Researchers in Italy recently characterized the rate of silent infection with SARS-CoV-2, the coronavirus that causes COVID-19, in patients being treated for cancer, and they reported their findings in the journal The Oncologist.
“To our knowledge, this is the first study on the prevalence and clinical impact of SARS-CoV-2 silent infection in actively treated patients with cancer during the pandemic peak in one of the worst areas of the COVID-19 outbreak,” the researchers stated in their report.
The researchers tested patients receiving anticancer therapy at the Papa Giovanni XXIII Hospital in Bergamo, Italy, throughout the month of April 2020. To be eligible for this study, patients were required to be asymptomatic for COVID-19 or previously mildly symptomatic and not being treated for COVID-19 at the time of study. Patients were tested for immunoglobulin (Ig) G/IgM antibodies against SARS-CoV-2 using a qualitative, membrane-based serological immunoassay. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed on nasopharyngeal swab samples from patients who showed seropositivity using the immunoassay.
From a total of 560 evaluable patients, 31% showed positivity for IgM/IgG antibodies to SARS-CoV-2. Of the seropositive patients who underwent testing by RT-PCR analysis, 58 patients showed a positive result. This gave a rate of silent infection of approximately 10% in this population of patients receiving anticancer treatment.
Among patients who were seropositive for IgM/IgG antibodies to SARS-CoV-2, 37% had been completely asymptomatic, and 63% had experienced mild symptoms during the 8 weeks prior. One patient was reported to have died from COVID-19 during this study’s 8-week follow-up period. A total of 97 patients showing seropositivity with RT-PCR-negativity remained on anticancer treatment; of these patients, 1 went on to develop symptomatic COVID-19 with RT-PCR-positivity.
“Our data indicate the prevalence of the SARS-CoV-2 silent infection is substantial in a consecutive and unselected series of patients with cancer actively treated during the pandemic,” concluded the researchers in their report.
Disclosures: Multiple authors disclosed affiliations with or received funding from the pharmaceutical industry. Please refer to the original article for a full list of disclosures.
Zambelli A, Chiudinelli L, Fotia V, et al. Prevalence and clinical impact of SARS-CoV-2 silent carriers among actively treated patients with cancer during the COVID-19 pandemic. Oncologist. Published online December 23, 2020. doi:10.1002/onco.13654