Impact of the COVID-19 Pandemic on Cancer Staging: An Analysis of Patients With Breast Cancer From a Community Practice in Brazil.

PURPOSE: A nationwide lockdown was enforced in Brazil starting in March 2020 because of the COVID-19 pandemic when cancer screening activities were reduced. In this study, we evaluated the impact of the COVID-19 pandemic on breast cancer (BC) diagnosis. METHODS: We extracted data from the medical records of patients age older than 18 years who were diagnosed with BC and started treatment or follow-up in private oncology institutions in Brazil between 2018 and 2021. The primary objective was to compare the stage distribution during the COVID-19 pandemic (2020-2021) with a historical prepandemic control cohort (2018-2019). Early BC was defined as stage I-II and advanced disease as stage IV. RESULTS: We collected data for 11,753 patients with an initial diagnosis of BC, with 6,493 patients in the pandemic (2020-2021) and 5,260 patients in the prepandemic period (2018-2019). We observed a lower prevalence of early-stage BC (63.6% v 68.4%) and a higher prevalence of advanced-stage BC (16.9 v 12.7%), after the onset of the pandemic (both P < .01). This pattern was similar for both estrogen receptor-positive/human epidermal growth factor receptor 2-negative and human epidermal growth factor receptor 2-positive tumors: significantly decreased in the early stage from 69% to 67% and 68% to 58%, respectively, and a considerable increase in advanced-stage disease from 13% to 15% and 13% to 20%, respectively. For triple-negative BC, there was a significantly higher percentage of patients with advanced-stage disease during the pandemic (17% v 11%). Overall, age 50 years or older and postmenopausal status were associated with a greater risk of advanced stage at diagnosis during the pandemic period. CONCLUSION: We observed a substantial increase in the number of cases of advanced-stage BC in Brazil during the COVID-19 pandemic.

Characteristics and prognosis of stage I-III breast cancer subtypes in Brazil: The AMAZONA retrospective cohort study.

OBJECTIVE: To describe stage I-III breast cancer (BC) molecular subtypes and outcomes among a cohort of patients from Brazil. METHODS: AMAZONA study is a retrospective cohort conducted from June 2008 to January 2009 including women of at least 18 years old, with histologically proven breast cancer, diagnosed in 2001 (n = 2198) and 2006 (n = 2714). In this analysis, we included patients who underwent surgery, had stage I-III disease and available pathological information (n = 2296). We estimated molecular subtypes by local immunohistochemical stains. Data was obtained from medical charts and public databases. RESULTS: Mean age at diagnosis was 54 years and 41.1% were younger than 50 years. 23.3% were diagnosed in stage I, 53.5% in stage II and 23.2% in stage III. 80.8% were treated in the public health system. 71.3% had hormonal receptor positive disease, 15.7% were HER-2 positive and 21.1% had triple-negative breast cancer. 55.6% were treated with mastectomy and 96.2% received adjuvant treatment (82.2% chemotherapy). 13.4% of HER-2 positive patients received adjuvant trastuzumab. Overall survival rate at 5 years was 96.84% for stage I, 94.16% for stage II and 70.48% for stage III. Molecular subtypes were independent prognostic factor in stages II and III patients. CONCLUSIONS: Brazilian women have a higher risk of being diagnosed with late stage breast cancer and younger age than in high-income countries. Luminal-like disease is the most common molecular subtype in the country. Triple negative and HER-2 positive had the worst prognosis.