What Is a Hydatidiform Mole?

Hydatidiform mole refers to the proliferation of placental villous trophoblasts after pregnancy. The interstitial is highly edema, forming vesicles of different sizes. The vesicles are connected in a string, shaped like grapes, also known as vesicular placenta (HM). The hydatidiform mole is divided into two types: Complete hydatidiform moles are involved, the entire uterine cavity is filled with blisters, diffuse trophoblasts are proliferated, and no fetal and embryonic tissues are visible; partial hydatidiform moles , swelling and degeneration of some placental villi, and local trophoblasts Hyperplasia, embryos and fetal tissues are visible, but the fetus is more dead, sometimes live babies or teratos that are younger than the gestational age, and very few full-term babies are born.

Basic Information

nickname: Blisters
English name: hydatidiform mole
English alias: vesicular mole

Visiting department: Obstetrics and Gynecology
Multiple groups: Women under 20 and over 40
Common causes: Insufficient estrogen, pregnancy egg defect, inactivation of tumor suppressor gene mutations
Common symptoms: Irregular vaginal bleeding, drainage of vesicular tissue, abdominal pain after menopause

Causes of hydatidiform mole

Nutrition factor

Hydatidiform mole is more common in rice-eating countries, so it is considered to be related to nutrition. Studies have found that the folate activity in serum of patients with gestational trophoblastic tumor (GTT) is very low, and the lack of folate during embryonic blood vessel formation will affect thymidine synthesis and lead to embryo Death and lack of blood vessels in the placental villi; low consumption of carotene in the diet increases the risk of hydatidiform moles; hydatidiform moles increase in areas with vitamin A deficiency; and the content of trace elements Zn and Se in hydatidiform moles decreases.

2. Infectious factors

Many authors believe that hydatidiform moles are related to viral infections, but no real evidence has been found so far.

3. Endocrine disorders

The occurrence of hydatidiform mole is considered to be related to the insufficiency or decline of ovarian function, so it is more common in women under 20 and over 40 years old. Animal experiments have proven that removing the ovaries in early pregnancy can cause vesicular-like changes in the placenta, so it is believed that insufficient estrogen may be the cause of hydatidiform mole.

4. Pregnant egg defect

May be related to the abnormal development of the egg itself.

5. Race factors

Differences in the incidence of hydatidiform moles between the races have been noticed. It has been reported that the incidence of hydatidiform mole in African American women is only half that of other women. In Singapore, the incidence of hydatidiform moles of Eurasian race is twice as high as that of Chinese, Indian and Malaysian.

6. Over-expression of proto-oncogenes and mutation inactivation of tumor suppressor genes

Proto-oncogenes and tumor suppressor genes are genes that control cell growth and differentiation. Activation and overexpression of proto-oncogenes and mutation and inactivation of tumor suppressor genes are related to tumorigenesis.

Hydatidiform mole clinical manifestations

Vaginal bleeding after menopause

Most patients experience irregular vaginal bleeding 2 to 4 months after menopause, with a small initial volume, which is easily misdiagnosed as threatened abortion. Gradually increased in the future, and often repeated a large amount of bleeding, sometimes blister-like tissue can be naturally discharged, which can lead to shock or even death.

Abdominal pain

When the hydatidiform mole grows rapidly and the uterus expands rapidly, it can cause lower abdominal pain. When the hydatidiform mole is excreted, the factor uterus contracts and there is paroxysmal pain in the lower abdomen.

(1) The uterus is abnormally enlarged and softened. Due to villous edema and hemorrhage in the uterine cavity, most hydatidiform moles have a uterus larger than the normal pregnancy uterus in the corresponding month, and the texture is soft. The size of the uterus in one third of the patients matched the menopause month. Less than a few menstrual months, may be due to degeneration of blisters and stop development.

