Análise de sobrevida de pacientes com câncer de mama e metástase óssea tratados com Trastuzumabe versus outros esquemas em uma coorte de 8 anos no Brasil

Abstract

Breast cancer is the most prevalent tumor in women worldwide when excluding non-melanoma skin cancer, and this is no different in Brazil. There is limited literature on its main prognostic factors, as well as on the benefit of using Trastuzumab for Overall Survival (OS) in the Brazilian population that developed bone metastasis. More than 70% of the Brazilian population is treated by the SUS (public health system), and its use by the SUS began in 2013 in the setting of non-metastatic disease. Since it is a high-cost medication, it is necessary to conduct this study to evaluate its actual benefit in the Brazilian population. Method: This is an observational, non-concurrent cohort study that evaluated the use of Trastuzumab in patients diagnosed with non-metastatic breast cancer, treated within the SUS from 2008 to 2015, who developed bone metastasis as the first event in their disease progression. The Kaplan-Meier method was used to estimate overall survival and use the Cox proportional hazards model to assess prognostic factors. Results: A total of 4,450 patients were included in the overall cohort, which showed that younger patients, those with more advanced staging, treated with chemotherapy, and who underwent neoadjuvant therapy had worse overall survival. The use of Trastuzumab demonstrated a significant gain in OS, with approximately 75% of women being alive at 5 years in the group that received Trastuzumab compared to only 50% in the group that did not receive. Conclusion: This is one of the first observational studies showing a gain in overall survival with the use of Trastuzumab in the Brazilian population diagnosed with early-stage breast cancer who progressed with bone metastasis, treated within the public healthcare system.