Yano M, et al. - In this retrospective study, researchers evaluated the utility of TP53 abnormalities in endometrial endometrioid carcinoma in supplementing the current grading system and improving its ability to predict clinical outcomes. They analyzed immunohistochemical expression of TP53 using tissue microarrays from the surgically resected specimens of 475 patients with endometrial endometrioid carcinoma. TP53-normal expression comprised weak or moderate expression while TP53-aberrant expression was defined as the absent or strongly positive expression. They diagnosed the endometrial endometrioid carcinomas originally as grade 1 (G1: 69%), grade 2 (G2: 18%), and grade 3 (G3: 13%). In univariate analyses, TP53-aberrant expression was noted to be associated with poor survival in G1 and G2 cases, but not G3 cases. Furthermore, TP53-aberrant expression was observed to be correlated with age (<60 years vs. ≥60 years) in G1 cases, but not in G2 or G3 cases. These findings suggest that improvement in the traditional histological grading system for endometrial endometrioid carcinoma in predicting the patient’s prognosis could be achieved by combining it with immunohistochemical TP53 expression.