Assessment System of Sarcopenia in Lung Cancer Patients

1. To explore the diagnostic value of musculoskeletal cross-modal imaging assessment system of ultrasound combined with abdominal CT/MRI for sarcopenia in patients with lung cancer. 2. To explore the value of musculoskeletal cross-modal imaging assessment system of ultrasound combined with abdominal CT/MRI in evaluating the prognosis and the effect of nutritional support in patients with lung cancer during perioperative period. 3. To explore the value of musculoskeletal cross-modal imaging assessment system of ultrasound combined with abdominal CT/MRI in evaluating the long-term prognosis of patients with lung cancer.