What are the early symptoms of lung metastasis from kidney cancer?

When kidney cancer metastasizes to the lungs, early symptoms mainly include: 1. Cough: Tumor cells may irritate the respiratory mucosa, leading to a dry cough or cough with sputum, sometimes accompanied by difficulty breathing. 2. Hemoptysis (blood in sputum): Necrosis and rupture of tumor tissue may allow blood to enter the airways, resulting in coughing up sputum mixed with blood, which is typically bright red, pink, or brownish. 3. Shortness of breath: Reduced lung function impairs oxygen exchange, causing worsening breathlessness during physical activity, possibly accompanied by wheezing. 4. Chest pain: Tumor pressure or traction on surrounding tissues can cause chest pain, which may be located in the center or on one side of the chest and often worsens with deep breathing or coughing. 5. Hoarseness: If the cancer spreads to lymph nodes and compresses the recurrent laryngeal nerve, it may lead to hoarseness.