Gestational Trophoblastic Disease

Introduction

Gestational Trophoblastic Disease (GTD) is the abnormal growth of cells in the uterus that is usually associated with an abnormal placental or pregnancy tissue.   Usually this is diagnosed when a woman suspects or knows she is pregnant.  Typically there is bleeding in these pregnancies or an abnormal ultrasound.  This is referred to as a “Molar Pregnancy” (Hydatidiform mole) and can be a complete or partial mole depending on the nature of the abnormal pregnancy event.  This diagnosis is made formally after a D+C procedure where the tissue is removed from the uterus and examined.

For many women who have a molar pregnancy, it is treated by removal of the tissue from the uterus (D+C).  The doctor will follow the pregnancy hormone levels (HCG) to ensure these levels go to zero.  It is important to follow these levels months for 6 months to ensure they stay at zero.  During this time it is important to use birth control to prevent a new pregnancy because that can make discovery of a recurrence difficult and delay lifesaving treatment.

Gestational Trophoblastic Neoplasia (GTN)
About 10-20% of women who experience a molar pregnancy will have an increase in the HCG levels after the D+C and are then diagnosed with Malignant Gestational Trophoblastic Disease, which is a type of GTD

GTD can also be diagnosed in the absence of a recent pregnancy event or after any type of pregnancy even miscarriages, tubal pregnancy or a normal pregnancy and delivery. 

Choriocarcinoma and placental site trophoblastic tumors are more rare types of GTD.

In all of these cases the blood test HCG is typically elevated and helps the doctor follow the response to treatment.

Incidence:

The incidence of hydatidiform mole ranges from 23 to 1299 cases per 100,000 pregnancies, while malignant GTD is less common.

Signs and Symptoms:

Clinical manifestations of GTD include, in decreasing order of frequency:
Vaginal bleeding
Enlarged uterus
Pelvic pressure or pain
Theca lutein cysts
Anemia
Hyperemesis gravidarum
Hyperthyroidism
Preeclampsia before 20 weeks of gestation
Vaginal passage of hydropic vesicles
Women with GTD who present with these clinical features are often misdiagnosed. Since pregnancy is by far the most common source of human chorionic gonadotropin (HCG), clinicians most often initially suspect a pregnancy complication (threatened or missed abortion, ectopic pregnancy) rather than GTD in women who present with vaginal bleeding, an enlarged uterus, and pelvic discomfort and have a positive pregnancy test.
With that being said most women with GTD are diagnosed early because of the use of blood tests and ultrasound early in pregnancy.

Treatments for Gestational Trophoblastic Neoplasm:

Your treatment choice depends on many factors. The location and the extent of the disease are very important. Other important factors include the type of GTD present, the level of HCG, duration of the disease, sites of metastasis if any, and the extent of prior treatment. In selecting a treatment plan, you and your medical team will also consider your age, general state of health, and personal preferences.
It is important to begin treatment as soon as possible after GTD has been detected. The main methods of treatment are:

  • Surgery (D+C or sometimes a hysterectomy)
  • Chemotherapy

Sometimes the best approach combines 2 or more of these methods. It is important to discuss all of your treatment options, including their goals and possible side effects, with your doctors to help make the decision that best fits your needs. It’s also very important to ask questions if there is anything you’re not sure about.

Source: The information on this page comes directly from articles on the UpToDate medical database.