(2) Signs of pregnancy vomiting and pregnancy-induced hypertension Because proliferating trophoblasts produce a large amount of HCG, vomiting is often heavier than normal pregnancy. Because of the rapid growth of the uterus in hydatidiform mole patients, the tension in the uterus is high, so hypertension during pregnancy can occur during early pregnancy, and even acute heart failure or eclampsia occurs.

(3) Ovarian flavin cysts Due to the large amount of HCG stimulation in hydatidiform mole patients, bilateral or unilateral ovaries often show multiple cysts. Generally does not produce symptoms, occasionally acute torsion caused by acute abdominal pain. After the hydatidiform mole is cleared, the flavin cyst can resolve on its own. Flavin cysts can store a large amount of HCG, so patients with hydatidiform cysts after hydatidiform mole excretion, blood and urine HCG disappear slowly than ordinary patients.

(4) Hyperthyroidism A small number of hydatidiform patients have mild hyperthyroidism and plasma thyroxine concentrations have risen, but only about 2% of obvious signs of hyperthyroidism appear, and the symptoms quickly disappear after the hydatidiform mole is cleared.

Hydatidiform mole examination

1.HCG determination

Hydatidiform mole produces a large amount of HCG due to trophoblast proliferation, and the HCG concentration in the serum is much higher than the corresponding month value in normal pregnancy. Therefore, this difference can be used as an auxiliary diagnosis of hydatidiform mole. Because the peak of HCG secretion during normal pregnancy is on the 60th to 70th day, it may be the same as the incidence of hydatidiform mole, which makes diagnosis difficult. If continuous HCG or B-ultrasound can be performed at the same time, the identification can be made.

2. Flow Cytometry (FCM)

Complete hydatidiform karyotype is diploid, and partial hydatidiform mole is triploid.

3. Ultrasound

In normal pregnancy, the gestational sac can be displayed at 4 to 5 weeks of pregnancy. Cardiac pulsation can be seen at 6 to 7 weeks of pregnancy. The fetal heart can be detected as early as 6 weeks of pregnancy and can be heard after 12 weeks of pregnancy. The hydatidiform mole appears as a thick spot or falling snow in the hydatidiform mole, no pregnancy sac is visible, and there is no fetal structure or fetal heart beat sign. Only murmur of uterine blood flow can be heard, and fetal heart cannot be heard.

Hydatidiform mole diagnosis

According to irregular vaginal bleeding after menopause, the uterus is abnormally enlarged and softened, and the fetal body at 5 months of pregnancy cannot be found in the fetal body, the fetal heart cannot be heard, and no fetal movement is detected. A hydatidiform mole should be suspected. Pregnancy hyperemesis, preeclampsia before 28 weeks of pregnancy, and bilateral accessory cysts support diagnosis. If blisters are seen in the vaginal discharge, the diagnosis of hydatidiform mole can basically be determined.

Hydatidiform mole differential diagnosis

Abortion

Abortion has symptoms of vaginal bleeding after menopause. Many cases are misdiagnosed as threatened abortion, but hydatidiform uterus is usually larger than the pregnant uterus during the same period. HCG levels are still high when the pregnancy is over 12 weeks. B-ultrasound can identify both.

2. Twin pregnancy

The uterus is larger than the single pregnancy during the same pregnancy, and the HCG level is slightly higher, which is easy to be confused with hydatidiform mole, but the twin pregnancy has no vaginal bleeding, and ultrasound imaging can confirm the diagnosis.

3. Too much amniotic fluid

It can make the uterus enlarge rapidly. Although it occurs mostly in the third trimester, it must be identified with hydatidiform mole in the second trimester. When there is too much amniotic fluid, there is no vaginal bleeding, the HCG level is low, and the B-ultrasound can confirm the diagnosis.

4. Uterine fibroids with pregnancy

The uterus is also larger than the menopause period. A careful pelvic examination can reveal fibroid protrusions or increased asymmetry of the uterus, and the HCG titer is not high. In addition to the fetal heart rate, the B-mode examination can show substantial parts in fashion.

