A 45-year-old woman undergoes hysterectomy for a uterine mass. Histology shows a tumor composed of cells resembling endometrial stroma, exhibiting a characteristic 'tongue-like' pattern of infiltration into the myometrium. Which immunohistochemical marker is most likely to be positive in this tumor?

• A WT-1
• B Inhibin
• C S100
• D CD10 ✓

Explanation

Endometrial stromal sarcomas are characterized by a 'tongue-like' infiltrative pattern and are typically positive for CD10. Inhibin is positive in sex cord-stromal tumors (granulosa cell tumor), S100 in neural/melanocytic tumors, and WT-1 in serous ovarian carcinomas.

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.