Risk factors and survival of triple-negative breast cancer among breast cancer patients: Ten-year cross-sectional study in the southwestern Iranian population.

BACKGROUND: Breast cancer results from genetic and epigenetic mutations, contributing significantly to cancer-related morbidity and mortality. This study aimed to determine the prevalence and survival rates of triple-negative breast cancer (TNBC) among breast cancer patients in southwestern Iran over a ten-year period.

METHODS: This retrospective cross-sectional study aims to assess prognostic factors associated with survival in women diagnosed with breast cancer in Iran's southwestern region over a ten-year period (2007-2017). Data were collected from patients who visited the Clinical Oncology Department at Golestan Hospital in Ahvaz (the breast cancer center of the Southwestern country). The study enrolled women diagnosed with TNBC using a census method and data from medical records. The primary outcome (survival rates) and secondary outcomes (demographic data, diagnostic stages, and three receptors estrogen receptors [ER], progesterone receptor [PR], human epidermal growth factor receptor 2 [HER2] status) were collected.

RESULTS: Breast cancer was diagnosed in 2641 women over ten years; TNBC was diagnosed in 227 individuals (8.59%). Statistical analysis revealed a significant correlation between negative ER status and TNBC ( p  > 0.05). Furthermore, the prevalence of TNBC differed significantly from that of other types of breast cancer ( p  = 0.0001). The variables of age, HER2, PR, and TNBC grade did not differ significantly ( p  > 0.05). The overall disease-free survival rate over 5 years was 88.1%, while the rate for individuals without recurrence was 77.97%.

CONCLUSION: This study highlights a differentially low incidence of TNBC in the southwestern part of Iran when compared to other regions; genetic or epigenetic influences may explain this discrepancy. ER-negative status is a crucial prognostic indicator in diagnosing TNBC. The incidence of this disease is expected to rise by 100% in 2 years and 77.97% in 5 years.