International disruptions to cancer diagnosis and stage at presentation during the COVID-19 pandemic in 2020: an International Cancer Benchmarking Partnership (ICBP) population-based study
Menée à partir de données internationales portant sur 2,6 millions de patients atteints d'un cancer diagnostiqué entre 2015 et 2020, cette étude internationale examine l'impact de la pandémie liée à la COVID-19 sur les diagnostics et la stadification des cancers en 2020
Background: The COVID-19 pandemic had an impact on cancer services globally. There is a crucial need to understand how the incidence and stage of major cancer types were affected internationally. We aimed to assess these metrics in seven countries within the International Cancer Benchmarking Partnership.
Methods: This population-based study used data on 2·6 million patients diagnosed with primary cancers of the colon, rectum, lung, prostate, female breast, ovary, and melanoma of the skin, between Jan 1, 2015, and Dec 31, 2020. Data were collected from cancer registries in 18 jurisdictions from seven countries participating in the International Cancer Benchmarking Partnership; Australia, Canada, Denmark, Ireland, New Zealand, Norway, and the UK. The main outcomes of monthly cases and age-standardised incidence rates by site during the pandemic (April 1 to Dec 31, 2020) were compared with predictions for the same year based on pre-pandemic trends (Jan 1, 2015, to Dec 31, 2019).
Findings: Between April 1, and Dec 31, 2020, 55 713 (16%) of 347 666 expected cases were predicted to be missing, with the largest deficits seen for prostate cancer (24%), female breast cancer (18%), and melanoma (18%), and the smallest deficits seen for ovarian (4%) and lung cancer (8%). The largest difference between observed and predicted incidence rates for prostate cancer was seen in the UK (164·9 per 100 000 person-years predicted vs 101·4 per 100 000 person-years observed) and the smallest difference seen in Norway (164·1 vs 168·4). Reductions in incidence were greatest from April 1, to July 31, versus from Aug 1, to Dec 31, in 2020. The percentage deficits between observed and predicted cases were 54% (UK) and 36% (Ireland) for prostate cancer, 40% (UK) and 34% (Ireland) for breast cancer, and 40% (UK) and 35% (Canada) for melanoma.
Interpretation: The pandemic's greatest impact was during the first few months of societal lockdowns in 2020 when barriers in access to health care were greatest. Further research is needed to understand whether patients with a missed diagnosis were diagnosed at a later date and if they presented at a later stage.
The Lancet Oncology , résumé, 2026