Is lung function in the early stage of lung cancer

FENO detection of lung function is not an early diagnostic indicator for lung cancer, but mainly used to evaluate airway inflammation. The clinical significance of FENO exhaled nitric oxide detection includes asthma monitoring, differentiation of chronic cough, assessment of airway inflammation, etc. It is not directly related to the diagnosis of lung cancer. Lung cancer screening requires a combination of low-dose CT, tumor markers, pathological biopsy, and other methods.

1. FENO detection principle:

FENO detection reflects the level of airway inflammation by measuring the concentration of nitric oxide in exhaled gas. Nitric oxide is produced by airway epithelial cells and is significantly elevated in eosinophilic inflammation. The testing process requires the subject to exhale continuously for 6-10 seconds, and the instrument automatically analyzes the gas composition. The diagnostic value of this technology for allergic diseases such as asthma has been recognized by international guidelines.

2. Assessment of airway inflammation: Elevated FENO values are common in diseases such as eosinophilic bronchitis and allergic rhinitis. The normal value for adults is usually below 25ppb, while asthma patients can reach 50-300ppb. This indicator can effectively predict hormone therapy responsiveness and guide medication adjustments for asthma patients. However, it should be noted that factors such as smoking and viral infections may lead to false negative results.

3. Diagnosis of lung cancer:

Diagnosis of lung cancer relies on imaging and pathological examinations. Low dose CT can detect pulmonary nodules larger than 2 millimeters, while enhanced CT can evaluate the blood supply characteristics of the lesion. Tumor markers such as CEA and CYFRA21-1 have auxiliary value. The final diagnosis requires obtaining tissue specimens through bronchoscopy biopsy or percutaneous lung puncture for pathological examination.

4. Differences in examination items:

FENO testing and lung cancer screening belong to different dimensions of examination. The former focuses on functional evaluation, while the latter focuses on structural abnormalities. FENO is often combined with pulmonary ventilation function testing in clinical practice, while lung cancer screening requires a combination of imaging features and malignant risk prediction models. The indications, operating procedures, and interpretation of results for the two types of examinations are fundamentally different.

5. Screening of high-risk populations:

Long term smokers, asbestos exposed individuals, and other high-risk groups for lung cancer are recommended to undergo low-dose CT scans annually. International lung cancer screening research shows that regular screening can reduce lung cancer mortality by 20%. If pulmonary nodules are found, a follow-up plan should be developed based on the size and density characteristics of the nodules, and multidisciplinary consultation evaluation should be initiated if necessary. Regular physical examinations are key to early detection of lung diseases. It is recommended that people over 40 years old undergo chest X-ray examination every year, and smokers need to increase lung function testing. Maintaining indoor air circulation, avoiding exposure to cooking fumes, and supplementing with antioxidant nutrients such as vitamin A/C can help maintain respiratory health. When symptoms such as persistent cough and bloody sputum appear, timely medical attention should be sought from the respiratory department, and relevant examinations should be conducted to clarify the cause.