Gestational trophoblastic disease

Question 1

What is gestational trophoblastic disease?

Answer 1

Gestational trophoblastic disease (GTD) is a group of conditions in which tumors grow inside a woman’s uterus (womb). The abnormal cells start in the tissue that would normally become the placenta.

Question 2

What are the three main types of gestational trophoblastic disease?

Answer 2

Complete hydatidiform mole

Partial hydatidiform mole

Choriocarcinoma

Question 3

What is complete hydatidiform mole, one of the gestational trophoblastic diseases?

Answer 3

Benign tumour of trophoblastic material. Occurs when an empty egg is fertilized by a single sperm that then duplicates its own DNA, hence the all 46 chromosomes are of paternal origin.

Question 4

What are the features of complete hydatidiform molar pregnancy?

Answer 4

Bleeding in first or early second trimester
Exaggerated symptoms of pregnancy e.g. hyperemesis
Uterus large for weeks of gestation
Very high serum levels of human chorionic gonadotropin (hCG)
Hypertension
Features of hyperthyroidism

Question 5

Why are features of hyperthyroidism seen in complete hydatidiform molar pregnancy?

Answer 5

hCG can mimic thyroid-stimulating hormone (TSH) at the very high levels seen in complete hydatidiform molar pregnancy.

Question 6

What investigations would be performed in someone with suspected complete hydatidiform molar pregnancy?

Answer 6

Serum hCG

Ultrasound

Question 7

What would be seen on ultrasound of someone with complete hydatidiform molar pregnancy?

Answer 7

Molar pregnancy has a characteristic ‘bunches of grapes’ appearance on ultrasound.

Question 8

How do we treat women with complete hydatidiform molar pregnancy?

Answer 8

Urgent referral to specialist centre

Evacuation of the uterus is performed

Effective contraception is recommended to avoid pregnancy in the next 12 months

Question 9

What is partial hydatidiform molar pregnancy?

Answer 9

This is when a normal haploid egg may be fertilized by two sperms, or by one sperm with duplication of the paternal chromosomes. Therefore the DNA is both maternal and paternal in origin. Usually triploid - e.g. 69 XXX or 69 XXY.

Question 10

What are the complications of hydatidiform molar pregnancy?

Answer 10

Choriocarcinoma
Preeclampsia
Thyroid problems
Molar pregnancy that continues or comes back

Question 11

What percentage of complete hydatidiform molar pregnancies go on to develop choriocarcinoma?

Answer 11

2-3%

Question 12

Where do metastases of choriocarcinoma usually go?

Answer 12

Lung
Liver
Brain