Overall survival analysis of women with breast cancer: a 27-year historical cohort

Abstract

Objective: The objective of this study was to analyze the overall survival and prognostic factors of women with breast
cancer in the city of Goiânia, based on a 27-year historical cohort. Methodology: This is a retrospective cohort study of
overall survival carried out from 1988 to 2015. Data were collected from the Population-Based Cancer Registry of Goiânia,
Goiás, Brazil. Survival curves were performed using the Kaplan-Meier method and the log-rank test. Multiple Cox regression analysis was also used. The significance level adopted was 5% (p<0.05). The research was approved by the Ethics
Committee. Results: Among the 7395 women included in the study, there was a predominance of the age group of
50–69 years (45.4%), localized disease (62.4%), and pure luminal phenotype (50.1%). The median survival was 122 months,
and the overall survival at 5 and 10 years was 83.1% and 65.5%, respectively. Regarding race/color, white women had a
longer survival rate compared with black women (average of 120 vs. 110 months). In the Cox regression analysis, the following factors were associated with reduced overall survival: age greater than 70 years (HR 1.33; p<0.001), histological grade
III (HR 1.21; p=0.042), recipient of negative estrogen (HR 1.26; p=0.010), negative progesterone receptor (HR 1.47; p=0.041),
triple-negative tumor phenotype (HR 2.36; p=0.008), and regional disease extension (HR 1.73; p=0.023) or metastatic (HR
2.67; p=0.012). Conclusion: In the period analyzed, the overall survival of women with breast cancer was 83.1% in 5 years
and 65.5% in 10 years. Several clinical, biological, and tumor factors influenced the prognosis in this population.