Real-world outcomes of women with metastatic breast cancer in visceral crisis treated with chemotherapy: a 15-year cohort from Brazil

Introduction: Visceral crisis (VC) in metastatic breast cancer (MBC) is defined as a severe organ dysfunction related to metastatic disease. The cornerstone of treatment for VC relies on polychemotherapy, particularly in low-and middle-income countries, where it often represents the only available therapeutic option. This study aims to assess survival outcomes of palliative chemotherapy (CT) for VC in a real-world scenario. Methods: Data were retrospectively collected from patients with MBC diagnosed with VC between 2008 and 2022 in a large cancer center in Brazil. Survival analyses were performed using the Kaplan-Meier method. Prognostic factors were evaluated through univariate and multivariable analyses using the Cox regression model. Results: A total of 146 patients with VC were included. The predominant type of VC was pulmonary (36.3%), hepatic (32.2%) and bone marrow infiltration (19.2%). VC management was based on combination CT (51.4%), while 27.4% were treated with monochemotherapy and 20.6% received best supportive care (BSC). The median overall survival (mOS) for the entire population was 2.17 months. Treatment for VC in the first-line setting was associated with a mOS of 5 months. In the multivariate analysis, hepatic VC and the absence of active oncological therapy (BSC) were significantly associated with mortality. Conclusion: Patients with MBC in VC have a poor prognosis even when treated with polychemotherapy. Proper prognostication is crucial for identifying patients who may benefit from active systemic therapy while carefully avoiding potentially futile strategies. Prospective trials including patients with VC criteria are needed to evaluate the efficacy and safety of CT and other emerging therapies in this scenario.