【Major Points】

1. Lung cancer can be divided into small cell lung cancer and non-small cell lung cancer.
2. Patients with symptoms of long-term cough, short of breath, hemoptysis…etc., should seek medical attention of the department of Thoracic Medicine as soon as possible. 
3. Chest computed tomography, bronchoscopy, and biopsy can diagnose lung cancer.
4. The treatment of lung cancer includes surgery, chemotherapy, radiation therapy, etc.

What is lung cancer? 
The normal cells in the lungs grow abnormally and eventually become tumors, which is called lung cancer. In general, lung cancer cells can be classified into "small cell carcinoma" and "non-small cell carcinoma" based on the type of lung cancer cells that are found in the biopsy.

1. Small cell lung cancer accounts for about 20-25% of all lung cancers, and is most related to smoking. Around 90% of the patients have the habit of smoking. 
2. Non-small cell lung cancer accounts for 75~80%, and is subdivided into squamous cell carcinoma, lung adenocarcinoma, large cell lung cancer, etc. The real cause of lung cancer is still unclear, but the possible causes are:
   1. Chronic lung inflammation: such as chronic bronchitis, emphysema, and tuberculosis.
   2.  Prolonged exposure to hazardous environments: air pollution, exposure to asbestos, exposure to metal substances that easily cause the cells to mutate (eg: chromium, uranium, etc.)
   3. Family medical history: If more than two immediate family members have lung cancer, then the chances of getting lung cancer are relatively high.

1. A persistent cough that does not improve after a long time. 
2. Feelings of chest tightness or tingling when coughing or breathing deeply. 
3. The coughed up phlegm is bloodshot or bloody. 
4. Shortness of breath, or feeling short of breath. 
5. The voice is hoarse.
6. Unexplained loss of appetite and weight loss.

1. Chest X-ray: Monitor the lungs for abnormalities, but cannot detect tumors smaller than 1 cm.
2. Chest computed tomography: It can determine the size and location of lung tumors, and can monitor tumors smaller than 1 cm.
3. Bronchoscopy: detection rate of lung cancer is 90%. (More information: Bronchoscopy)
4. Thoracic ultrasound biopsy or computed tomography-guided biopsy: sampling of tumors can be obtained, and could help determine the location of lung abnormalities. The detection rate is 96%.

1. Surgical treatment: Surgical resection is the main treatment for early stage lung cancer.
2. Radiation therapy: Directly irradiating lung or metastases tumors with high-dose radiation to relieve uncomfortable symptoms. (More information: Care of Patient with Radiation-Induced Skin Reactions)
3. Chemotherapy: The use of chemical drugs to inhibit the growth of cancer cells, causing them to shrink. (More information: Care of Patient with Chemotherapy).
4. Targeted therapy: suitable for patients with non-small cell lung cancer, it is a drug developed for specific gene mutations, so patients must first go through genetic testing to determine if it applies. 
5. Immunotherapy: The immune effect is generated after injection of drugs to fight the growth of cancer cells. Common side effects include skin rash and diarrhea.
   1. Regular skin care: avoid hot baths, hot springs, and steam baths, etc. Please pay attention to sun protection when going out, do not wear tight-fitting or rough material clothing. You can use moisturizing lotion, but if there is a more serious condition, the doctor may prescribe medicinal ointment.
   2. Diarrhea care: When you have diarrhea symptoms, you should be sure to hydrate appropriately, temporarily reduce the consumption of high-fiber and greasy foods. When the symptoms are severe, you may use the anti-diarrheal medicine prescribed by the doctor.

1. Hsieh, H. H., Chiang, C. L., & Chiu, C. H. (2021). Diagnosis and treatment of small cell lung cancer. Clinical Medicine, 87(6), 373-380. https://doi.org/10.6666/ClinMed.202106_87(6).0062
2. Hwang, S. Y., Kim, J. Y., Lee, H. S., Lee, S., Kim, D., Kim, S., Hyun, J. H., Shin, J. I., Lee, K. H., Han, S. H., & Song. Y. G. (2021). Pulmonary tuberculosis and risk of lung cancer：A systematic review and meta-analysis. Journal of Clinical Medicine, 11(3), 765. https://doi.org/10.3390/jcm11030765
3. Shen, C. Y., & Chiu, C. H. (2021). The role and application of low-dose computed tomography in lung cancer screening. Clinical Medicine, 87(5), 277-282. https://doi.org/10.6666/ClinMed.202105_87(5).0045