My Clinical Notes

• Characterised by proliferation of trophoblastic tissue in a progressively malignant potential
• Disease includes
  • Hydatiform mole (complete and incomplete)
  • Invasive mole
  • Choriocarcinoma
• Human chorionic gonadotrophin is secreted in excess

 

Hydatiform mole (complete and incomplete)

• Common, 1 in 1000-2000 pregnancies
• More common in the Far East
• May precede choriocarcinoma
• Charcterised by cystic swelling of the chorionic villi
• Patients present in there 4-5^th month of gestation with vaginal bleeding and a uterus larger than expected for the gestation
• Risk higher for women at the extremes of reproductive age

 

Pathogenesis

• In the complete mole all or most of the villi are oedematous and there is diffuse trophoblastic hyperplasia
  • 90% have a 46XX genotype all derived from the sperm – androgenesis
  • Presumed to result from the fertilisation of an egg which has lot its chromosomes
  • Moles show no fetal parts 

• In partial moles, some villi are oedematous but much are normal and the trophoblastic proliferation is focal
  • Karyotype is triploid (69XXY) or tetraploid (92XXXY)
  • Results from fertilisation of an egg by one of two sperm
  • Fetal parts may be present
  • The partial mole rarely develops into choriocarcinoma

 

• Classic presentation is a uterine cavity filled with a friable mass of translucent, cystic, grape-like structures consisting of hydropic villi

 

Clinical course

• Most patients undergo spontaneous pregnancy loss
• Ultrasound can reveal diffuse villous enlargement – ‘snowstorm’ appearance
• Levels of hCG greater exceed that of a normal pregnancy. This may result in sever vomiting
• Early pre-eclampsia and hyperthyroidism may occur
• Removal may be required through curettage
• 2.5% of complete moles develop into choriocarcinoma
• 10% of complete moles develop into and invasive mole

 

Invasive Mole

 

• This is where the mole penetrates and may even perforate the uterine wall
• There is invasion of the myometrium by oedematous chorionic villi along with proliferation of both cytotrophoblasts and syncytiotrophoblasts
• Villi may embolise to distant sites including the lungs and the brain where they may grow to form true metastases
• Clinical findings are severe vaginal bleeding, irregular uterine enlargement, persistently high levels of hCG
• Responds well to chemotherapy but may require hysterectomy

 

Choriocarcinoma

 

• Malignant neoplasm of trophoblastic cells
• Mostly arise from the uterus but ectopic pregnancies can result in extra-uterine cases
• Rapidly invasive and widely metastasizing
• Responds well to chemotherapy

 

• Uncommon, 1 in 20,000 pregnancies
• As well as resulting from hydatiform moles, they can also occur from previous abortions or normal pregnancies 

Pathology

• Purely epithelial is derivation, no chorionic villi produced
• Grows by proliferation of both cytotrophoblast and syncytiotrophoblast
• Invades myometrium and can penetrate blood vessels and lymphatics
• Metastases to lungs, vagina, brain, bone marrow, kidney and liver
• Because of its rapid growth it is subject to haemorrhage, necrosis and secondary inflammation 

Clinical course

• Doesn’t normally produce a large, bulky uterus
• Presents as irregular spotting of bloody, brown, foul smelling fluid
• Usually by the time it presents, metastases can be detected
• Levels of hCG are elevated above those of hydatiform moles

 

 

Treatment

 

• Evacuation of uterine contents
• Surgery
• Chemotherapy
  • Methotrexate
  • Actinomycin D
  • Etoposide
• Gestational choriocarcinoma is very sensitive to chemotherapy – almost 100% of patients experience remission
• Nongestational choriocarcinoma is less sensitive 

• Recurrence of molar pregnancies occurs in 1 in 60 subsequent pregnancies

This entry was posted on Saturday, September 29th, 2007 at 4:41 pm and is filed under Gynaecology/Obstetrics. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.