Malignant Hydatidiform Mole

When vesicular molar tissue extends beyond the uterine cavity, invades deep myometrium or metastasizes elsewhere, it is called malignant hydatidiform mole. The chance of a hydatidiform mole malignant-transforming into malignant mole or choriocarcinoma is 5%-20%; most occur within 6 months after mole evacuation, but some malignant-change before the mole is expelled. Although malignant mole has malignant-tumor features, treatment outcome and prognosis are better than choriocarcinoma. The main symptom of malignant mole is irregular vaginal bleeding within months after mole expulsion, variable amount; uterus slightly enlarged and soft. If uterine perforation occurs, there is abdominal pain, internal bleeding, even shock. Lung metastasis may cause hemoptysis; brain metastasis causes intracranial bleeding symptoms, even immediate death; intestinal metastasis may cause GI bleeding; vulvar/vaginal/cervical metastasis shows local bluish nodules that may rupture causing massive bleeding.

Common Symptoms

Uterine perforation; abdominal pain; shock; internal bleeding

Causes and Pathogenesis

The true cause of malignant mole is unclear; possible factors: The true etiology is unknown. Case-control studies find malignant mole related to nutritional status, socioeconomics and age. Age is a significant factor: women over 40 have 10-fold higher mole incidence than young women; age under 20 is also a high-risk factor for complete mole; women in these two age groups are prone to fertilization defects. Partial mole is unrelated to maternal age. Cytogenetic combined with pathologic studies prove the two types of malignant mole have distinct genetics. The chromosomal genome of malignant mole is paternal: the ovum develops after fertilization with the sperm pronucleus in the absence or inactivation of the ovum pronucleus.

Treatment

Drug therapy, supportive therapy

Preventive Measures

Professional guidance: Since hydatidiform mole is a pregnancy-related disease, family planning, contraception and reduced pregnancy frequency can prevent it; women over 40 should avoid further pregnancy, because advanced pregnancy not only raises mole incidence but also promotes malignant change. After a mole, watch for postoperative malignant change. Close HCG monitoring after dilation and curettage is the main measure to detect malignant change. If HCG remains above normal 12 weeks after curettage, or drops to normal then rapidly rises, after excluding residual mole and re-pregnancy, the patient is in early malignant-mole stage and should receive timely chemotherapy.

Department to Visit

It is recommended to visit the Gynecology department; an appointment can be booked on this platform before the visit.

Warm reminder: The above information is for health science reference only and cannot replace professional medical diagnosis. If you have related symptoms, please seek medical attention at a regular hospital promptly.