Small nodules in the lower lobe of the right lung are small nodules located in the lower lobe of the right lung with a lung diameter of ≤30 mm. The probability of nodule malignancy varies with nodule size, and studies have shown that the overall malignancy of subcentimeter nodules in the lung is low, with a 0%-1% probability of malignancy in multiple lung cancer screening trials for diameters <5 mm, 33%-64% probability of malignancy for diameters 11-20 mm, and >20 mm malignancy The probability of malignancy was 64%-82%. When the probability of malignancy of nodules reaches 10%-60%, further diagnostic tests including PET-CT, puncture biopsy and bronchoscopy are recommended. When the probability of malignancy of lung nodules is higher than 60%-70%, surgical resection is recommended for definite diagnosis and treatment.