Breast cancer treatment access disparities: A retrospective cohort study of breast cancer in patients treated at a high-complex cancer center in southern Brazil.
Authors: Cacilhas Pedro , Rosa Daniela Dornelles , de Freitas Pedhro , Thomas Gustavo , Fabra Lucas Fernando , Zelmanowicz Alice 
Published: May 2024

e13689 Background: More than seventy-three thousand new breast cancer cases are expected in Brazil for the year 2023, representing the most common malignancy in this country. Delaying time to treatment initiation has been associated with increased risk of worse outcomes. The Brazilian government developed several initiatives to accelerate the access of cancer patients to treatment in an adequate time-bound. One of these is a federal law defining that oncological treatment should begin within 60 days of pathological diagnosis. Methods: This retrospective study analyzed data of newly diagnosed breast cancer patients in 2022–2023 in Hospital de Clinicas de Porto Alegre (HCPA), a public hospital in Porto Alegre, Brazil. The primary objective was to build a predictive model of risk factors that could delay the time to first treatment beyond 60 days from diagnosis. The present analysis describes the socio-demographic characteristics of these patients and explores their impact on the time to oncologic treatment initiation. This project was approved by the Ethics and Research Committee (registration CAAE 71160423.7.0000.5327). Results: 184 patients who started their oncological treatment between 2022-2023 in HCPA were enrolled; 32 patients (17,3%) had their first treatment after 60 days from the diagnosis while 152 (82,7%) were treated before 60 days; 106 (57,3%) patients had studied up to elementary school and 32 (17,3%) were non-white; 53 patients (23%) had been submitted to biopsy outside HCPA. Patients who started their first treatment before 60 days had a mean of 38 days from diagnosis to first treatment while those treated after 60 days had a mean of 75,6 days. To evaluate how socio-demographic factors impacted the time to treatment initiation, a multivariate Poisson log-linear model adjusted for race, city of residence, stage of the disease, and type of first treatment considered different variables. Higher educational level had a statistically significant effect, with a rate ratio (RR) of 0.32 (95% CI 0.157 - 0.650, p < 0.05). We also found that performing biopsy in our institution instead of doing it elsewhere had a statistically significant impact on the time to first treatment, with an RR of 0.512 (95% CI 0.274 - 0.957, p = 0.036). Ethnicity was not related to delay of treatment (p-value=0.125). Conclusions: This study identified that socio-demographic factors are crucial to guarantee the appropriate time to start treatment for breast cancer patients in a middle-income country. Higher educational level had a positive impact on time-to-treatment initiation, as well as to perform biopsy in the same institution patients were treated. In this first analysis, ethnicity, clinical staging, and type of first treatment did not meet the statistical criteria to be considered relevant and the accrual of more patients is needed for further conclusions.