ABSTRACT
Background: Cancer p represent a high-risk population for severe COVID-19. Cancer-associated immunosuppression may hinder in the development of anti-SARS-CoV-2 antibodies. Methods: Data regarding baseline characteristics (age, cancer type, cancer activity, cancer treatment), COVID-19 infection and anti-SARS-CoV-2 IgG were collected from p with solid tumors who tested positive for COVID-19 (PCR+) between 10th March and 9th December 2020 at Catalan Institute of Oncology. We prospectively assessed anti-SARS-CoV-2 IgG seroprevalence at different timepoints (<2, 2-6, >6 months [m] since first PCR+) and explored factors associated with long-term IgG positivity. Results: Out of 79 registered p, 19 died without IgG testing (all of them <3 months after a PCR+), and 8 refused to participate, leaving 52 tested for IgG. Tested and not-tested p were similar according to baseline characteristics, cancer treatment and COVID-19. At the 1st timepoint, 19/23p were IgG+;at the 2nd, 29/33p were IgG+ and 1 inconclusive;at the 3rd timepoint, 18/22 were IgG+ (median time from PCR + to 3rd timepoint determination was 9.4 m (Interquartile range [IQR]: 8.5-9.7). Importantly, 1 p changed from IgG+ (2nd timepoint) to IgG- (3rd timepoint), and 1 inconclusive result (2nd timepoint) changed to negative (3rd timepoint). Potential factors associated to IgG+ >6 m are shown in the table. [Formula presented] Conclusions: High seroprevalence of anti-SARS-CoV-2 IgG was observed at several timepoints after COVID-19 diagnosis in solid tumor p. P with IgG+ at >6 m were older, and more likely to have required hospitalization and oxygen during prior COVID-19 in comparison to IgG- p >6m, suggesting that infection severity may promote durable immunity. Frequency of active cancer and active chemotherapy at COVID-19 diagnosis were higher among p with IgG- >6m, suggesting deeper immunosupression. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: E. Felip: Financial Interests, Personal, Other: Pfizer;Financial Interests, Personal, Other: Lilly;Financial Interests, Personal, Other: Eisai;Financial Interests, Personal, Other: Novartis;Financial Interests, Personal, Sponsor/Funding: Pfizer. M. Romeo Marin: Financial Interests, Personal, Advisory Board: MSD;Financial Interests, Personal, Advisory Board: MSK;Financial Interests, Personal and Institutional, Other: MSD;Financial Interests, Personal and Institutional, Principal Investigator: AZ;Financial Interests, Personal and Institutional, Principal Investigator: GSK Tesaro;Financial Interests, Personal and Institutional, Principal Investigator: Merck. All other authors have declared no conflicts of interest.
ABSTRACT
Background: Cancer patients (pts) represent a high-risk population for severe COVID-19. Cancer-associated immunosuppression may hinder in the development of anti-SARS-CoV-2 antibodies. Methods: Data regarding baseline characteristics, COVID-19 and anti-SARS-Cov2 IgG were collected from cancer pts (solid tumors) who tested positive for COVID-19 (PCR+) between March and April 2020 at Catalan Institute of Oncology. We prospectively assessed anti-SARS-Cov2 IgG seroprevalence at 3 and 9 months post infection and explored clinico-pathologic factors associated with IgG positivity. We explored the impact of potential factors influencing antibody production at >9 months. Results: Of 49 pts registered between 10 March-26 April 2020, 21 died <3 months after the infection and 5 pts refused to participate, leaving 23 eligible pts for IgG testing. With respect to those not tested, IgG tested cohort was younger (median age: 64.0 vs 72.9 years, p = 0.001) and presented oncologic remission in 68.2% of cases (vs 34.6%, p = 0.043) at COVID-19 diagnosis. Median time from PCR+ to first and second IgG determination was 3.2 months (Interquartile range [IQR]: 2.9-4.1) and 9.5 months (IQR: 8.8-9.8), respectively. Out of 23 pts, 15 had both determinations and 8 had only one (3 in the first time point, 5 in the second one). We identified 16/18 pts IgG+ (88.9%) at 3 months and 17/20 pts IgG+ (85%) at 9 months. One IgG+ pt became IgG-at the second determination, one was IgG-at both timepoints, and one had an inconclusive result at the first but negative at the second timepoint. Key characteristics of patients by IgG result 9 months after COVID-19 diagnosis are shown in the table. Conclusions: We describe a high seroprevalence of anti-SARS-CoV-2 IgG at 3 and 9 months after COVID-19 diagnosis in solid tumour patients, irrespective of anti-cancer therapy exposure. Pts who were IgG+ at 9 months were older, and more likely to have required oxygen during prior COVID-19 in comparison to IgG-pts suggesting that infection severity may promote durable immunity. Frequency of early stage cancers was higher among IgG+ pts, suggesting less cancerrelated immunosupression. Older (>70 years) and advanced cancer pts were underrepresented in this series, warranting confirmation of these preliminary results in a larger cohort.