Differences in the Prevalence of Triple-Negative Breast Cancer and the Expression of Selected Tumor Markers in African American and Caucasian Breast Cancer Patients.
Yaser Hussein, Sudeshna Bandyopadhyay, Michele Cote, Bassam Albashiti, Dongping Shi, Amro Almradi, Quratulain Ahmed, Rouba Ali-Fehmi. Wayne State University, Detroit, MI; Karmanos Cancer Institute, Detroit, MI
Background: African-American (AA) breast cancer patients experience higher mortality rates than Caucasian (C) patients. To better understand the reasons for this disparity we compared various clinico-pathologic factors including the prevalence of triple-negative breast cancer (ER-negative, PR-negative, and Her-2-negative) between AA and C breast cancer patients. Differences in the expression of selected markers (Glut-1, EGFR, and COX-2), associated with poor breast cancer outcome were also evaluated, between the two groups.
Design: We identified 513 consecutive patients with invasive breast cancer (317 AA, 196 C), diagnosed at our institution between 2004 and 2006, with a median follow-up period of 42 months. The clinicopathologic findings, and the ER, PR and Her-2 status were reviewed. Immunohistochemical stains for Glut-1, EGFR, and COX-2 were performed on tissue micro-arrays using standardized procedures. Clinical follow up was obtained from our medical records and SEER database. Data was statistically analyzed using Chi-square or Fisher's exact test, and survival was calculated by Kaplan Meier method.
Results: Compared to C, AA patients had significantly larger tumors (p=0.006), higher frequency of grade III tumors and lymph node-positive disease. Triple-negative tumors were significantly more prevalent among the AA patients (34.4%) versus C patients (25%) (p=0.03) and AA patients had significantly poorer overall survival (69% versus 82%; p=0.002). These findings are consistent with previous reports. Interestingly, in this study we also found that the expression of Glut-1, EGFR, and Cox-2 was significantly higher in AA patients (p<0.04) compared to C patients.
Conclusions: In addition to triple-negative tumors, AA patients were more likely than C patients to express Glut-1, EGFR, and COX-2. This data might suggest pathobiological differences between these two groups, which warrants further investigations.
Monday, February 28, 2011 1:00 PM
Poster Session II # 77, Monday Afternoon