COVID-19 Incidence and Mortality in Patients Operated on for Breast Cancer. Comparison with the General Population

Breast Cancer (BC) remains the most diagnosed malignancy and the most common cause of cancer-related mortality in women worldwide. Covid-19 mortality in BC patients has been linked to comorbid conditions rather than to cancer treatment itself, although this was not confirmed by a meta-analysis. Also, during Covid-19 outbreaks, a great deal of health care resources is reassigned to critical Covid-19 patients.

During 5 consecutive trimesters (from 1/12/2020 to 31/3/2021) 2511 BC patients older than 20 years from our institution were surveyed. 1043 of them had received a Covid test and these made our study group, which was conveniently compared with the Covid-19 tested background feminine Catalan population.

13.1% of our patients presented with a positive Covid-19 test, whereas confirmed COVID-19 infection amounted to 7.1% of the feminine Catalan tested population. The COVID-19-specific mortality rate was 11.7% (16/137) in the study group, which compares with a 4.7% rate for the overall population. Most deaths occurred in patients over 70.

Three clinical factors were significantly associated with Covid-19 mortality in BC, namely lack of hormone therapy, distant metastases, and BC dwelling in nursing homes. BC patients are at a higher risk of Covid-19 infection and mortality in comparison with the reference group without BC.