Purpose: As a result of its epidemiologic and therapeutic aspects, metastatic breast cancer (MBC) is a highly relevant clinical condition. This study aimed to estimate overall survival (OS) in women with de novo MBC in a Brazilian population.
Patients and methods: Patients were identified in the Goiânia population-based cancer registry between 1995 and 2011. All women with metastatic disease at diagnosis were included in the study. OS was analyzed at 5 and 10 years of follow-up. We used the Kaplan-Meier estimator and Cox regression for statistical analysis.
Results: Over the 16-year period covered by the study, 5,289 women were diagnosed with breast cancer in Goiânia. Of these, 277 women (5.2%) had MBC. OS rates at 5 and 10 years were 19.9% and 7.3%, respectively. The mean OS time of women treated in the public health system was 7.5 months shorter than in women who had private health care (19.7 v 27.2 months, respectively). In the univariable analysis, the following factors were statistically significant for OS: T3/4 staging, histologic grade 3, progesterone receptor status, tumor phenotype, breast surgery, CNS metastasis at initial presentation, and surgery for resection of metastasis. In multivariable analysis, initial CNS metastasis (hazard ratio, 3.09; 95% CI, 1.16 to 8.19) and breast surgery (hazard ratio, 0.45; 95% CI, 0.25 to 0.78) remained independent prognostic factors.
Conclusion: OS was lower than rates found in specialist centers in Brazil and in developed countries. Several intrinsic and extrinsic factors were significant in predicting OS. Despite the difference in the 5-year survival rate, the type of access to health care was not significant in the multivariable analysis of the entire period.