Flashcards in Gestational Trophoblastic Disease Deck (53)
What is gestational trophoblastic disease?
A term used to describe a group of pregnancy related tumours
What can gestational trophoblastic disease be divided into?
- Pre-malignant conditions
- Malignant conditions
What form of gestational trophoblastic disease is more common?
What are the types of pre-malignant gestational trophoblastic disease?
- Partial molar pregnancy
- Complete molar pregnancy
What are the types of malignant gestational trophoblastic disease?
- Invasive mole
- Placental trophoblastic site tumour
- Epithelioid trophoblastic tumour
What is the fetus formed from in normal conception, in terms of chromosomes?
23 maternal chromosomes and 23 paternal chromosomes
When does a molar pregnancy arise?
When there is an abnormality in chromosomal number during fertilisation
What is a partial molar pregnancy?
When one ovum with 23 chromosomes is fertilized by 2 sperm, each with 23 chromosomes, producing cells with 69 chromosomes
Can a partial molar pregnancy exist with a viable fetus?
What happens chromosomally in a viable partial molar pregnancy?
Mosaicism where the fetus has normal karyotype and triploidy is confined to the placenta
(Normally the fetus and placenta are triploidy, which isn't viable)
What is a complete molar pregnancy?
Where one ovum without any chromosomes is fertilised by one sperm which duplicates, or less commonly by two different sperm, leading to 46 chromosomes of paternal origin alone
Are molar pregnancies benign or malignant?
Usually benign, but can become malignant
What happens when molar pregnancies become malignant?
They invade into the myometrium and disseminate throughout the body
What are malignant molar pregnancies known as?
What is a choriocarcinoma?
A malignancy of trophoblastic cells of the placenta
What does choriocarcinoma commonly co-exist with?
Where does choriocarcinoma characterically metastasise to?
What is a placental site trophoblastic tumour?
A malignancy of the intermediate trophoblasts
What are the intermediate trophoblasts normally responsible for?
Anchoring the placenta to the uterus
What can placental site trophoblastic tumours occur after?
- Normal pregnancy (more common)
- Molar pregnancy
What is an epithelioid trophoblastic tumour?
A malignancy of the trophoblastic placental cells
What can an epithelioid trophoblastic tumour be difficult to determine from?
What does an epithelioid trophoblastic tumour mimic the cytological features of?
A squamous cell carcinoma
What are the risk factors for gestational trophoblastic disease?
- Maternal age <20 or >35
- Previous gestational trophoblastic disease
- Previous miscarriage
- Use of OCP
How do molar pregnancies most commonly present?
Vaginal bleeding and abdominal pain early in pregnancy
What is found on examination in molar pregnancy?
Uterus can be larger than expected for gestation, and of soft, boggy consistency
What finding can occasionally be present in molar pregnancy?
Molar vesicles shed per vagina
How is the diagnosis of molar pregnancy usually made?
What are the later symptoms may be present if molar pregnancy is missed?