Patients with lung cancer in the early stages may experience severe coughing, mild coughing, or no coughing symptoms at all. Many early-stage lung cancer patients have lesions located near the periphery of the lungs that do not involve the airways or other significant structures, typically resulting in no clinical symptoms. By the time clinical symptoms appear, the patient may already be in the middle or late stages of lung cancer. Additionally, it is important to note that some patients with early-stage lung cancer may also experience coughing, which can range from severe to mild, and may include coughing up blood. Such symptoms are often seen in early-stage central lung cancer, which frequently presents with cough and blood in the sputum. Therefore, older patients with a long history of smoking who suddenly develop a cough or start coughing up blood should be highly vigilant and likely need to undergo chest CT scans, bronchoscopy, and other related examinations for evaluation.