The impact of sociodemographic factors and health insurance coverage in the diagnosis and clinicopathological characteristics of breast cancer in Brazil: AMAZONA III study (GBECAM 0115)

Purpose In Brazil, the available cancer registries are deficient in number and quality and, hence, little information is known regarding sociodemographic, clinicopathological characteristics, treatment patterns, and outcomes of breast cancer (BC) patients. We performed the AMAZONA III/ GBECAM 0115 study and in this analysis, we describe patients’ characteristics at diagnosis and their association with health insurance type. Methods This is a prospective cohort study developed in 23 sites in Brazil including women with newly diagnosed invasive BC from January 2016 to March 2018. In order to compare healthcare insurance type, we considered patients who were treated under the Brazilian public health system as publicly insured, and women who had private insurance or paid for their treatment as privately insured. Results A total of 2950 patients were included in the study. Median age at diagnosis was 53.9 years; 63.1% were publicly insured. The majority of patients (68.6%) had stage II–III breast cancer and ductal carcinoma histology (80.9%). The most common breast cancer subtype was luminal A-like (48.0%) followed by luminal B-HER2 positive-like (17.0%) and triple-negative (15.6%). Luminal A was more frequent in private (53.7% vs. 44.2%, p < .0001) than public, whereas Luminal B HER2-positive (19.2% vs. 14.2%, p = 0.0012) and HER2-positive (8.8% vs. 5.1%, p = 0.0009) were more common in patients with public health system coverage. Only 34% of patients were diagnosed by screening exams. Privately insured patients were more frequently diagnosed with stage I disease when compared to publicly insured patients; publicly insured patients had more stage III (33.5% vs. 14.7%; p -value < 0.0001) disease than privately insured ones. Breast cancer was detected by symptoms more frequently in publicly than in privately insured patients (74.2% vs 25.8%, respectively; p -value < 0.0001). Conclusions Patients with public health coverage were diagnosed with symptomatic disease, later stages and more aggressive subtypes when compared to privately insured patients.