A 35-year-old woman presents with irregular vaginal bleeding 18 months after a full-term delivery. Serum β-hCG is 45,000 mIU/mL. Chest X-ray shows multiple lung metastases. Brain MRI and liver ultrasound are normal. Histology from an endometrial curettage shows sheets of anaplastic cytotrophoblast and syncytiotrophoblast with extensive hemorrhage and necrosis, and NO villous structures are identified. What is the diagnosis?
- A Invasive mole
- B Placental site trophoblastic tumor
- C Choriocarcinoma ✓
- D Epithelioid trophoblastic tumor
Correct answer: C. Choriocarcinoma
Explanation
Choriocarcinoma is diagnosed by the triad of biphasic trophoblastic proliferation (cytotrophoblast and syncytiotrophoblast), hemorrhage/necrosis, and ABSENCE of villous structures. The 18-month interval after a term pregnancy is classic. Invasive mole retains villous structures. PSTT shows intermediate trophoblast without biphasic pattern. Epithelioid trophoblastic tumor has nodular growth of intermediate trophoblast. Choriocarcinoma can follow any pregnancy type.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.