Gestational Trophoblastic Diseases

(GTP; Hydatidiform Mole; Molar Pregnancy)

A disorder that includes hydatidiform mole, invasive mole (choriadenoma destruens), and choriocarcinoma. Hydatidiform mole, the most common, is a tumor of the placenta that is usually benign. It develops from placental tissue during an early pregnancy in which the embryo fails to develop normally. The tumor consists of many small vesicles (sacs) and resembles a large cluster of grapes. Although the condition is fairly rare in the USA, it is common in the Orient and other parts of the world. Other types of GTD are more rare. Invasive mole is a hydatidiform mole that spreads to adjacent structures; choriocarcinoma is a malignant tumor preceded by hydatidiform mole (50% of cases), abortion or term pregnancy (each about 25% of cases).

FREQUENT SIGNS AND SYMPTOMS

  • In early pregnancy, there may be no unusual symptoms.
  • Vaginal bleeding.
  • Morning sickness that is frequently excessive.
  • Passage of vesicle (small sac).
  • Abnormally large or small uterus.

CAUSES

Exact cause is unknown. Genetic factors may be involved.

RISK INCREASES WITH

  • Oriental race.
  • Mother over age 40 or under age 20.
  • Diet lacking in protein, folic acid, and possibly, carotene.
  • History of previous hydatidiform mole or other gestational trophoblastic disease (GTD).

PREVENTIVE MEASURES

No specific preventive measures.

EXPECTED OUTCOME

  • With early diagnosis and treatment of an uncomplicated hydatidiform, the outlook is excellent.
  • Feelings of loss and grief for the terminated pregnancy are common. Feelings of guilt may also be present.
  • Reproductive function is generally not affected. A normal subsequent pregnancy is usual, and complications are similar to those in the general population.

POSSIBLE COMPLICATIONS

  • Excessive bleeding and/or pulmonary problems following the uterine evacuation procedure more likely to occur with an extra large uterus.
  • There is a small risk that a malignant tumor may later develop (choriocarcinoma). Follow-up testing is usually necessary for a year to monitor for this possibility. If a tumor does occur, treatment with chemotherapy (anti-cancer drugs) is uniformly successful.
  • The risk of having a recurrent hydatidiform mole with a future pregnancy is slightly increased.

MANAGEMENT
GENERAL MEASURES

  • Diagnostic tests may include ultrasound to assess uterine contents laboratory studies of blood and/or urine levels of beta-human chorionic gonadotropin (B-hCG, a hormone produced by the placenta); x-ray and amniocentesis.
  • Treatment normally involves suction curettage to evacuate the contents of the uterus. Blood loss is usually moderate and transfusion is rarely necessary.
  • Hysterectomy is a treatment option for women not desirous of future pregnancy or for older women (who might be more likely to develop a malignancy).
  • Regardless of method of treatment, follow-up care is essential to monitor blood and urine levels for the hormone B-hCG that can indicate a malignancy. These tests will be done weekly at first, then monthly for at least a year.
  • A new pregnancy must be delayed for a minimum of 1 year, possibly longer, if the blood and urine tests indicate the hormone levels are still not within normal range. Effective contraceptive methods should be implemented and maintained throughout this time period.
  • Psychological and emotional support are important following diagnosis, during treatment and the follow-up time period of the disorder.