Abstract B121: Pathologic characteristics of African American women with breast cancer treated at the DoD’s Murtha Cancer Center: Why survival cancer is not disparate to European American women when treated within the US military healthcare system
Authors: Lovejoy Leann A , Shriver Craig D , Ellsworth Rachel E 
Published: September 2020

(AAW) are significantly higher than in European American women (EAW), including a 42% higher mortality detected in AAW in the SEER database and a worse breast cancer-free interval for AAW in The Cancer Genome Atlas. In contrast, survival analysis from women treated within the Department of Defense Military Healthcare System (DoD MHS) healthcare system found that AAW and EAW with early-stage breast cancer had similar survival rates. In this study, we evaluated pathological factors of AAW treated within the Murtha Cancer Center at Walter Reed National Military Medical Center to identify factors associated with this lack of disparate outcomes within the DoD MHS. Methods: Between 2001-2018, 346 AAW and 746 EAW treated at MCC/WRNMMC enrolled in the Clinical Breast Care Project(CBCP). All diagnoses were performed by a single breast pathologist and pathological characteristics including stage (AJCC Cancer Staging Manual seventh edition), grade, size, lymph node, hormone receptor and HER2 status were recorded. Data were analyzed using chi-square and log-rank analyses and Student t-tests with a P-value &lt;0.05 used to define significance. Results: African American women comprised 29% of the women with invasive breast cancer in the CBCP. The average age at diagnosis was 56.1 years in AAW and 58 years in EAW and the frequency of women diagnosed &lt;40 years of age did not differ significantly (9% AAW, 7% EAW). Tumor stage (P=0.004), grade (P&lt;0.001), size (P&lt;0.001), subtype (P&lt;0.001) and lymph node status (P=0.028) all differed significantly between populations. Breast tumors from AAW were significantly less likely to be diagnosed at stage I compared toEAW (43% AAW, 55% EAW), and more likely to be lymph node positive (40% AAW, 33% EAW) and size T2 (34% AAW, 26% EAW). Biologically, AAW were more likely to have poorly differentiated (43% AAW, 28% EAW) and triple negative (24% AAW, 14% EAW) tumors. Seven percent of AAW and 6% of EAW died of disease with no significant difference in time to death (4.22 years AAW, 4.67 EAW). Neither 5-year nor 10-year survival differed significantly between populations. Conclusion: These data across all stages of breast cancer diagnosis support an earlier finding in early-stage patients that survival disparities, common in the general population, are not detected for AAW treated within the DoD MHS. Critically, this survival advantage for AAW treated at MCC/WRNMMC exists against a background of AAW having tumors with less favorable pathological characteristics, as seen in the US general population. Evaluation of pre- and post-diagnostic care within DoD MHS should be performed to determine how breast care within an equal-access healthcare setting is received by AAW patients and the DoD MHS can be used as a model of care to reduce breast cancer disparities within the US general population.

Citation Format: Leann A Lovejoy, Craig D Shriver, Rachel E Ellsworth. Pathologic characteristics of African American women with breast cancer treated at the DoD’s Murtha Cancer Center: Why survival cancer is not disparate to European American women when treated within the US military healthcare system [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr B121.