Seroconversion in patients with cancer and oncology healthcare workers infected by SARS-CoV-2

BACKGROUND: Patients with cancer have high risk for severe complications and poor outcome to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related disease (coronavirus disease 2019 [COVID-19]). Almost all subjects with COVID-19 develop anti-SARS-CoV-2 immunoglobulin-G (IgG) within three weeks after infection. No data are available on the seroconversion rates of cancer patients and COVID-19.MATERIAL AND METHODS: We conducted a multicenter, observational, prospective study that enrolled: 1) patients and oncology health professionals with SARS-CoV-2 infection confirmed by real time polymerase chain reaction (RT-PCR) assays on nasal/pharyngeal swab specimens; 2) patients and oncology health professionals with clinical or radiological suspicious of infection by SARS-CoV-2; and 3) patients with cancer who are considered at high risk for infection and eligible for active therapy and/or major surgery. All enrolled subjects were tested with the 2019-nCoV IgG/IgM Rapid Test Cassette, which is a qualitative membrane-based immunoassay for the detection of IgG and IgM antibodies to SARS-CoV-2. The aim of the study was to evaluate anti-SARS-CoV-2 seroconversion rate in patients with cancer and oncology healthcare professionals with confirmed or clinically suspected COVID-19.RESULTS: From March 30 to May 11, 2020, 166 subjects were enrolled in the study. Among them, cancer patients and health workers were 61 (36.7%) and 105 (63.3%), respectively. Overall, 86 subjects (51.8%) had confirmed SARS-CoV-2 diagnosis by RT-PCR testing on nasopharyngeal swab specimen, while 60 (36.2%) had a clinical suspicious of COVID-19. Median time between symptom onset (for cases not confirmed by RT-PCR) or RT-PCR confirmation to serum antibody test was 17 days (interquartile range, 26). In the population with confirmed RT-PCR, 83.8% was IgG positive. No difference in IgG positivity was observed between cancer patients and health workers (87.9% vs 80.5%; P = 0.39).CONCLUSIONS: Our data indicate that SARS-CoV-2-specific IgG antibody detection do not differ between cancer patients and healthy subjects.