The relationship between cancer and coronavirus disease 2019 (COVID‐19) infection and severity remains poorly understood. We conducted a population‐based cohort study between 1 March and 6 May 2020 describing the associations between cancer and risk of COVID‐19 diagnosis, hospitalisation and COVID‐19‐related death. Data were obtained from the Information System for Research in Primary Care (SIDIAP) database, including primary care electronic health records from ~80% of the population in Catalonia, Spain. Cancer was defined as any primary invasive malignancy excluding non‐melanoma skin cancer. We estimated adjusted hazard ratios (aHRs) for the risk of COVID‐19 (outpatient) clinical diagnosis, hospitalisation (with or without a prior COVID‐19 diagnosis) and COVID‐19‐related death using Cox proportional hazard regressions. Models were estimated for the overall cancer population and by years since cancer diagnosis (
What's new? Studies addressing associations between cancer and severity of coronavirus disease 2019 (COVID‐19) have focused primarily on hospitalized patients. Findings have been inconsistent, however, owing to varying cancer criteria, lack of representative samples, and other factors. Here, the natural history of COVID‐19 in cancer patients during the first wave of the pandemic in 2020 in Spain was investigated in a large, representative cohort with a heterogenous cancer population. Patients with cancer were at increased risk of severe COVID‐19. Risk was notably high among those over age 70 and those with recent cancer diagnosis, hematological cancer, or lung and bladder cancer.