ABSTRACT
BACKGROUND/AIM: The severity and associated mortality of coronavirus disease 2019 (COVID-19) are higher in patients with thoracic cancer than in healthy populations and those with other cancer types. Here, we investigated real-world data on the incidence of COVID-19 and false-negative cases using severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) real-time reverse-transcription polymerase chain reaction (rRT-PCR) testing in patients with thoracic cancer. PATIENTS AND METHODS: We retrospectively reviewed patients with advanced thoracic cancer at the National Cancer Center Hospital between March 2020-May 2021. Blood samples were collected and evaluated for IgM and IgG antibodies specific for nucleocapsid (N) and spike (S) protein SARS-CoV-2 before and after rRT-PCR testing. False-negative cases were assessed based on anti-SARS-CoV-2 antibody levels before and after rRT-PCR testing. RESULTS: A total of 2,107 patients with thoracic cancer were identified between March 2020 and May 2021, 7 (0.3%) of whom developed COVID-19. Among the 218 patients who underwent at least one rRT-PCR test because of suspected COVID-19 symptoms or as a screening test at our institute, the most common diagnosis was non-COVID-19 pneumonia (34.4%), followed by tumor fever (30.7%). Furthermore, of the 218 patients, 120 paired serum samples before and after rRT-PCR testing were available. Seroconversion was identified in all three patients with positive SARS-CoV-2 rRT-PCR results but was only observed in 1 out of the 117 patients who tested negative; the rate of false-negative cases was low (0.9%). CONCLUSION: COVID-19 incidence among patients with advanced thoracic cancer was low during the early phase of the pandemic in Japan.