Impact of delayed screening invitations on screen-detected and interval cancers in the Dutch colorectal cancer screening programme: individual-level data analysis.

OBJECTIVE: To assess the impact of delayed invitation on screen-detected and interval colorectal cancers (CRC) within a faecal immunochemical testing (FIT)-based CRC screening programme. DESIGN: All individuals that participated in 2017 and 2018 with a negative FIT and were eligible for CRC screening in 2019 and 2020 were included using individual-level data. Multivariable logistic regression analyses were used to assess the association between either the different time periods (ie, 'before', 'during' and 'after' the first COVID-19 wave) or the invitation interval on screen-detected and interval CRCs. RESULTS: Positive predictive value for advanced neoplasia (AN) was slightly lower during (OR=0.91) and after (OR=0.95) the first COVID-19 wave, but no significant difference was observed for the different invitation intervals. Out of all individuals that previously tested negative, 84 (0.004%) had an interval CRC beyond the 24 months since their last invitation. The time period of invitation as well as the extended invitation interval was not associated with detection rates for AN and interval CRC rate. CONCLUSION: The impact of the first COVID-19 wave on screening yield was modest. A very small proportion of the FIT negatives had an interval CRC possibly due to an extended interval, which potentially could have been prevented if they had received the invitation earlier. Nonetheless, no increase in interval CRC rate was observed, indicating that an extended invitation interval up to 30 months had no negative impact on the performance of the CRC screening programme and a modest extension of the invitation interval seems an appropriate intervention.

Impact of COVID-19 and suspension of colorectal cancer screening on incidence and stage distribution of colorectal cancers in the Netherlands.

Many countries had to suspend their colorectal cancer (CRC) screening programme as a result of the COVID-19 pandemic. This eventually may lead to postponed diagnoses of premalignant lesions and CRC, resulting in increased incidence or more advanced CRCs rates. This study aimed to assess the impact of the COVID-19 pandemic on incidence and stage distribution of CRCs in the Netherlands, by monitoring CRC diagnoses and stage distribution in the months before, during and after the first COVID-19 wave. Data on incidence and stage distribution of CRCs of individuals aged 55-75 years in 25 hospitals in the Netherlands were extracted from the Netherlands Cancer Registry. The observed incidence after the suspension (March 2020-December 2020) was compared to the expected incidence in the same period. In the period April to June 2020, we observed the largest decrease in the total incidence of CRC. We found that 48% of the decrease was due to stage I, 23% due to stage II, 23% due to stage III and 5% due to stage IV. After gradually resuming screening mid May 2020, we observed an increase in CRC diagnoses from July 2020 onwards. As of October 2020, the observed number of diagnoses was higher than the expected number. As the decrease was mainly limited to stage I CRCs, it seems that the temporary suspension of the CRC screening programme due to the COVID-19 pandemic will have a minimal long-term impact on stage distribution and CRC mortality.