Should grade 3 endometrioid endometrial carcinoma be considered a type 2 cancer-a clinical and pathological evaluation.

Objective: Endometrial cancer is classified into: Type I estrogen-dependent endometrioid adenocarcinoma, with good prognosis and type 2 non-estrogen-dependent cancer with serous or clear cell histology and poor prognosis. Grade 3 endometrioid cancers (G3 EEC), share features of type 1 and type 2 cancer and have not been classified as either. This study compares immunohistochemistry and survival in G3 EEC and type 2 cancers.