Gestational Trophoblastic Disease (Hydatidiform Mole & Choriocarcinoma)

Key Features

Essentials of Diagnosis

• Hydatidiform mole

  • Amenorrhea

  • Irregular uterine bleeding

  • Serum human chorionic gonadotropin (hCG) β-subunit > 40,000 milli-units/mL

  • Passage of grape-like clusters of enlarged edematous villi per vagina

  • Ultrasound of uterus shows characteristic heterogeneous echogenic image and no fetus or placenta

  • Cytogenetic composition is 46,XX (85%) of paternal origin

• Choriocarcinoma: Presence of detectable β-hCG after mole evacuation

General Considerations

• Gestational trophoblastic disease is a spectrum of disorders, including

  • Hydatidiform mole (partial and complete)

  • Invasive mole (local extension into the uterus or vagina)

  • Choriocarcinoma (malignancy often complicated by distant metastases)

  • Placental site trophoblastic tumor

• Complete moles show no evidence of a fetus on ultrasonography; the majority are 46, XX with all chromosomes of paternal origin

• Partial moles generally show evidence of an embryo or gestational sac; are triploid, slower-growing, and less symptomatic; and often present clinically as a missed abortion

Demographics

• Highest rates of gestational trophoblastic neoplasia occur in Asians

• Risk factors include prior spontaneous abortion, a history of mole, and age below 21 or above 35

Clinical Findings

Symptoms and Signs

• Hydatidiform mole

  • Excessive nausea and vomiting may occur

  • Uterine bleeding beginning at 6–16 weeks is usual

  • In some cases, the uterus appears larger than would be expected

  • Bilaterally enlarged cystic ovaries may be palpable

  • Less commonly, preeclampsia-eclampsia may develop during the second trimester

• Choriocarcinoma may be manifested by continued or recurrent bleeding

  • After evacuation of a mole

  • Following delivery, abortion, or ectopic pregnancy

  • An ulcerative vaginal tumor, pelvic mass, or distant metastases may be the presenting manifestation

Differential Diagnosis

• Similarly elevated levels of serum β-hCG subunit are seen in multiple gestation

  • Spontaneous abortion

  • Ectopic pregnancy

  • Prolapsed uterine fibroid

  • Uterine leiomyomas (fibroids), endometrial polyp, or adenomyosis (uterine endometriosis)

  • Ovarian tumor

  • Cervical neoplasm or lesion

Diagnosis

Laboratory Tests

• High serum β-hCG subunit values

  • Can range from high normal to the millions

  • Levels are higher with complete moles than with partial moles

  • Can cause the release of thyroid hormone, and rarely, symptoms of hyperthyroidism will be present

• Serum β-hCG values are more helpful in managing response to treatment than they are for diagnosis

• Hematocrit, creatinine, blood type, liver chemistries, and thyroid function tests

Imaging Studies

• Preoperative diagnosis is made with ultrasonography

• Placental vesicles can be easily seen on transvaginal ultrasound

• Preoperative chest radiograph is required to evaluate for pulmonary metastases of trophoblast

Treatment

Medications

• Chemotherapy is indicated for mole if malignant tissue is discovered at surgery or during follow-up examination ...