Prevalence of COVID-19 Infection in Asymptomatic Cancer Patients in a District With High Prevalence of SARS-CoV-2 in Italy

Background Cancer patients are presumed a frail group at high risk to contract coronavirus disease (COVID-19). The aim of this study was to investigate the prevalence of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection in asymptomatic cancer patients attending the outpatient clinic of a general hospital in a region with a high prevalence of SARS-CoV-2 infection (North Italy, first wave). Methods We retrospectively analyzed data of consecutive cancer patients attending the outpatient clinic of the oncology unit, General Hospital of Piacenza. All the patients having underlying cancer, without clinical suspicion of COVID-19, attending the outpatient clinic underwent nasopharyngeal swabs, from April 3, 2020 to June 3, 2020 and were included in this study. Results In a two-month period, 260 consecutive, asymptomatic (for COVID-19) cancer patients were tested for COVID-19. There were 160 women and 100 men; 218 patients were under active anticancer treatment, 32 in the diagnostic/staging phase waiting for treatment, and 10 treated with supportive care only. Ten of the 260 patients (3.85%) showed COVID-19 positivity. All but one (treated with hormone therapy) of the COVID-19 positive patients delayed anticancer treatment. The mean delay of anticancer treatment was 45.86±27.66 days (range 21-87 days), and the mean time for viral clearance was 25.7±22.68 days (range 7-79 days). All the 10 patients with COVID-19 and cancer overcame the infection, and treated patients could restart anticancer treatment. Conclusion Our data indicate a high prevalence of COVID-19 in cancer patients in an area with a high prevalence of SARS-CoV-2 infection. Routine COVID-19 testing of cancer patients when asymptomatic allowed an early detection, isolation, and treatment, avoiding viral spread among other frail patients and among medical/nurse staff.