Cancer associates with risk and severe events of COVID ‐19: A systematic review and meta‐analysis

Evidence is mounting to indicate that cancer patients may have more likelihood of having coronavirus disease 2019 (COVID‐19) but lack consistency. A robust estimate is urgently needed to convey appropriate information to the society and the public, in the time of ongoing COVID‐19 pandemic. We performed a systematic review and meta‐analysis through a comprehensive literature search in major databases in English and Chinese, and two investigators conducted publication selection and data extraction independently. A meta‐analysis was used to obtain estimates of pooled prevalence of cancer in patients with COVID‐19 and determine the association of cancer with severe events, after assessment of potential heterogeneity, publication bias, and correction for the estimates when necessary. Total 38 studies comprising 7,094 patients with COVID‐9 were included; the pooled prevalence of cancer was estimated at 2.3% (95% confidence limit[CL] [0.018, 0.029]; p