The Impact of Covid-19 on the population-based cancer screening programmes. Basque Country (Spain)

Background The Breast Cancer (BCS) and Colorectal Cancer (CRCS) screening programmes are consolidated in the Basque Country with coverage and participation rates according to EU recommendations. The Cervical Cancer Screening (CCS) carried out in 2018 achieved an appropriate migration from an opportunistic programme an coverage in 2019. The pandemic disrupted the invitations and participation because of the lockdown and procedures offered because of Covid-19 safety measures since then. Objective: Analysis of the expected impact of the pandemic on early detection of advanced lesions and cancer. Methods Retrospective cohort study including all invitations 2016-2020 and results estimated (E) and observed (O) in 2020 without and with pandemic. Analysis R v 4.0. Description of measures taken into account to minimize the decrease of activity. Results Eligible population in BCS O/E were 54.4% (CI 95%: 41.0-41.6; p < 0.05) (85,574 vs 150,534), estimating 202 BC (35 in situ and 167 advanced) not detected. In CRCS eligible population O/E were 39.2% (CI 95%: 44.9-45.3; p < 0.05) (119,851 vs 257,889), estimating 1,695 advanced neoplasias (1,540 advanced adenomas and 154 invasive cancer) not detected. The CCS invitation had an important delay, with a 30% of target population invited (42,654 vs 142,180 women). Participation rate showed a slight decrease in the three programmes. The main measures implemented to minimize the disruption effects were: prioritization of confirmed diagnosis, increased activity to recover from the delays in 2020-2021 and the establishment of protocols to decrease intensive surveillance in case of post-colonoscopy. Conclusions The Pandemic has significantly affected the three population-based programmes, showing a reduction of its benefits in incidence and mortality at medium-long term as the COVID-19 and Cancer Global Modelling Consortium (CCGMC) appointed and published. Stakeholders should take into consideration the quick recovery of them. Key messages The benefits of the cancer screning programmes are seriously affected. It is needed to measure the COVID-19 consecuencies in cancer screening programmes.