To the Editor In their article in JAMA Oncology, Yu et al1 reported an increased incidence of coronavirus disease 2019 (COVID-19) in patients with cancer compared with the general population of Wuhan, China. The authors hypothesized this relation to be secondary to an immunocompromised state in patients with cancer. Contrary to hematologic cancers, the link between solid cancers and risk of infection is unclear. It is this author’s opinion that this report provides no support for this connection.
The authors compared the total number of cases with the number of patients with cancer diagnosed with COVID-19. This approach is hampered by an insufficient understanding of the true number of cases. One study estimated that up to 50% of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in Wuhan might be asymptomatic.2 Considering this degree of uncertainty and the low number of affected patients with cancer in this study, there is insufficient certainty to reliably conclude an increased incidence in patients with cancer.
The results might also have been influenced by confounding factors. Most patients were treated for non–small cell lung cancer (7 of 12 patients). Patient history of cigarette smoking was not provided. Smoking leads to structural and immunologic changes to the airway, leading to more frequent and more severe viral infections.3 It also leads to upregulation of ACE2,4 the hypothesized protein used by SARS-CoV-2 for cellular entry. In one COVID-19 study,5 14.5% of patients were current or former smokers. In the group of patients that reached a study end point (intensive care unit admission, mechanical ventilation, or death), this percentage rose to 33.4%.5 Only 0.9% of 1099 patients had cancer, with just 1 patient reaching the study’s end point. These results suggest that smoking increases the risk of severe disease more than the presence of cancer and could have been a confounding factor.
Most patients were in a phase of their disease where frequent hospital visits are expected. Receiving cancer treatment (6 patients) or supportive care (4 patients) and having a recent diagnosis of malignant neoplasm (1 patient) are reasons for frequent contacts with health care providers. As the authors state, considering the reports of hospital-acquired infections in this COVID-19 pandemic, frequent hospital visits are another potential confounder.
Although this study provides no support for increased susceptibility for SARS-CoV-2 infection in patients with cancer based on cancer-related immunosuppression, it is important to consider the fragility of patients with cancer during the COVID-19 pandemic. Considering the risk of nosocomial infections, delay of necessary treatments, and uncertainty regarding health care availability, SARS-CoV-2 undoubtedly poses a great risk for patients with cancer.
Corresponding Author: Tim Johannes Adrianus Dekker, PhD, Department of Internal Medicine, Haaglanden Medisch Centrum, The Hague, The Netherlands (t.j.a.dekker@gmail.com).
Published Online: July 2, 2020. doi:10.1001/jamaoncol.2020.2580
Conflict of Interest Disclosures: None reported.
4.Hung
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WY, Hsieh
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