Radical Resection With Contralateral Lymph Node Dissection for Clinical N3 NSCLC

Inclusion Criteria: * Histologically confirmed primary non-small cell lung cancer (NSCLC): The diagnosis must be confirmed through pathological examination, and the patient must meet one of the following histological types: adenocarcinoma, squamous cell carcinoma, or large cell carcinoma. * PET-CT indicating contralateral mediastinal lymph node metastasis, N3 stage: Patients must have lung cancer classified as stage N3 based on positron emission tomography (PET) scans, with evidence of contralateral mediastinal lymph node involvement. * Age range: Patients must be aged between 18 and 75 years. * Good cardiopulmonary function:Preoperative evaluation must show no significant cardiovascular conditions (e.g., heart failure, severe coronary artery disease) or severe respiratory diseases (e.g., chronic obstructive pulmonary disease), and the patient must have good heart function (LVEF ≥ 45%), with the ability to tolerate surgery.Preoperative pulmonary function assessment must meet the surgical criteria, with forced expiratory volume in 1 second (FEV1) ≥ 50% of predicted value. * Resectable tumor: Based on imaging studies (such as CT or MRI) and assessment by thoracic surgeons, the patient must be deemed suitable for surgical resection and planned for primary tumor resection combined with bilateral lymph node dissection. * No distant metastasis: Full-body imaging (such as CT or PET-CT) must show no evidence of distant metastasis, indicating that the patient is suitable for localized treatment. * ECOG performance status of 0-1: Patients must have an ECOG performance status score of 0-1 (as per Attachment 1), indicating that they are clinically in good physical condition and able to perform daily activities independently. * Informed consent: The patient and their family members must voluntarily sign an informed consent form after being fully informed of the purpose, content, risks, and potential benefits of the study, consenting to participate in the research. Exclusion Criteria: * Patients with unresectable tumors: This includes patients with tumors extensively invading vital organs (e.g., major blood vessels, spine, heart) or those for whom complete surgical resection is not feasible. * Patients with severe comorbidities: These include individuals with severe cardiovascular diseases (e.g., heart failure, history of myocardial infarction, arrhythmia), severe respiratory diseases (e.g., chronic obstructive pulmonary disease, severe asthma), or other uncontrolled systemic diseases that may affect the patient's ability to tolerate surgery safely. * Patients with distant metastasis: This includes patients with imaging findings suggestive of metastasis to distant organs, such as the liver, bones, or brain. * Patients with allergies to anesthetic agents or contraindications to anesthesia: This includes patients with a history of severe allergies or those with significant pulmonary or cardiovascular comorbidities that increase the anesthesia risk. * Pregnant or lactating women: Due to potential risks associated with radiological examinations (e.g., PET scans) and surgery for the fetus or infant. * Patients with psychiatric disorders or those unable to comprehend the informed consent form: This includes patients who are unable to provide independent informed consent or fully understand the study protocol and associated risks. * Patients unable to comply with follow-up requirements: This includes patients who are unable to attend scheduled postoperative follow-up visits, such as those living far from the hospital or with other logistical barriers. * Patients with concurrent malignant hematologic diseases or other primary cancers: This includes patients who have other primary malignancies, especially those with high recurrence risks, in addition to lung cancer. * Patients with known immune deficiencies or immune system disorders: This includes patients with severe immunodeficiency diseases, HIV, a history of organ transplantation, or other conditions that may compromise postoperative recovery and affect the efficacy of antitumor treatments. * Elderly patients unable to tolerate surgery or anesthesia: This includes elderly individuals with multiple chronic conditions or functional decline, making them unable to tolerate surgical risks. * Patients with severe hepatic or renal dysfunction: This includes patients with liver cirrhosis, renal failure, or other severe organ dysfunction that may prevent them from tolerating surgery and postoperative treatments. * Patients with active infections: This includes patients with active infectious diseases, such as pneumonia being treated with antibiotics, especially those with contagious conditions such as tuberculosis or bacterial pneumonia. * Patients with severe diabetes: This includes patients with unstable blood sugar control and diabetes-related complications (e.g., diabetic retinopathy, diabetic foot) that may complicate postoperative recovery. * Patients currently participating in other clinical trials: This includes patients enrolled in other clinical studies whose treatments may interfere with the interventions in this study. * Patients with severe malnutrition: This includes patients with significant weight loss or malnutrition that may impair postoperative recovery and increase anesthesia risk. * Patients with severe hematological disorders: This includes patients with conditions such as anemia or thrombocytopenia, which could complicate hemostasis during surgery and postoperative recovery. * Patients with severe chronic respiratory failure: This includes patients who are long-term ventilator-dependent or require tracheostomy, as they may have a higher surgical risk and compromised postoperative recovery.