Disparities in Triple Negative Breast Cancer Among Hispanic Population Living in Latin America Versus the United States.

Introduction: Triple-negative breast cancer (TNBC) has a prevalence of 12%-24% in the Hispanic population. Previous research has demonstrated that disparities in healthcare access significantly influence patient outcomes. We aimed to compare the clinicopathological characteristics and outcomes of Hispanic females with TNBC living in Latin America (HPLA) to the Hispanic population in the United States (HPUS).

Methods: We evaluated two retrospective cohorts: patients diagnosed with TNBC at the Instituto Nacional de Enfermedades Neoplasicas, Lima, Peru, during 2000-2015, and HPUS patients with TNBC from the Surveillance, Epidemiology, and End Results Program (SEER).

Results: A total of 2007 HPLA and 8457 HPUS patients were included. The HPLA patients were younger and more frequently lived in nonmetropolitan areas. HPLA had higher T and N (p < 0.001) stages. HPLA patients were more likely to present with Stage III disease (51.6% vs. 20.8%), while Stage IV presentations were similar 6.6% vs. 6.8%. HPLA patients with Stages I and II more frequently underwent mastectomy compared to HPUS (56.2 vs. 48.0%). HPLA patients received neoadjuvant chemotherapy (p < 0.001), adjuvant chemotherapy (p < 0.001), and radiotherapy (p < 0.001) more often. While early breast cancer stages had similar overall survival (OS) rates for both populations, HPLA patients had worse 5-year OS rates compared to HPUS patients in Stages III (39.9% vs. 52.3%, p < 0.001) and IV (4.6% vs. 10.7%, p < 0.001).

Conclusions: Hispanic females living in Latin America were more frequently diagnosed with advanced stages of TNBC and more often underwent mastectomy, even in early-stage disease. When analyzing advanced stages, HPLA had worse OS rates compared to HPUS.