Placental site trophoblastic tumor (PSTT) differs from choriocarcinoma in that PSTT:
- A Has a higher βhCG level relative to tumor bulk
- B Arises from intermediate trophoblast and is relatively resistant to chemotherapy ✓
- C Most commonly follows a complete hydatidiform mole
- D Responds well to EMA-CO as first-line treatment
Correct answer: B. Arises from intermediate trophoblast and is relatively resistant to chemotherapy
Explanation
PSTT arises from intermediate trophoblast (implantation site) rather than villous trophoblast. It secretes predominantly human placental lactogen (hPL) with relatively low βhCG levels despite significant tumor bulk. PSTT is notably chemoresistant compared to choriocarcinoma; hysterectomy is the treatment of choice for localized disease. It most commonly follows a term pregnancy, not a mole.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.