Identifying the patients at higher risk for poor outcomes after radiotherapy (RT) during coronavirus disease 19 (COVID-19) era is an unmet clinical need.

The Ovid MEDLINE, Ovid Embase, Clarivate Analytics Web of Science, PubMed and Wiley-Blackwell Cochrane Library databases were searched. Eligible studies were required to address the outcomes of cancer patients who underwent RT during the COVID-19 era. The primary outcome was early mortality, while secondary outcomes included length of hospital stay, hospital admission, intensive care unit (ICU) admission and use of mechanical ventilation. Pooled event rates were calculated, and meta-regression and ‘leave-one-out’ sensitivity analyses were performed.

Twelve eligible studies were included out of 928. The prevalence of early mortality after COVID-19 infection was 21·0%. The prevalence of hospital admission, ICU admission and mechanical ventilation was 78·1, 15·4 and 20·0%, respectively. Meta-regression showed that older age was significantly and positively associated with early mortality (β = 0·0765 ± 0·0349, p = 0·0284), while breast cancer was negatively associated with early mortality (β = −1·2754 ± 0·6373, p = 0·0454).

Older age adversely impacts the early mortality rate in cancer patients during COVID-19 era. The risks of interruption/delay of cancer treatment should be weighed against the risk of increased morbidity and mortality from the infection. A global registry is needed to establish international oncologic guidelines during the COVID-19 era.