OG34.3 | Gestational Trophoblastic Disease — Summary & Reflection

KEY TAKEAWAYS

Gestational trophoblastic disease spans a spectrum from hydatidiform mole to choriocarcinoma, all unified by trophoblastic origin and responsiveness to β-hCG monitoring. Key learning points: (1) Complete mole = diploid, androgenetic, no fetal tissue, 15–20% malignant transformation risk; partial mole = triploid, biparental, fetal tissue present, <5% risk. (2) Post-molar GTN is diagnosed by β-hCG plateau (≥3 weeks, <10% change), rise (≥10% over 2 consecutive weeks), or persistent elevation beyond 8 weeks — not by histology. (3) FIGO staging (I–IV, anatomical) combined with WHO/FIGO prognostic score (0–13) determines treatment: ≤6 = low-risk (methotrexate) vs ≥7 = high-risk (EMA-CO). (4) Low-risk GTN: methotrexate ± folinic acid rescue → cure rate >95%; switch to actinomycin-D if resistant. (5) High-risk GTN: EMA-CO → cure rate >85% even in stage IV; salvage EMA-EP for EMA-CO failure. (6) PSTT/ETT: relatively chemoresistant; hysterectomy preferred. (7) Subsequent pregnancy: normal outcomes; defer 12 months after completing surveillance. (8) Cross-reference: OG9.5 covers the acute presentation and initial evacuation of molar pregnancy — this SDL provides the oncological staging and management framework.

REFLECT

Consider the unique aspects of GTD management that distinguish it from virtually all other cancers: a diagnosis made on blood tests alone (no biopsy needed), a cure rate exceeding 90% even in metastatic disease, and complete preservation of fertility in most cases. Reflect on why this disease became the prototype for chemotherapy cure in oncology. Now think about the clinical system requirements that make these outcomes possible: the mandatory β-hCG surveillance protocol, the GTD treatment registries, the specialist centre model, and the contraception requirement during monitoring. If you were counselling a 30-year-old woman who has just been told she has a complete mole and needs six months of β-hCG follow-up with strict contraception, what are the three most important points you would communicate to give her an accurate and reassuring understanding of her situation?