A 47-year-old woman has a pelvic mass. Laparotomy reveals an 11 cm ovarian mass with cysts containing thick chocolate-brown fluid, and the same ovary harbors a solid area with glandular structures lined by hobnail cells with clear cytoplasm and prominent nucleoli. Which molecular alteration is characteristically associated with this carcinoma?
- A BRCA1 germline mutation with TP53 mutation
- B FOXL2 mutation with granulosa cell differentiation
- C KRAS mutation with low-grade serous morphology
- D ARID1A inactivating mutation with PIK3CA activation ✓
Explanation
Clear cell carcinoma of the ovary frequently arises in an endometriotic cyst, as suggested by the chocolate cyst here. It shows tubulocystic and papillary patterns with hobnail cells and clear cytoplasm, and characteristically harbors ARID1A (SWI/SNF chromatin remodeling) inactivating mutations along with activating PIK3CA mutations. TP53 mutation with BRCA1 linkage defines high-grade serous carcinoma, KRAS mutation typifies borderline and low-grade serous tumors, and FOXL2 mutation is the hallmark of adult granulosa cell tumor. Clear cell carcinoma has a poorer response to platinum chemotherapy.
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.