A woman with a history of BRCA1 germline mutation undergoes prophylactic bilateral salpingo-oophorectomy. The pathologist finds a microscopic focus of high-grade serous carcinoma in the fimbriated end of the fallopian tube. This finding supports which current concept about ovarian high-grade serous carcinoma?

• A Most arise from ovarian surface epithelium via TP53 mutation
• B Most arise from endometriosis via ARID1A mutation
• C Most arise from fallopian tube secretory cells via serous tubal intraepithelial carcinoma (STIC) ✓
• D Most arise from cortical inclusion cysts via KRAS mutation

Explanation

Current evidence strongly supports that most high-grade serous carcinomas (HGSC), particularly BRCA-associated ones, originate from fallopian tube secretory epithelial cells as serous tubal intraepithelial carcinoma (STIC), which then implants on the ovary. TP53 mutation is universal in HGSC but not the initiating event from ovarian surface. ARID1A mutation characterizes clear cell and endometrioid carcinomas arising from endometriosis. KRAS mutation is a feature of low-grade serous carcinoma.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.