Clinical Research Directory

Inclusion Criteria: * patients older than 18 years old with pulmonary nodules (diameter≤3 cm). * pathologically confirmed as lung adenocarcinoma. * without history of other malignancies. * accurate hematocrit within 1 week before contrast enhanced dual energy CT examination. Exclusion Criteria: * with a history of allergy to iodine contrast agents and other reasons who are unable to complete the examination. * without histopathology of invasion stage, such as AAH, AIS, MIA and IAC. * history of chemotherapy, radiotherapy, or other anti-tumor therapy before contrast enhanced dual energy CT. * poor image quality. * contrast enhanced dual energy CT scans ≥ 4 weeks before surgery.