The racial disparity in outcomes in endometrial cancer: could this be explained on a molecular level?

The racial disparities among patients with endometrial carcinoma have been previously reported. The objective of this study is to analyze and compare the molecular profiles in endometrial cancer in Caucasian and African American patients using a number of known molecular markers.

147 patients diagnosed with endometrial cancer between 1995 and 2001 were included in the study. Patients' demographics, clinical and pathological data were reviewed. Immunohistochemical staining for p53, VEGF, Ki-67 and HIF-1alpha was performed on tissue micro array sections. Tumors' expression of p53, VEGF, Ki-67, and HIF-1alpha was compared based on ethnicity and tumor type (Type I = endometrioid carcinomas and Type II = non-endometrioid carcinomas). Spearman's correlation and Fisher's Exact Tests were used for statistical analysis and Kaplan-Meier, log-rank and Cox regression were used for survival analysis.

97 patients were Caucasian and 50 patients were African American. The mean age was 62 (33-91) years for Caucasian patients and 63.5 (24-89) years for the African American patients. African American patients had more Type II carcinoma than Caucasian patients (P = 0.055). High p53 expression was statistically significant among the African American patients (49% vs. 30%, P = 0.035) versus Caucasian patients. There was no significant difference demonstrated when comparing the VEGF, Ki-67, and HIF-1alpha expression between the racial groups. Survival analysis showed a trend toward a shorter survival in the African American patients compared to the Caucasian patients; median survival 62 versus 77 months (P = 0.061). On the other hand, we did not find a significant difference in survival by ethnicity when we adjusted for tumor histology.

While African American patients with endometrial cancer seem to show a trend toward a shorter survival, this seems to be mainly due to the fact that they have a higher proportion of Type II tumors. The molecular profiles for p53, Ki-67, VEGF and HIF-1alpha expression of histologically matched tumors were similar between the two ethnic groups.