Psychological Stress in Breast Cancer Patients during the Course of a Pandemic Disease: Before and after the Availability of Vaccines

Introduction: The COVID-19 pandemic led to restrictions in public life and significantly impaired treatment processes for oncological treatments. In this trial, we compared breast cancer (BC) patients' psychological stress before and after the availability of vaccines against COVID-19. Methods: Patients that received preoperative, postoperative, or palliative treatment for their BC diagnosis during the COVID-19 pandemic between 2020 and 2022 were included. Cohort 1 comprised patients prior to the availability of vaccines and Cohort 2 comprised patients from 2021 when vaccines against COVID-19 were available. We evaluated differences in mental state, influencing factors on quality of life (QoL) and factors causing distress during their BC treatments by several questionnaires. Results: When comparing 82 BC patients (Cohort 1) with 91 patients (Cohort 2), we found quite similar psychosocial parameters and secondary diagnoses. Eighty-five patients (93.41%) in Cohort 2 had been vaccinated. The cohorts did not differ regarding their concern toward the pandemic. We found that stress caused by insecurity (19.00 [11.00-26.00] in Cohort 1 vs. 16.00 [10.00-21.00] in Cohort 2 [p = 0.050]) and stress by loss (11.00 [9.00-16.00] in Cohort 1 vs. 10.00 [7.00-13.00] in Cohort 2 [p = 0.047]) decreased in Cohort 2, while all other parameters of distress did not show differences. Patients in Cohort 2 felt moderate burden due to restriction of accompanying persons and visits during hospitalization without corresponding changes to the QoL. In contrast, their own vaccination and the vaccination of their relatives showed positive impact on their QoL. Vaccination appeared to only minimally affect everyday behavior. Conclusion: This trial shows positive psychological vaccination effects with only a limited influence on the distress of BC patients.