A high apoptotic index occurs in subtypes of endometrial adenocarcinoma associated with a poor prognosis

A study was carried out to determine the apoptotic index (AI) in cases of endometrial adenocarcinoma that are usually associated with a poor prognosis, and to identify in the AI in these cases differs from the AI's in grade I and II endometrial adenocarcinoma. The apoptotic index (defined as the percentage of morphologically identified apoptotic cells and apoptotic bodies in counting 3000 tumor cells) was calculated for five grade III endometrial adenocarcinomas of no specific type (NST), five clear cell adenocarcinomas (CCC), three high grade uterine papillary serous carcinomas (UPSC) and one undifferentiated carcinoma of the endometrium. Overall a higher mean AI (6.3%) was identified in these poor prognosis neoplasms than in 13 grade I and II endometrial adenocarcinomas (mean AI 2.7% p < 0.0001). The apoptotic index was highest in the undifferentiated carcinoma (AI = 9.7%). The mean AI for the cases of UPSC, CCC and grade III endometrioid (NST) adenocarcinomas were 7.4%, 5.9% and 5.2% respectively. There was no evidence of a statistically significant difference in the AI in these poor prognosis groups (Kruskall Wallis test p = 0.45). Although the results show that a high AI is a feature of poor prognosis endometrial carcinoma, no distinction in AI was demonstrated in the subtypes examined.