Effect of cancer on outcome of COVID-19 patients: a systematic review and meta-analysis of studies of unvaccinated patients

Abstract

Background: Since the beginning of the SARS-Cov2 pandemic, cancer patients affected by COVID-19 have been reported to experience poor prognosis; however, a detailed quantification of the effect of cancer on outcome of unvaccinated COVID-19 patients has not been performed.

Methods: To carry out a systematic review of the studies comparing the outcome of unvaccinated COVID-19 patients with and without cancer, a search string was devised which was used to identify relevant publications in PubMed up to December 31, 2020. We selected three outcomes: mortality, access to ICU, and COVID-19 severity or hospitalization. We considered results for all cancers combined as well as for specific cancers. We conducted random-effects meta-analyses of the results, overall and after stratification by region. We also performed sensitivity analyses according to quality score and assessed publication bias.

Results: For all cancer combined, the pooled odds ratio (OR) for mortality was 2.32 (95% confidence interval [CI] 1.82-2.94, I2 for heterogeneity 90.1%, 24 studies), that for ICU admission was 2.39 (95% CI 1.90-3.02, I20.0%, 5 studies), that for disease severity or hospitalization was 2.08 (95% CI 1.60-2.72, I2 92.1%, 15 studies). The pooled mortality OR for hematologic neoplasms was 2.14 (95% CI 1.87-2.44, I2 20.8%,8 studies). Data were insufficient to perform a meta-analysis for other cancers. In the mortality meta-analysis for all cancers, the pooled OR was higher for studies conducted in Asia than studies conducted in Europe or North America. There was no evidence of publication bias.

Conclusions: Our meta-analysis indicates a two-fold increased risk of adverse outcomes (mortality, ICU admission and severity of COVID-19) in unvaccinated COVID-19 patients with cancer compared to COVID-19 patients without cancer. These results should be compared with studies conducted in vaccinated patients; nonetheless, they argue for special effort to prevent SARS-Cov2 infection in patients with cancer.

Funding: No external funding was obtained.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting file.Dataset has been deposited on Dryad (doi:10.5061/dryad.00000004q)

The following data sets were generated

Article and author information

Author details

  1. Giulia Di Felice

    Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
    Competing interests
    The authors declare that no competing interests exist.
  2. Giovanni Visci

    Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
    For correspondence
    giovanni.visci6@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2246-2321
  3. Federica Teglia

    Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3188-1632
  4. Marco Angelini

    Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
    Competing interests
    The authors declare that no competing interests exist.
  5. Paolo Boffetta

    Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
    For correspondence
    paolo.boffetta@unibo.it
    Competing interests
    The authors declare that no competing interests exist.

Funding

The authors declare that there was no funding for this work.

Ethics

Human subjects: a) All methods were carried out in accordance with relevant guidelines and regulations.b) The study was considered exempt and the informed consent was not deemed necessary given the nature of the study

Copyright

© 2022, Di Felice et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Giulia Di Felice
  2. Giovanni Visci
  3. Federica Teglia
  4. Marco Angelini
  5. Paolo Boffetta
(2022)
Effect of cancer on outcome of COVID-19 patients: a systematic review and meta-analysis of studies of unvaccinated patients
eLife 11:e74634.
https://doi.org/10.7554/eLife.74634

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https://doi.org/10.7554/eLife.74634