Comparative immunohistochemical study of endometrioid and serous papillarycarcinoma of endometrium

Objective: The aim of this study was to determine whether immunohistochemic al analysis of molecular parameters can provide an alternative method for c lassification of endometrial cancer cases according to their aggressiveness . Methods: Sixty-four cases of endometrial carcinoma were assigned to three g roups: group I - 28 cases of endometrioid well and moderately differentiate d (G(1)-G(2)) carcinoma; group IL-14 cases of endometrioid poorly different iated (G(3)) carcinoma; group III - 22 cases of serous papillary endometria l cancer. Immunohistochemistry was used to determine the existence of estro gen receptors (ER). progesterone receptors (PR), and the expression of bcl- 2, p53, HER-2/neu and Ki-67. Results: There was a significant difference in the immunohistochemical prof ile of the studied molecular parameters comparing the three study groups. T he endometrioid G(1)-G(2) cases (group I) were characterized by increased i mmunoreactivity for ER and PR (85.7% and 78.6%, respectively). increased im munoreactivity for bcl-2 (42.8%) and low expression of p53 (14.3%) and HER- 2/neu (14.3%). In contrast to group I cases, the serous papillary endometri al cancer cases (group III) were characterized by immunonegativity for ER, PR and bcl-2 and high immunoreactivity for p53 (81.8%) and HER-2/neu (45.4% ). The endometrioid G(3) cases (group II) demonstrated an intermediate immu noprofile, characterized by immunonegativity for ER, PR and HER-2/neu, low immunoreactivity for bcl-2 (7.1%) and high expression of p53 (57.1%). The e xpression of Ki-67 did not differ significantly comparing the different cas es of endometrial cancer. Conclusion: This study provides evidence that the immunohistochemical analy sis of endometrial carcinoma differentiates between different grades and hi stological types, thus being useful in the distinction of high risk cases.