This multicenter prospective cohort study will enroll adults who have undergone resection of a primary pulmonary nodule and have residual multiple pulmonary nodules or require routine postoperative pulmonary nodule follow-up. During clinically indicated follow-up visits, a small amount of peripheral venous blood will be collected at the same time as routine blood draws for research CyTOF immune phenotyping and viral imprinting-related serology. The study will not assign participants to treatment, change follow-up schedules, imaging, medication, surgery, or other clinical care. Research laboratory results will not be returned to participants or entered into medical records. The study will describe longitudinal peripheral immune-cell profiles and explore associations among T/B/NK cell phenotypes, T-cell differentiation and senescence/exhaustion markers, viral imprinting markers, and postoperative residual or new pulmonary nodule evolution.
Age 18 years or older, any sex. Primary pulmonary nodule has been surgically resected, with residual multiple pulmonary nodules or a need for pulmonary nodule-related routine postoperative follow-up.
Investigator judges that the participant is unsuitable for additional small-volume blood collection, such as severe anemia, obvious coagulation abnormality, recent severe bleeding, or high risk of severe vasovagal reaction.