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.

Outcome of cerebral arteriovenous malformations after linear accelerator reirradiation.

BACKGROUND: The aim of this study was to evaluate the clinical outcome of patients undergoing single-dose reirradiation using the Linear Accelerator (LINAC) for brain arteriovenous malformations (AVM). METHODS: A retrospective study of 37 patients with brain AVM undergoing LINAC reirradiation between April 2003 and November 2011 was carried out. Patient characteristics, for example, gender, age, use of medications, and comorbidities; disease characteristics, for example, Spetzler-Martin grading system, location, volume, modified Pollock-Flickinger score; and treatment characteristics, for example, embolization, prescription dose, radiation dose-volume curves, and conformity index were analyzed. During the follow-up period, imaging studies were performed to evaluate changes after treatment and AVM cure. Complications, such as edema, rupture of the blood-brain barrier, and radionecrosis were classified as symptomatic and asymptomatic. RESULTS: Twenty-seven patients underwent angiogram after reirradiation and the percentage of angiographic occlusion was 55.5%. In three patients without obliteration, AVM shrinkage made it possible to perform surgical resection with a 2/3 cure rate. A reduction in AVM nidus volume greater than 50% after the first procedure was shown to be the most important predictor of obliteration. Another factor associated with AVM cure was a prescription dose higher than 15.5 Gy in the first radiosurgery. Two patients had permanent neurologic deficits. Factors correlated with complications were the prescription dose and maximum dose in the first procedure. CONCLUSION: This study suggests that single-dose reirradiation is safe and feasible in partially occluded AVM. Reirradiation may not benefit candidates whose prescribed dose was lower than 15.5 Gy in the first procedure and initial AVM nidus volume did not decrease by more than 50% before reirradiation.