Placental site trophoblastic tumor (PSTT) differs from choriocarcinoma in all of the following features EXCEPT:

• A PSTT arises from intermediate trophoblasts rather than cytotrophoblasts and syncytiotrophoblasts
• B PSTT produces relatively low beta-hCG relative to tumor bulk
• C PSTT is relatively insensitive to EMA-CO chemotherapy
• D PSTT has a high cure rate with single-agent methotrexate ✓

Explanation

PSTT arises from implantation-site intermediate trophoblasts and characteristically produces low beta-hCG with high HPL (human placental lactogen). Unlike choriocarcinoma, PSTT is relatively chemotherapy-resistant — EMA-CO has limited efficacy, and the treatment of choice is hysterectomy (for disease confined to the uterus) or EP/EMA for metastatic disease. Single-agent methotrexate is not curative for PSTT.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.