Molar Pregnancy

Molar Pregnancy

Molar Pregnancy

• Also known as Gestational Trophoblastic Disease(GTD)
• Molar pregnancy is a form of abnormal pregnancy
• Results from a defective fertilization process

Characterized by vesicular swelling of placental tissue hence appearing like vesicles.

GENERAL CONSIDERATION

GTD is a complex condition that results from process of reproduction It is a neoplastic process that span from a locally generative process to a highly malignant neoplasm.

• It includes a tumor spectrum of :-
• Hydatidiform mole
• Invasive mole

Choriocarcinoma

A unique tumor in that:First and only disseminated solid tumor that has proved to be highly sensitive to chemotherapy.

Molar pregnancy-Types

• Hydatidiform mole (benign)
• Complete Hydatidiform mole

Partial Hydatidiform mole

Major difference between the two types is that partial moles contain fetal/embryonic tissue and complete moles do not.

Malignant Mole(Choriocarcinoma) Transformation of benign mole into malignant mole- invasive mole

Complete Mole

Results from fertilization of a blighted (empty) ovum by a paternal chromosome, which then duplicates to reach the haploid compliment of 46 chromosomes Lack fetal tissues

• Uterus is filled with generalized swelling of trophoblastic (placental) tissue.
• Homozygous

Empty Ovum

• 23 X

46 XX

Partial mole

• Fertilization of a normal 23X ovum by two independent sperms resulting in 69 chromosomes.
• Presence of both fetal tissues and abnormal placental tissues
• 23X

69XXX

Natural history of hydatidiform mole

• 80% of molar gestations will resolve completely after evacuation.
• The remaining 20% will develop persistent trophoblastic disease being:-
• 15% invasive mole
• 5% choriocarcinoma.

After an initial molar evacuation the risk for a second mole is increased to between 4 to 5 times.

After a single spontaneous resolution following fertility and reproductive function returns to within normal limits.

Signs and Symptoms

• Amenorrhea – b’se it is a pregnancy
• Vaginal bleeding ( 90%) usually after 12 wks of amenorrhea
• Passage of vesicles (grape like masses) per vagina

Hyper emesis gravidarum ( severe nausea &vomiting) – exaggerated early pregnancy symptoms Size of the uterus is inconsistent with gestational age( with no fetal heart beat and fetal movement) usually soft Preeclampsia in the 1sttrimester or other pregnancy induced hypertension.

Signs and Symptoms

• Ovarian (Theca lutein) cysts
• Features of hyperthyroidism(Anxiety, restlessness, excessive sweating) etc.

Clinically, not possible to determine fetal parts, Fetal heart rate Larger uterus/FH than expected GA. Is due to expansion of endometrial cavity by placental tissues and retained blood. However in some cases, FH may be smaller than expected GA

Signs and Symptoms

In approximately ½ of patients diagnosis is at the time of spontaneous passage of the characteristic vesicles.

Abortion usually occurs at about 16-18 weeks compared to 10-12 weeks in other usual spontaneous abortions.

Diagnosis

• Suspicion: clinical history and physical exam
• Quantitative beta-HCG
• Ultrasound is the standard for identifying both complete and partial molar pregnancies.

The classic image is of grape appearance

Physical exam demonstrates:-

Sometimes features of hyperthyroidism

Diagnosis

• Ultrasound is a reliable and sensitive technique.

LAB: Elevated hCG in urine and serum In most instances hCG regress and disappear within 14 weeks of evacuation of molar pregnancy.

If hCG persists or stagnates or rises it must be concluded that viable tumor cells still persists and this leads to persistent GTD.

Ultrasound is a reliable and sensitive technique.

Elevated hCG in urine and serum

In most instances hCG regress and disappear within 14 weeks of evacuation of molar pregnancy.

If hCG persists or stagnates or rises it must be concluded that viable tumor cells still persists and this leads to persistent GTD.

Molar pregnancy

• Complete mole
• No gestational sac
• Uterus filled with hypoechoic and hyperchoic contents.
• Numerous small cystlike spaces within the mass
• Check HCG-level (very high usually)

Extreme nausea and projectile vomiting

Molar Pregnancy: US Findings

• Complete Mole: Heterogeneous, irregular endometrial mass
• echogenicity variable
• “cluster of grapes” relatively late appearance
• + Myometrial invasion
• Partial Mole: Fetus w/ a “thick placenta”

Theca lutein cysts

Molar pregnancy (Complete mole)

Complete Mole

Molar Pregnancy

A 44 year old woman presents with a 2 month history of amenorrhea. She now complains of severe vaginal bleeding and abdominal pain. She has a beta HCG level of approximately 200,000 units.

Hydatidiform mole: Partial Mole

In a ‘partial mole’, the mass may contain both these abnormal cells and often a fetus that has severe defects.

In this case the fetus will be consumed( destroyed) by the growing abnormal mass very quickly.

Partial Mole

Complete Mole

Partial Mole

Theca lutein cysts

• Bilateral, involving both ovaries
• Thick walled

Complex cystic masses: arranged in spoke-wheel pattern

Theca Lutein cysts

Malignant Mole

Malignant Mole most commonly develops after molar pregnancy, but may occur after any gestational experience: abortion, ectopic, preterm or term pregnancy Invades the myometrium or adjacent structures it may totally penetrate the myometrium leading to uterine rupture and haemoperitoreum(Blood in the peritoneum).

Follow-up following molar pregnancy

• Important because of the possibility of persistent molar
• Following molar evacuation, perform serial hCG determination as follows:-

• Physical work-up is equally important to rule-out metastatic disease:-

Follow-up following molar pregnancy

• Place the patient on oral conceptive pills during follow-up.
• NOTE: Avoid IUCD – Risk of perforation
• Avoid Depo- provera -Irregular bleeding
• At completion of follow-up pregnancy may be undertaken.
• Complications of molar pregnancy
• Haemorrhage.
• Sepsis
• Perforation during Evacuation
• Persistent GTD

Thyroid storm