Negative Impact of COVID-19 Associated Health System Shutdown on Patients Diagnosed With Colorectal Cancer: A Retrospective Study From a Large Tertiary Center in Ontario, Canada

  1. Catherine L Forse
  2. Stephanie Petkiewicz
  3. Iris Teo
  4. Bibianna Purgina
  5. Kristina-Ana Klaric
  6. Tim Ramsay
  7. Jason K Wasserman

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Abstract

Background

In March 2020, a directive to halt all elective and non-urgent procedures was issued in Ontario, Canada because of COVID-19. The directive caused a temporary slowdown of screening programs including surveillance colonoscopies for colorectal cancer (CRC). Our goal was to determine if there was a difference in patient and tumour characteristics between CRC patients treated surgically prior to the COVID-19 directive compared to CRC patients treated after the slowdown.

Methods

CRC resections collected within the Champlain catchment area of eastern Ontario in the 6 months prior to COVID-19 (August 1, 2019–January 31, 2020) were compared to CRC resections collected in the 6 months post-COVID-19 slowdown (August 1, 2020–January 31, 2021). Clinical (e.g., gender, patient age, tumour site, and clinical presentation) and pathological (tumour size, tumour stage, nodal stage, and lymphovascular invasion) features were evaluated using chi-square tests, T-tests, and Mann–Whitney tests where appropriate.

Results

Three hundred and thirty-eight CRC specimens were identified (173 pre-COVID-19, 165 post-COVID-19 slowdown). CRC patients treated surgically post-COVID-19 slowdown had larger tumours (44 mm vs. 35 mm; P = 0.0048) and were more likely to have presented emergently (24% vs. 10%; P < 0.001). Although there was a trend towards higher tumour stage, nodal stage, and clinical stage, these differences did not reach statistical significance. Other demographic and pathologic variables including patient gender, age, and tumour site were similar between the two cohorts.

Interpretation

The COVID-19 slowdown resulted in a shift in the severity of disease experienced by CRC patients in Ontario. Pandemic planning in the future should consider the long-term consequences to cancer diagnosis and management.

Article activity feed

  1. Version published to 10.1093/jcag/gwab044
  2. ScreenIT

    SciScore for 10.1101/2021.07.30.21261400: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    EthicsIRB: Ethics approval: This study was approved by the Ottawa Health Science Network Research Ethics Board (20200331-01H).
    Sex as a biological variablenot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.

    Table 2: Resources

    Software and Algorithms
    SentencesResources
    Data were analysed using the Statistical Package for Social Sciences (SPSS) (IBM SPSS Statistics for Windows, version 25.0 (IBM Corp.).
    SPSS
    suggested: (SPSS, RRID:SCR_002865)

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    An important limitation of the current study is that, while we were able to show significant differences between the post-slowdown and pre-slowdown cohorts, we cannot identify a specific cause. One possible explanation is that the lack of screening procedures during the slowdown period resulted in more cancers going undetected at an earlier stage and that this led to a disproportionate number of advanced cancers in the post-slowdown cohort. This explanation would apply to those patients who would have normally undergone a screening procedure but were delayed/cancelled due to the slowdown. Another possible explanation is that some people may have been reluctant to seek medical attention. This may have been out of personal fear of COVID-19 or out of respect for government messaging to stay at home. Thus, some people may have discounted early warning signs and only presented to hospital once they had developed “alarm” symptoms (e.g., persistent abdominal pain). Unfortunately, both explanations involve system failures at a population level. In summary, our findings demonstrate that health care policies put in place at the beginning of the COVID-19 pandemic in Ontario, Canada were ultimately associated with more advanced disease in patients diagnosed with CRC. Worsening cancer burden not only increases patient morbidity and mortality, but also has long-term social and economic effects on oncological care. Governments and health authorities should consider these results when creati...

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a protocol registration statement.

    Results from scite Reference Check: We found no unreliable references.

    About SciScore

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  3. Version published to 10.1101/2021.07.30.21261400v1 on medRxiv