Abstract P5-12-05: Racial and gender disparity in breast cancer: A review on African American men
Authors: Miles KC , Onyewu SC , Obirieze A , Frederick WAI , Dewitty R , Leffall LD , Horton S , Wilson L 
Published: August 2014

Background: Secondary to their comparable racial and socio-demographic background, African American (AA) men and women with breast cancer are expected to have similar outcomes. However, there is a paucity of data demonstrating gender-specific differences in breast cancer across racial/ethnic groups. Our objective is to investigate potential differences between AA men, AA women and White men with breast cancer by evaluating risk factors using a population-based tumor registry.

Methods: A retrospective review of the Surveillance Epidemiology and End Results (SEER) database from 1988 to 2008 was conducted. We identified AA men and AA women aged 20 years or older with a primary breast cancer diagnosis or in whom the index breast cancer is the first cancer. A similar group of White men were included to serve for comparison. All available treatment modalities were reviewed. Bivariate analysis of patient characteristics, tumor grade, stage, hormonal assay, and treatment modality was performed using Chi squared test. Survival was estimated and Cox proportional model was used to investigate survival differences comparing AA men, AA women and White men (with AA men as reference), adjusting for age, year of diagnosis, tumor characteristics, as well as treatment received. Subset analyses were done within stage strata.

Results: We reviewed 62 758 patient records comprising 506 (0.81%) AA male, 59 234 (94.38%) AA female and 3 018 (4.81%) White males. Most were 50 years or older (57.5%), married (39.4%), had invasive ductal carcinoma (61.9%) and localized disease (42.5%). Mean age at diagnosis was 59 (±11), 55 (±12) and 63 (±11) years for AA males, AA females and White males, respectively. Men were more likely to have moderately differentiated tumors (37.6% and 40.4% for AA males and White males, respectively) compared to AA women who were more likely to have poorly differentiated tumors (39.2%) (p&lt;.001). AA males had more regional disease (39.5%) compared to AA females and White males who had more localized disease (42.6% and 41.5%, respectively). Incidence of distant metastasis was highest among AA men (10.9%) compared to their AA female (6.10%) and White male (5.8%) counterparts (p&lt;.001). Men received more modified radical mastectomies (61.2% and 62.6% for AAs and Whites, respectively) and women had more partial mastectomies (56.4%). The 5- and 10-year survival was 78% (95% CI .73-.82) and 66% (95% CI .59-.72) for AA men, 80% (95% CI .80-.81) and 73% (95% CI .72-.73) for AA women, 88% (95% CI .86-.89) and 79% (95% CI .77-.81) for White men. Overall, White men were 24% less likely to die from breast cancer compared to AA men (HR 0.76; 95% CI .62-0.94), while the survival difference was not significant when compared to AA women (HR: 0.98; 95% CI: 0.81-1.19). Similarly, among patients with regional disease, White men had significantly better survival (HR: 0.63; 95% CI: 0.46-0.48) compared to AA men.

Conclusion: Using a large population-based database, our study demonstrates absence of gender specific difference in breast cancer survival among African Americans. However, AA men were found to have larger tumors, worse stage, and despite presenting with similar grade and receiving similar treatment as White males, had worse outcome.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-12-05.