What are the symptoms of lung cancer

The clinical manifestations of lung cancer are relatively complex. The presence, severity, and early or late onset of symptoms and signs depend on the site of the tumor, pathological type, presence or absence of metastasis and complications, as well as differences in the patient's response and tolerance. Early symptoms of lung cancer are often mild, or even without any discomfort. Symptoms of central lung cancer appear early and are severe, while symptoms of peripheral lung cancer appear late and are mild, or even asymptomatic, and are often discovered during physical examinations. The symptoms of lung cancer are roughly divided into: local symptoms, systemic symptoms, extrapulmonary symptoms, and infiltration and metastasis symptoms.

(I) Local symptoms

Local symptoms refer to symptoms caused by the tumor itself irritating, blocking, infiltrating and compressing tissues as it grows locally.

1. Cough

Cough is the most common symptom, accounting for 35% to 75% of patients with cough as the first symptom. Cough caused by lung cancer may be related to changes in bronchial mucus secretion, obstructive pneumonia, pleural invasion, atelectasis and other intrathoracic complications. When the tumor grows in the bronchial mucosa above the segment with a larger diameter and sensitive to external stimuli, it can cause cough similar to that caused by foreign body stimulation. The typical manifestation is paroxysmal irritating dry cough, which is often difficult to control with general cough suppressants. When the tumor grows in the smaller bronchial mucosa below the segment, the cough is often not obvious or even absent. For patients who smoke or suffer from chronic bronchitis, if the cough becomes more severe, the frequency changes, and the nature of the cough changes, such as a high-pitched metallic sound, especially in the elderly, you should be highly alert to the possibility of lung cancer.

2. Blood in sputum or hemoptysis

Blood in sputum or hemoptysis is also a common symptom of lung cancer, accounting for about 30% of the first symptoms. Because tumor tissue is rich in blood supply and brittle in texture, blood vessels rupture and cause bleeding during severe coughing. Hemoptysis may also be caused by local tumor necrosis or vasculitis. The characteristics of lung cancer hemoptysis are intermittent or continuous, repeated small amounts of blood in sputum, or small amounts of hemoptysis, occasionally due to large blood vessel rupture, large cavity formation or tumor rupture into the bronchial and pulmonary blood vessels, leading to uncontrollable hemoptysis.

3. Chest pain

About 25% of patients have chest pain as the first symptom. It often manifests as irregular dull pain or pain in the chest. In most cases, peripheral lung cancer invades the parietal pleura or chest wall, which can cause sharp and intermittent pleural pain. If it continues to develop, it will evolve into constant drilling pain. Mild chest discomfort that is difficult to locate is sometimes related to central lung cancer invading the mediastinum or involving blood vessels and peripheral bronchial nerves, and 25% of patients with malignant pleural effusion complain of dull chest pain. Continuous, sharp and severe chest pain that is not easily controlled by drugs often indicates that there has been extensive pleural or chest wall invasion. Persistent pain in the shoulders or chest and back indicates that there may be tumor invasion near the mediastinum on the inner side of the lung lobe.