Placental site trophoblastic tumor (PSTT) differs from choriocarcinoma in which important clinical and histological feature?

• A PSTT secretes very high levels of beta-hCG proportional to tumor bulk, whereas choriocarcinoma secretes modest hCG
• B PSTT arises from villous cytotrophoblast, whereas choriocarcinoma arises from intermediate trophoblast
• C PSTT is relatively resistant to chemotherapy, preferentially treated by hysterectomy, and secretes mainly hPL (human placental lactogen) with low beta-hCG ✓
• D PSTT is always benign and never metastasizes

Explanation

PSTT arises from intermediate (implantation site) trophoblast, secretes predominantly human placental lactogen (hPL) with disproportionately low beta-hCG relative to tumor bulk, and is relatively chemoresistant. Hysterectomy is the preferred treatment for localized PSTT. Choriocarcinoma arises from villous trophoblast, secretes very high beta-hCG, and is exquisitely chemosensitive. Epithelioid trophoblastic tumor (ETT) is another intermediate trophoblastic tumor.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.