Correlation between histological grading and growth-related factors in human endometrial adenocarcinomas

In order to clarify biological significance of histological grading of malignant tumors, several "growth-related factors" were examined and compared in human endometrial adenocarcinomas with different histological grades. Growth fraction (estimated by Ki-67 immunostain) and cytoplasmic bcl-2 and nuclear p53 overexpression were estimated immunohistochemically in 40 cases of carcinomas with different histological grades. When the grades were divided simply into 3 tiers, G1 (well); G2 (moderately); G3 (poorly differentiated), essentially no differences were found between histological grade and growth fraction. In addition, bcl-2 expression, which is known to negatively affect Ki-67 expression, had no correlation with histological grade. Only nuclear p53 overexpression, known to reflect gene alterations, tended to be more common in the higher grade groups. The results indicate that growth fraction does not correlate well with histological grade of human endometrial adenocarcinoma, as far as examined by Ki-67 and bcl-2 immunostains. The p53 gene status may have some significance in histological grade of human endometrial adenocarcinoma, although its role is not always clearly understood.