Clinical Research Directory

Inclusion Criteria: \- 1. At least one persistent indeterminate pulmonary nodule measuring 6 to 30 mm on the latest clinically obtained CT; solid, part-solid, and pure ground-glass nodules are eligible. 2. Two CT examinations in total are already available: the latest within 30 days before randomization and an earlier examination 3 to 24 months before it. Both meet the frozen image-quality requirements for longitudinal comparison. 3. The current decision between continued surveillance and further investigation remains unresolved, with no mandatory urgent procedure or committed definitive treatment before randomization. 4\. The patient is potentially eligible for curative treatment if cancer is diagnosed, with an estimated life expectancy of at least five years independent of the study nodule. 5. Written informed consent and willingness to permit record retrieval and five-year contact. Exclusion Criteria: \- 1.Definitive diagnosis or previous treatment of the target nodule; overt metastatic disease, suspicious adenopathy requiring urgent work-up, or another indication making delayed evaluation inappropriate. 2.Active malignancy or cancer treatment within the preceding five years, except definitively treated nonmelanoma skin cancer or in situ cervical cancer. 3\. Clinically important immunocompromise or active pulmonary infection requiring a separate diagnostic pathway. 4. Current participation in an organized lung-cancer screening program with a mandated management pathway incompatible with this trial. 5. CT quality or acquisition differences prevent valid longitudinal evaluation; a clearly benign lesion does not require a diagnostic management decision. 6. Known pregnancy; a conflicting interventional trial; prior randomization in this study; or consent cannot be obtained.