A 55-year-old postmenopausal woman presents with vaginal bleeding. Endometrial biopsy shows glands with back-to-back architecture, cribriform pattern, and minimal intervening stroma (>50% replacement). This is BEST classified as:
- A Complex hyperplasia without atypia
- B Endometrial intraepithelial neoplasia (EIN) / atypical hyperplasia
- C Endometrioid adenocarcinoma grade 1 ✓
- D Secretory endometrium
Correct answer: C. Endometrioid adenocarcinoma grade 1
Explanation
When glands replace >50% of the endometrial tissue with a back-to-back/cribriform architecture and minimal intervening stroma, the diagnosis is endometrioid adenocarcinoma (FIGO grade 1 if <5% solid non-squamous, non-morular component). EIN/atypical hyperplasia is a precursor with less than 50% gland area. FIGO grading of endometrial carcinoma is architectural for grades 1 and 2, with nuclear grade modifying the score.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.