PAX2 and Bcl-2 Expression in Early Stage Endometrioid Adenocarcinoma Compared to Endometrial Hyperplasia and the Relationship with Other Prognostic Factors

Purpose: To determine the tissue expression of Bcl-2 and PAX2 in samples from patients with endometrial hyperplasia and early stage endometrial cancer endometrioid endometrial adenocarcinoma and the relationship with other prognostic factors.Methods: Patients with early stage endometrial cancer endometrial adenocarcinoma (the cancer group) and with benign endometrial hyperplasia (the hyperplasia group) diagnosed at a single center between 2009 to 2012 and followed up for at least five years were included.Immunohistochemical staining for Bcl-2 and PAX2 was performed.Microcystic, elongated and fragmented pattern (MELF) numbers and ratios were determined by histopathological re-evaluation of slides from samples from the cancer group.Control and patient groups were compared in terms of Bcl-2 and PAX2 scores.Comparison of Bcl-2 and PAX2 scores in relation to different prognostic factors, such as tumor size, myometrial invasion, lymphovascular stromal invasion, myometrial invasion pattern and in tissues neighboring the cancer tissues were performed.Results: Mean PAX2 expression scores (0.58±1.3 vs 4.3±1.06,p<0.01) were significantly lower in cancer group (n=57) compared to the hyperplasia group (n=34).Similarly, mean Bcl-2 expression scores were significantly lower in the cancer group (2.2±1.6 vs 4.06±1, p<0.01).MELF pattern was positive in 60% of the cases in cancer group compared to 10.6% in the hyperplasia group (p<0.01).Median Bcl-2 scores were higher in MELF positive cases (M=3) compared to MELF negative cases (M=2, p=0.04).In addition, median PAX2 scores were higher in MELF positive cases compared to MELF negative cases [2 (range here) vs 0 (range here), p=0.007]. Conclusion:Bcl-2 and PAX2 appear to be important in differentiating early stage endometrial cancer endometrioid cancer tissue from hyperplastic endometrial tissue.Their expressions were found to be similar in different prognostic subgroups.