The impact of Omicron pandemic and COVID-19 vaccination on the pancreatic adenocarcinoma patients.

ABSTRACT

Background: The coronavirus disease 2019 (COVID-19) pandemic resulted in enormous medical and economic burden worldwide during the past 3 years. The vaccination was deemed the effective option to prevent the severe symptoms, and especially recommended among cancer patients. Shanghai experienced the first lockdown during the recent Omicron pandemic since 2019. How patients with pancreatic adenocarcinoma (PAC) suffered from the pandemic and how vaccination influenced their oncological outcomes were unexplored yet. Method: The retrospective study was carried out in a high-volume referral center including 1157 consecutively enrolled patients with PAC experiencing the COVID-19 pandemic. The primary outcome was the overall survival (OS). Results: Limited postoperative patients (9.21%) received the vaccination. The lockdown in Shanghai (April to May, 2022) was not observed impacting the survival prognoses of patients with PAC. Though vaccination was not significantly associated with OS itself (adjusted hazard ratio (aHR) 2.032 [0.940-4.391], p = 0.071), it was discovered to synergistically improve the chemotherapy effect in the multivariate analyses (interaction p = 0.023). Conclusion: The vaccination itself did not influence the survival prognoses of patients with PAC. A potential positive interaction was observed between chemotherapy and vaccination despite the limited follow-up time. The postoperative patients should consider the vaccination more. The patients with PAC did not suffer worse prognostic outcomes from the strict sanitary policy during the wave of COVID-19 pandemic in Shanghai.