Histopathological examination of a curetted specimen from a woman with persistent beta-hCG elevation after molar evacuation shows molar chorionic villi infiltrating the myometrium along with proliferating cytotrophoblast and syncytiotrophoblast. Which diagnosis fits these findings?

• A Gestational choriocarcinoma
• B Placental site trophoblastic tumour
• C Placental site nodule
• D Invasive hydatidiform mole ✓

Explanation

The defining histological feature of invasive mole is the presence of molar chorionic villi penetrating into or through the myometrium, sometimes via vascular channels. It occurs in 10 to 15 percent of complete moles and is locally invasive but rarely metastasises. Choriocarcinoma is distinguished precisely by the absence of chorionic villi, showing instead sheets of cytotrophoblast and syncytiotrophoblast with central haemorrhage and necrosis. Placental site trophoblastic tumour consists of intermediate trophoblast secreting human placental lactogen rather than marked hCG.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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