What is the treatment for a molar pregnancy?

Treatment of Molar Pregnancy

Primary Treatment: Suction Dilation and Curettage

Suction dilation and curettage (D&C) under ultrasound guidance is the definitive treatment for molar pregnancy in women who wish to preserve fertility. 1, 2 This is the safest method to ensure adequate emptying of uterine contents while avoiding uterine perforation. 1, 2

Surgical Procedure Details

• Perform suction D&C under ultrasound guidance to visualize the procedure and ensure complete evacuation 1
• Have blood products available pre-operatively due to significant hemorrhage risk 2
• Administer uterotonic agents (methylergonovine or prostaglandins) during and after the procedure to reduce bleeding risk 1
• Give Rho(D) immunoglobulin at evacuation to all Rh-negative patients 1

Alternative for Completed Fertility

• Hysterectomy may be considered for patients who no longer desire fertility, as it reduces the risk of developing postmolar gestational trophoblastic neoplasia (GTN) 3

Important Caveat

• Do not perform biopsy of visible lesions in the lower genital tract due to life-threatening hemorrhage risk 4, 2

Post-Evacuation Monitoring Protocol

All women with molar pregnancy require mandatory hCG surveillance to detect postmolar GTN, which develops in 15-20% of complete moles and 1-5% of partial moles. 2

HCG Monitoring Schedule

• Measure hCG every 1-2 weeks until normalization (defined as 3 consecutive normal assays) 4, 1
• After normalization, measure hCG twice at 3-month intervals 4, 1
• For complete moles: continue monthly hCG for 6 months after normalization 2
• For partial moles: one additional normal hCG measurement one month after normalization 2

Contraception Requirement

• Reliable contraception is mandatory during the entire follow-up period to avoid confusion between pregnancy-related hCG elevation and GTN 1

Diagnosis of Postmolar GTN

Postmolar GTN is diagnosed when meeting ANY of the following FIGO criteria: 4, 1

• hCG plateau: 4 consecutive values over 3 weeks
• hCG rise: >10% increase for 3 values over 2 weeks
• hCG persistence: 6 months or more after molar evacuation

Treatment of Postmolar GTN

When GTN is diagnosed, treatment depends on FIGO prognostic scoring:

Low-Risk GTN (FIGO Score 0-6)

Single-agent chemotherapy with methotrexate or actinomycin D is the standard treatment. 4, 1 The ESMO guidelines note that methotrexate with folinic acid (MTX/FA) is preferred in most European centers because it is less toxic than methotrexate alone or single-agent actinomycin D. 4

• Continue chemotherapy for 6 weeks of maintenance after hCG normalization 4
• Methotrexate dosing for trophoblastic disease: 15-30 mg daily for 5 days, repeated 3-5 times with rest periods of one or more weeks between courses 5

High-Risk GTN (FIGO Score ≥7)

Multi-agent chemotherapy is required, with EMA/CO (etoposide, methotrexate, actinomycin D, cyclophosphamide, vincristine) being the most commonly used regimen. 4, 1

• Extend maintenance therapy to 8 weeks for patients with poor prognostic features such as liver with or without brain metastases 4
• For ultrahigh-risk patients: consider induction with low-dose etoposide and cisplatin to reduce early deaths 4

Surgical Options for Persistent GTN

• Repeat D&C or hysterectomy can be considered for persistent postmolar GTN 4
• In one observational study of 544 women: 68% had no further disease or chemotherapy requirements after second curettage 4
• Chemotherapy was more likely needed when histology confirmed persistent trophoblastic disease or urinary hCG exceeded 1,500 IU/L at second evacuation 4

Prophylactic Chemotherapy Considerations

Prophylactic chemotherapy at evacuation is generally NOT recommended as standard practice but may be considered for high-risk patients. 1 A Cochrane review found insufficient evidence for routine prophylactic chemotherapy, though it may reduce GTN risk in women with complete moles at high risk for malignant transformation. 4

High-Risk Factors for Postmolar GTN

Consider prophylactic methotrexate or actinomycin D if: 4, 1

• Age >40 years
• hCG levels >100,000 mIU/mL
• Excessive uterine enlargement
• Theca lutein cysts >6 cm

Staging Workup When GTN is Diagnosed

• Doppler pelvic ultrasound to confirm absence of pregnancy, measure uterine size, and delineate tumor volume and vasculature 4, 1
• Chest X-ray to assess for metastatic disease 4, 1
• If chest X-ray is positive: proceed with brain MRI and CT chest/abdomen/pelvis 1
• Laboratory tests: complete blood count with platelets, liver, renal, and thyroid function tests 4

Long-Term Outcomes and Fertility

• Fertility is not significantly affected: 83% of women become pregnant after MTX/FA or EMA/CO chemotherapy 4
• No obvious increase in congenital malformations in subsequent pregnancies 4
• Risk of recurrent molar pregnancy: 1.0-2.0% in subsequent pregnancies 6
• When pregnancy occurs: confirm normal pregnancy by ultrasound and recheck hCG at 6 and 10 weeks after delivery to ensure no recurrence 4

Critical Contraindication

Endometrial ablation is absolutely contraindicated in patients with a history of molar pregnancy due to the risk of undetected recurrent GTD that could be masked by the ablated endometrium. 2, 7