Hydatidiform mole treatment

Once the diagnosis of hydatidiform mole is confirmed, it should be cleared immediately. When removing hydatidiform moles, care should be taken to prevent excessive bleeding, uterine perforation and infection, and to minimize the chance of future malignant changes.

1. Clear the contents of the uterine cavity

Hydatidiform mole has a large and soft uterus and is prone to perforation of the uterus. The advantages of suction aspiration are fast operation and less bleeding. When suctioning the palace, it is advisable to lower the negative pressure and select a large straw as much as possible to prevent uterine perforation and blockage of hydatidiform mole to affect operation. If there is no suction palace condition, curettage is still feasible.

2. Preventive chemotherapy

Preventive chemotherapy should be given to high-risk patients. The high-risk factors are: age> 40 years; abnormally increased HCG value before hydatidiform mole excretion; trophoblast hyperplasia is obvious or atypical hyperplasia; after hydatidiform mole removal, HCG does not decrease progressively, but after a certain level That is, it will not continue to decline or will always be at a high value; those who have suspicious metastases; those who are unconditionally followed up. Preventive chemotherapy usually uses only one drug, but the amount of chemotherapy drug should be the same as that used to treat trophoblastic tumors. The dose should not be reduced. Chemotherapy should be started 3 days before the palace cleaning as much as possible, using 1 or 2 courses.

3. Hysterectomy

Over 40 years of age, no fertility requirements, malignant tendency, small grapes, abnormally high HCG titer, surgery to remove the uterus.

4. Management of flavin cysts

After the hydatidiform mole is cleared, the flavin cysts can resolve on their own, and generally do not need to be treated. If a torsion occurs, they can be naturally reset after ultrasound and laparoscopic puncture and aspiration. If the reversal time is long, blood circulation disorders and ovarian necrosis occur, surgical treatment is needed.

5. Management of hydatidiform mole with severe PIH

If hydatidiform mole is combined with severe pregnancy-induced hypertension and blood pressure reaches 160 / 110mmHg, especially when there is heart failure or eclampsia, it should be treated symptomatically to control heart failure, sedation, antihypertensive, diuretic, and clear the palace after the condition is stable. But it should not wait too much, because hydatidiform mole is not cleared, and pregnancy-induced hypertension is difficult to control.

Hydatidiform mole prognosis

Under normal circumstances, after the hydatidiform mole is empty, the serum hCG decreases steadily, and the average time for the first drop to normal is 9 weeks, and the longest is no more than 14 weeks. If hCG persists after hydatidiform mole emptying, pregnancy trophoblastic tumors should be considered. High-risk hydatidiform moles should be considered when the following high-risk factors appear: hCG> 100000U / L; the uterus is significantly larger than the corresponding gestational week; ovarian luteinized cysts> 6 cm in diameter or bilateral luteinized cysts; age 40 years; small grapes; repeated hydatidiform moles History; pregnancy complications: hyperemesis gravidarum, hyperthyroidism, etc.

Recurrence tendency: After one hydatidiform mole, the risk of recurring hydatidiform mole is less than 1/50; after two hydatidiform moles, the risk of hydatidiform mole is 1/6; after three hydatidiform moles, the risk of hydatidiform mole is 1/2. .

Hydatidiform mole prevention

Follow-up consultation is extremely important. Malignant changes can be detected early and chemotherapy can be used in time. Hydatidiform mole should be checked for hematuria HCG once a week after Qing Palace. Once it is reduced to normal, once every half month, to 3 months later, once a month for 1 year, and then once every six months for 2 years. Follow-up visits should pay special attention to changes in hematuria HCG, and at the same time gynecological examination should be performed to understand the situation of uterine restoration, pay attention to patients with abnormal vaginal bleeding, hemoptysis and other metastatic symptoms. Parallel pelvic B-ultrasound, chest X-ray, or CT were performed. Hydatidiform moles mostly occur within one year, but there are also those who have more than 10 years, so the follow-up period should be maintained for more than 10-15 years.