CN31 - Social disparities in the survival of women with breast cancer in Brazil

Background

In Brazil, according to the National Cancer Institute (INCA), the estimate for the three-year period from 2023 to 2025 is 73,610 new cases of breast cancer, representing a tumor with a higher incidence in regions with a higher Human Development Index. Furthermore, the highest estimated risk is observed in the Southeast Region of Brazil, at 84.46 per 100 thousand women. The aim of this study was to investigate the association between sociodemographic factors and the survival of women diagnosed with breast cancer in all hospitals that make up the Oncological Care Network in the state of Espírito Santo, Brazil, between 2000 and 2016.

Methods

This is an observational hospital-based retrospective cohort study, covering databases extracted from Hospital-based Cancer Registries and the Mortality Information System of the state of Espírito Santo, Brazil, comprising 12,096 patients with breast cancer. The cases were divided into death from breast cancer, death from other causes and survivors within 5 years. For 5-year survival, the Kaplan-Meier and LogRank methods were used, in addition the Cox proportional hazards model for specific cause of death was used in the multivariate analysis.

Results

The hospital cohort revealed that 8,184 (67.66%) of women survived to the end of treatment, 2,947 (24.28%) died from breast cancer, and 9,075 (8.06%) died from other causes. Overall specific survival was 82% at 5 years. Multivariate analysis revealed that race is a risk factor for specific death from breast cancer, where black women have a 60% higher risk of specific mortality from breast cancer than white women (HR=1.601; 95% CI: 1.303-1.967 ; p<0.001). Similarly, marital status was also a risk factor for specific death, in which single women have a 31% higher risk of specific mortality from breast cancer than married women (HR=1.314; 95%CI:1.188-1.454; p<0.001).

Conclusions

There is social disparity in 5-year breast cancer survival, mediated mainly by age at diagnosis, race/color, marital status and education level. These findings point to the need to expand the coverage and quality of the breast cancer screening program and facilitate access to early diagnosis and treatment, with a view to reducing health disparities and inequities.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

L.C. Lopes-Júnior.

Funding

Fundação de Amparo à Pesquisa do Espírito Santo - FAPES/CNPq/Decit-SCTIE-MS/SESA N° 09/2020 – PPSUS.

Disclosure

All authors have declared no conflicts of interest.