Immune checkpoint inhibitors in cancer patients with COVID-19.

Immune checkpoint inhibitors (ICIs) are widely used to treat a variety of cancers and common infectious diseases with high efficacy. During the coronavirus disease 2019 (COVID-19) pandemic, studies suggested that COVID-19 patients may benefit from ICI immunotherapy. However, clinical studies on the safety and efficacy of ICI in COVID-19 patients are still being conducted. Currently, it is not clear whether cancer patients undergoing ICI immunotherapy should adjust their treatment strategy after infection with SARS-CoV-2 and whether ICI can reduce the viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, reports of patients with different types of tumors infected with SARS-CoV-2 under ICI immunotherapy were classified and sorted, including lung cancer, melanoma, squamous cell carcinoma of the head and neck, and hematologic malignances. The safety and efficacy of ICI in antitumor and anti-SARS-CoV-2 therapies were compared and further discussed to provide more reference materials for the application of ICI treatment. In a word, COVID-19 has changed the ICI treatment strategy for cancer patients indeed, and ICI treatment may be a "double-edged sword" for cancer patients complicated with COVID-19.