SARS-CoV-2 testing for asymptomatic adult cancer patients before initiating systemic treatments: a systematic review

Abstract

Introduction Cancer patients may have a higher risk of severe events and unfavourable outcomes in the setting of COVID-19. This review addresses the question of whether to test asymptomatic cancer patients before initiating systemic cancer treatments. Methods This systematic review was conducted based on the PRISMA framework. Pubmed, Embase, Web of Science and Cochrane Central Register of Controlled Trials were systematically searched, as well as guidelines from international institutions involved in cancer care and COVID-19 research. Studies published in English, from 1 December 2019 to 27 May 2020 were considered eligible. We included studies which mentioned testing strategies for SARS-CoV-2 of asymptomatic cancer patients before starting immunosuppressive treatments. Results We identified 1,163 studies and 4 guidelines through the literature search. A total of 18 articles were considered eligible and were included in the final analysis. Two articles were cohort studies, and the remaining were expert consensuses and published guidelines. The most common recommendation among the studies in this systematic review was to test asymptomatic patients for SARS-CoV-2 prior to treatment. Conclusion There is a lack of studies which directly address COVID-19 testing of asymptomatic patients before treatment. Our systematic review showed that most of the published data favours routine test for SARS-CoV-2 before initiating systemic treatment but failed to identify a good level of evidence to support these recommendations. Based upon this review, we proposed local recommendations at our centre. Each institution should consider the pros and cons of testing asymptomatic patients, evaluating accessibility to testing resources and local epidemiology.

Natural immunity to SARS-CoV-2 and breakthrough infections in vaccinated and unvaccinated patients with cancer

“…Another factor potentially involved in defining the incidence of reinfections in patients with cancer is the deployment of periodic asymptomatic SARS-CoV-2 screening, which was largely recommended in the years 2020/2021 ahead of anticancer therapy or other diagnostic/therapeutic procedures [24,25], although clear evidence of its clinical utility is still lacking [26][27][28].…”

ESCMID guidelines on testing for SARS-CoV-2 in asymptomatic individuals to prevent transmission in the health care setting

“…The latter point, in conjunction with the purported lower sensitivity of rapid antigen tests, supports the CDC recommendation for at least weekly RT-PCR testing when there is high risk of transmission. Evidence summary: The evidence was extracted from the ECDC technical report on contact tracing, the WHO guidance on infection prevention in long-term care facilities, and two systematic review addressing universal screening (3,4,38,39). No systematic review specifically assessing the effectiveness of testing versus no testing of asymptomatic HCWs after high-risk exposure was retrieved from the initial search.…”

“…Two systematic reviews have addressed the utility of mass testing in special settings such as cancer institutions (39) and LTCFs (38), underlying the importance of testing patients and healthcare workers during outbreak situations independently from the risk of the exposure. This strategy is recommended in presence of nosocomial transmission, either occurring in a hospital ward or in a LTCF, by the WHO and the ECDC with the aim of detecting ongoing asymptomatic infections among patients or HCWs.…”

Universal Screening of Patients with Cancer for COVID-19: Results from an Observational, Retrospective Cohort Study in Kerala, India

“…8 International agencies such as the American Society of Clinical Oncology (ASCO), 9 European Society of Medical Oncology (ESMO), 10 Infectious Disease Society of America (IDSA), 11 and National Comprehensive Cancer Network (NCCN) 12 recommend screening every patient undergoing chemotherapy to identify casualties early and isolate them to prevent infection to other patients as well as to health care workers. 13 Following the COVID-19 infection, an asymptomatic period lasts 2 weeks, during which viral transmission occurs. 14 15 The percentage of asymptomatic infection ranges from 20 to 31%, and such asymptomatic persons can transmit the infection to others.…”