Inclusion Criteria:  Pulmonary nodule/lung cancer patients confirmed by CT or pathological examination, who have been vaccinated against the SARS-CoV-2 Pulmonary nodule/lung cancer patients confirmed by CT or pathological examination, who are not vaccinated against the SARS-CoV-2 Healthy people who have been vaccinated against the SARS-CoV-2  Exclusion Criteria:  Multiple malignancy in other parts of body; Infected with SARS-CoV-2 virus currently or in the past; Refuse to participate in this study.