Impact of covid-19 pandemic on the incidence and treatment of gliomas

Abstract

Background: the COVID-19 pandemic has affected neuro-oncology services around the world. Our objective was to determine the influence of the COVID-19 pandemic on the incidence, grade shift, therapy and delay of the therapy of gliomas.
Methods: based on data of clinical cancer registry Regensburg, years 2015-2019 were compared with pandemic years 2020, 2021.
Results: during the investigation period from 2015 to 2021 the initial diagnosis of glioma (ICD-10 diagnosis C71) was made in 1008 patients. WHO grade 3 and 4 tumors requiring urgent treatment had 142 (14,1%) and 744 (73,8%) patients, respectively. The analysis of the annual number of newly diagnosed cases from 2015 to 2021 showed no clear difference between the years before and during the pandemic. In March and October 2020 was observed a not statistically significant decrease of new cases of 37,5% (March) and 35,5% (October) compared to the comparison months 2015-2019. The prevalence of WHO grade 4 tumors remained stable over the course of the study. The number of newly diagnosed WHO grade 4 brain tumors remained comparable in the study period 2015-2019 (73,2%,) to the number in 2020 (73,7%, p=0,911) and 2021 (75,3%, p=0,597). A monthly analysis of the number of operations on gliomas WHO grade 3 and 4 in 2020 vs. 2015-2019 showed a significant regression until the middle of the year 2020. The number of operations increased rapidly in July 2020. The quarterly comparison 2020 vs. 2015-2019 represents statistically significant decrease in surgeries in patients with WHO grade 3 and 4 gliomas in the first and second quarter of 2020.
Conclusion: with the exception of a decrease in the number of surgical interventions in the first quarter of 2020, we have not identified any significant changes in the diagnosis and treatment of HGG during the pandemic.