The impact of episodic screening interruption: COVID-19 and population-based cancer screening in Canada

Abstract

Background Population-based cancer screening can reduce cancer burden but was interrupted temporarily due to the COVID-19 pandemic. We estimated the long-term clinical impact of breast and colorectal cancer screening interruptions in Canada using a validated mathematical model. Methods We used the OncoSim breast and colorectal cancers microsimulation models to explore scenarios of primary screening stops for 3, 6, and 12 months followed by 6–24-month transition periods of reduced screening volumes. For breast cancer, we estimated changes in cancer incidence over time, additional advanced-stage cases diagnosed, and excess cancer deaths in 2020–2029. For colorectal cancer, we estimated changes in cancer incidence over time, undiagnosed advanced adenomas and colorectal cancers in 2020, and lifetime excess cancer incidence and deaths. Results Our simulations projected a surge of cancer cases when screening resumes. For breast cancer screening, a three-month interruption could increase cases diagnosed at advanced stages (310 more) and cancer deaths (110 more) in 2020–2029. A six-month interruption could lead to 670 extra advanced cancers and 250 additional cancer deaths. For colorectal cancers, a six-month suspension of primary screening could increase cancer incidence by 2200 cases with 960 more cancer deaths over the lifetime. Longer interruptions, and reduced volumes when screening resumes, would further increase excess cancer deaths. Conclusions Interruptions in cancer screening will lead to additional cancer deaths, additional advanced cancers diagnosed, and a surge in demand for downstream resources when screening resumes. An effective strategy is needed to minimize potential harm to people who missed their screening.

Two-month stop in mammographic screening significantly impacts on breast cancer stage at diagnosis and upfront treatment in the COVID era

“…These results confirm the estimates obtained through the mathematical models of Yong et al 15 and Sharpless 16 in terms of increased advanced stages at diagnosis. Additionally, since treatment of more advanced cancers generally involves more widespread use of systemic therapy and invasive surgery, we may also conclude that these delays in cancer diagnosis could be associated with increased morbidity and higher costs for our national health system.…”

“…14 Although asymptomatic women who have skipped their screening mammogram because of COVID-19 are recommended to reschedule the check preferably within 3 months, 11 the real impact of temporary mammographic screening suspension on BC outcomes remains uncertain. Yong et al 15 have recently estimated the long-term clinical impact of BC screening interruptions in Canada using a validated mathematical model. The authors found that a 3-month interruption in BC screening could increase cases diagnosed at advanced stages and cancer deaths in 2020-2029.…”

“…Yong et al. 15 have recently estimated the long-term clinical impact of BC screening interruptions in Canada using a validated mathematical model. The authors found that a 3-month interruption in BC screening could increase cases diagnosed at advanced stages and cancer deaths in 2020-2029.…”

Cervical screening during the COVID-19 pandemic: optimising recovery strategies

“… 1 These disruptions are expected to result in an excess of advanced cancer diagnoses and deaths in the coming years. 2 , 3 , 4 , 5…”

Reply to: Oncologic thoracic surgery during the second wave of COVID‐19 pandemic: How to be ready for the storm

“…Their interruptions or even delays can lead to severe consequences in the coming years for both patients' outcomes and financial sustainability of healthcare systems. 4,5 Regarding future research outlooks, it will be important to comprehensively evaluate the overall consequences of the COVID-19 pandemic on surgical oncology practice, also to estimate its potential impact on cancer care in the coming years and design possible coping strategies.…”