Safety of anti-SARS-CoV-2 messenger RNA vaccine in lung cancer patients undergoing anticancer chemotherapy: A multicenter, prospective, observational, patient-reported outcome study

Background: COVID-19 incidence is high in patients with cancer. The fatality rate was high for the Delta variant, necessitating infection prevention by vaccination. This study evaluated the safety of a SARS-CoV-2 vaccine in patients with advanced lung cancer receiving anticancer therapy. Methods: We prospectively enrolled patients receiving anticancer drugs for advanced lung cancer and planning SARS-CoV-2 vaccination. Early side effects within 7 days of vaccination were evaluated using patient-reported outcome (PRO) surveys. Chi-square test and multivariate logistic regression analyses were used. Results: Post-vaccination PROs were collected from 406 patients (252 were males). The mean age was 72 years. Treatment at the time of initial vaccination included chemotherapy, immune checkpoint inhibitors (ICI), a combination of chemotherapy and ICI, targeted therapy including tyrosine kinase inhibitors, and others in 115, 93, 45, 147, and six cases, respectively. The vaccines administered were BNT162b2 and mRNA273 in 361 and three cases, respectively and unknown in 42 cases. A total of 16.1% of patients developed fever (38°C) after the second mRNA vaccination (95% confidence interval: 12.6%–20.1%). This rate is comparable to data previously reported in 120 patients and slightly higher than that of healthy participants of the BNT162b2 study. Patients receiving treatment with cytotoxic anticancer agents were more likely to have high fever. Multivariate analysis showed no correlation between fever frequency and patient background. No serious initial adverse events due to vaccination were observed. Conclusions: Anti-SARS-CoV-2 mRNA vaccination is safe; however, post-vaccination fever is more common in patients undergoing lung cancer treatment than in healthy individuals.