© 2021, Springer Science+Business Media, LLC, part of Springer Nature.During the COVID-19 pandemic, it is important to assure the safety and management of cancer patients. Despite preliminary studies revealed that patients with cancer are more susceptible to infection and have poorer prognosis than other infected patients without cancer, mortality from COVID-19 in cancer patients appears to be principally driven by age, gender, and comorbidities. So, we have some comments about the pathogenesis attributed to the COVID-19 disease and cancer relationship and determination of subgroups in this and oncoming studies. Variable effects of anticancer treatments on the patient's immune system are yet to be elucidated. On the other hand, the effect of SARS-CoV-2 virus on tumor microenvironment or immune responses in cancer is not yet fully proven. Very recently, Challenor and her colleague reported a case with classical Hodgkin lymphoma with stage IIIs disease, which went into remission without corticosteroid or immunochemotherapy. They assumed that the putative mechanisms of action include cross-reactivity of pathogen-specific T cells with tumor antigens and natural killer cell activation by inflammatory cytokines produced in response to infection. During the course of COVID-19 disease, immune checkpoint blockade effect might be induced naturally.