II. Epidemiology: Incidence
- North America and Europe: 1:1000 to 1:1500 pregnancies
- Asia and Latin America: 1:400 to 1:200 pregnancies
- Philippines: 1:250
III. Risk Factors
- Prior Molar Pregnancy
- Extremes of reproductive age
- Age under 20 years
- Age over 45 years
- Twin Gestation
- High Parity
- Malnutrition
IV. Pathophysiology
- Form of Trophoblastic Neoplasia
- Benign proliferation of chorionic villi
- Fetus absent
-
Choriocarcinoma (risk: 10-20%) predisposing factors
- Complete hydatiform mole
- Abnormally proliferative trophoblast
- Pitocin or Hysterectomy for mole evacuation
- Oral Contraceptive use after mole evacuation
V. Types
- Complete Mole
- Total hydatidiform change
- Marked proliferation of trophoblastic cells
- No evidence of fetal vessels
- Karyotype: 46XX (all paternally derived)
- Derived from haploid 23X sperm
- Sperm duplicates Chromosomes without cell division
- Higher risk for malignant change
- Partial Mole
- Associated with non-viable fetus or vessels only
- Moderate trophoblastic proliferation
- Karyotype: Triploid (69XXX or 69XXY)
- Fertilization by more than one sperm
- Malignant change less likely than in complete mole
VI. Symptoms
- Vaginal Bleeding during pregnancy in 3rd-4th month
- Hyperemesis Gravidarum
- Passage of grapelike villi from the Uterus
- Abdominal Pain early in pregnancy
- Pallor or Dyspnea
- Associated with Anemia
- Anxiety and Tremor
- Due to weak Thyroid stimulation by HCG
VII. Signs
- Excessive Uterine enlargement
- Larger than expected for Gestational Age
- Fetus absent
- Fetal Heart Tones absent
- Absent fetal parts
- Ovarian enlargement (10%)
- Related to theca-lutein cysts
- Onset Hypertension early in pregnancy
- Occurs before Pregnancy Induced Hypertension
- Occurs in first or second trimester
VIII. Histology
- Gross Examination
- Whitish grape-like cluster
- Interspersed blood clots
- Microscopic changes of villi
- Trophoblastic proliferation
- Cytotrophoblast (Langerhans Cell) proliferation
- Cuboid cells
- Prominent nuclei
- Syncytiotrophoblast proliferation
- Sheets of cytoplasm proliferate
- Dark oval nuclei
- Cytotrophoblast (Langerhans Cell) proliferation
- Hydropic changes to central stroma
- Cystic spaces form (cisterns)
- Avascular edematous spaces form
- Fetal Vessels absent
- Trophoblastic proliferation
IX. Labs
-
Quantitative bhCG
- Excessively elevated above expected levels
- Level may exceed 1 Million IU
- Directly reflects tumor volume
- Complete Blood Count
- Liver Function Testing
- Thyroid Function Testing
X. Radiology
- Molar Pregnancy screening: Pelvic Ultrasound
- Mass of Vesicles appears like snowstorm
- Differential diagnosis
- Septic Abortion
- Fibroma
- Molar Pregnancy confirmed
- Chest XRay
- Consider CT Head and Abdomen
XI. Complications
- Malignant transformation to Choriocarcinoma in 10-20%
- Locally Invasive Mole: Chorioadenoma destruens (66%)
- Gestational Choriocarcinoma (33%)
- Hyperthyroidism
- Pregnancy Induced Hypertension
XII. Management
- Evacuation of Uterus
- Dilatation and Evacuation
- Dilatation and Curettage
- Avoid Hysterectomy, Hysterotomy, or Pitocin
- Increased risk of metastasis (Relative Risk: 3.0)
- Clamp uterine vessels early if Hysterectomy needed
-
Chemotherapy Indications after D&C
- Quantitative bhCG persistently elevated
- Persistent uterine bleeding
- Evidence of trophoblastic metastasis
- Brain
- Lungs
XIII. Monitoring
- Follow Quantitative bhCG levels until 0
- Serial bHCG for 6 months to 1 year
- Use Contraception during this time
-
Chemotherapy if bHCG rises or does not fall to 0
- Methotrexate usually used
XIV. Prognosis
- Recurrence rate of complete mole: 20%
- May recur as locally invasive or metastatic
- Recurrence rate in future pregnancies: 1-2%
XV. References
- Stenchever (2001) Comprehensive Gynecology, p. 1047-62
- Shapter (2001) Obstet Gynecol Clin North Am 28(4):805 [PubMed]