Hydatidiform mole

Question 1

Definition

Answer 1

Type of tumour that grows like a pregnancy inside the uterus. This is called a molar pregnancy.

Question 2

Types of molar pregnancy

Answer 2

Complete mole: two sperm cells fertilise an ovum that contains no genetic material (empty ovum). These sperm then combine genetic material and the cells start to divide and grow into a tumour. No fetal material will form
Partial mole: two sperm cells fertilise a normal ovum (containing genetic material) at the same time. The new cell has three sets of chromosomes (haploid cell). The cell divides and multiplies into a tumour, some fetal material may form

Question 3

Signs

Answer 3

Molar pregnancy behaves like a normal pregnancy. Periods will stop and the hormonal changes of pregnancy will occur. Things that can indicate a molar pregnancy:
- More severe morning sickness
- Vaginal bleeding
- Increased enlargement of the uterus
- Abnormally high hCG
- Thyrotoxicosis (hCG can mimic TSH and stimulate the thyroid to produce excess T3 and T4)

Question 4

Diagnosis

Answer 4

FIRST LINE: USS of the pelvis shows a characteristic “snowstorm appearance” of the pregnancy.
GOLD STANDARD: histology of the mole after evacuation.

Question 5

Treatment

Answer 5

• Evacuation of the uterus to remove the mole then sent for histological examination.
• Px should be referred to the gestational trophoblastic disease centre for management and follow up. The hCG levels are monitored until they return to normal.

Question 6

Complications

Answer 6

Occasionally the mole can metastasise, and the patient may require systemic chemotherapy.