Answer 17

Hematogenous spread to lungs, vagina

Question 18

Is histological dx required before starting treatment for GTN?

Answer 18

No. Only cancer that does not require histological dx before starting treatment.
- Just initiate chemotherapy if HCG remains persistent/rising

Question 19

HCG levels suggestive of GTN post molar pregnancy

Answer 19

1. Rise of HCG on 3 consecutive weekly measurements
2. Plateauing of HCG levels for 3 or more weeks
3. HCG levels remain elevated for 6 months or more

Question 20

Investigations to do for GTN

Answer 20

1. serial HCG levels
2. Ultrasound
3. CXR for lung mets

Question 21

What important organ to check for mets?

Answer 21

CXR for LUNG mets

Question 22

Staging of GTN

Answer 22

Figo staging of GTN
I: Confined to uterine corpus
II: Adnexa, vagina
III: Lungs
IV: Outside of lungs, vagina or pelvis

Question 23

Treatment of GTN

Answer 23

1. Mainstay is chemotherapy
   - Methotrexate or D-actinomycin
   - Consider multiple agent chemotherapy
2. Hysterectomy

Question 24

Prognosis of GTN

Answer 24

Very good for most patients and can retain fertility

Question 25

Choriocarcinoma

Answer 25

somewhat an exception
- Most agressive GTN
- Commonly FIGO stage IV
- Chemotherapy with multiple agents

Question 26

Difference between invasive mole, choriocarcinoma VS placental site trophoblastic tumour

Answer 26

Invasive mole, choriocarcinoma:
- HIGH HCG, EARLY Dx

Placental site trophoblastic tumour:
- LOW HCG, LATE Dx

Question 27

Placental site trophoblastic tumour

Answer 27

• 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

Question 28

Investigations for GTD

Answer 28

• 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)