Gestational trophoblastic neoplasia

Question 1

Gestational trophoblastic neoplasia

Answer 1

very rare
invasive mole - hydatidiform mole/molar pregnancy
choriocarcinoma

Question 2

Etiology of gestational trophoblastic neoplasia

Answer 2

can occur after any pregnancy

usually after non-malignant GTN

Question 3

Natural Hx of gestational trophoblastic neoplasia

Answer 3

hemorrahge
metastasis
preeclampsia, etc

Question 4

Spread of gestational trophoblastic neoplasia

Answer 4

via blood
lungs 80%
pelvis 30%
vagina 20%
brain/liver 10%
bowel, kidney, spleen

Question 5

SSx of gestational trophoblastic neoplasia

Answer 5

large for date pregnancy
bleeding
nausea
no fetal HR
Preeclampsia: 27% historically, now 1-2%
Theca lutein cysts
Hyperthyroidism: chorionic gonadotropin bears structural homology to pit thyrotropin 1

Question 6

Dx of gestational trophoblastic neoplasia

Answer 6

US
very high betahCG
metastatic signs: blood test for kidney, liver, bone, anemia, etc
Imaging: lungs, head, abdomen, pelvis

Question 7

Staging of gestational trophoblastic neoplasia

Answer 7

beta hCG

imaging

Question 8

Tx of gestational trophoblastic neoplasia

Answer 8

D&C

possible chemotherapy for rising betahCG, invasive disease

Question 9

Followup of gestational trophoblastic neoplasia

Answer 9

monthly betahCG
contraception 1 year
early ultrasound and betahCG in next pregnancy

Question 10

Prognosis of gestational trophoblastic neoplasia (malignant)

Answer 10

very good: 95% 5 year
fertility unchanged

High risk prognosis: 5 Fs
antecedent Full term pregnancy
Far away mets
bhCG> 40,000
Failed low risk chemo
>4 mo since pregnancy

Question 11

Hydatidiform mole

Answer 11

Empty ovum fertilized by a haploid sperm then 2x

• -> ovum nucleus deactivated/absent
• -> entirely paternal origin in complete mole
• trophoblast proliferates only

Pregnancy with no embryo but cystic degeneration of chorionic villi

Question 12

Incidence of GTD

Answer 12

Hydatidiform mole 1:1000
Invasive 1:10000
Placental site trophoblastic tumour: 1:20000
Choriocarcinoma: 1:40000

Question 13

Normal placenta biochemical markers

Answer 13

Syncytiotrophoblast - hCG, hPL
Intermediate trophoblast –> hPL
Cytotrophoblast - none

Question 14

Risk factors for GTD/molar pregnancy

Answer 14

Extremes of maternal age (40)
Previous molar pregnancy - 1-2%
?Dietary ?geographical factors

Question 15

Complete mole

Answer 15

diffuse hydatidiform swelling
difuse trophoblastic hyperplasia
No fetal tissue
Karyotype: 2 paternal haploid - 46XX, XY

Question 16

Partial mole

Answer 16

Focal hydatidiform swelling
focal trophoblastic hyperplasia
fetal tissue present
Karyotype: 2 paternal + 1 maternal haploid, 69 XXY, XYY

Question 17

Investigations of GTD

Answer 17

Diagnostic imaging: US classic snowstorm pattern
Lab: 
CBC
bhCG - high
thyroid
liver function tests (mets)
renal function (prior to chemo)

Question 18

Management of GTD

Answer 18

CXR - metastatic workup; spreads to lungs first
Dilatation/suction - risk for massive hemorrhage so need to evacuate ASAP
betahCG weekly until normal x3 and then monthly for a year
6-12 mo
Average time to normalcy 9-11 wks
Contraception 6-12 mo
- Need to follow up betahCG; CANNOT get pregnant!!

Question 19

Danger of GTD

Answer 19

Invasive mole: 15-20% of complete moles; 2-4% of partial moles
Choriocarcinoma: extremely malignant form
Placental site trophoblastic tumour: rare

Question 20

Symptoms/signs of malignant GTD

Answer 20

elevated betahCG but not pregnant
vaginal bleeding
metastatic disease - cerebral, abdominal, pulmonary bleeding
consider GTD in differential in reproductive age woman with systemic disease

Question 21

Management of low risk malignant GTD

Answer 21

Single Agent Chemo - methotrexate, actinomycin D
Combination Chemo: methotrexate + actinomycin D
90% remission

Question 22

Management of high risk GTD

Answer 22

Combination chemo

• MAC
• VPB
• EMA-CO