MKI67 and endometrial cancer: An immunohistochemistry study of 77 patients evaluated estrogen (ER) receptor, progesterone (PR) receptor, p53 and Ki-67, reported that tumors with high-grade squamous differentiation (lack of expression of ER and PR; high Ki-67 index and p53 expression) have a worse outcome.[23] This controversy about the prognosis of recurrence in endometrial cancer with squamous differentiation may be related to subgroups of its classification.