Section of endomyometrium, in a 64 year old woman who underwent total hysterectomy for uterovaginal prolapse.
The endomyometrium show regular, round and focally crowded glands, haphazardly infiltrating the myometrium with no inflammatory or desmoplastic response. The glands contain eosinophilic secretions and simulate mesonephric remnants or mesonephric hyperplasia. The immunohistochemical markers for mesonephric differentiation ( GATA3, calretinin and CD10) are negative. Additionally mCEA is also negative. The glands are positive for PAX8 and ER. This pattern is most consistent with endometrioid adenocarcinoma with an adenoma malignum pattern of myometrial invasion.
Case submitted by Dr. Sonali Lanjewar, Albert Einstein Medical Center