Lung cancer occurs in bronchial mucosa epithelium, also known as bronchial lung cancer. Lung cancer generally refers to the cancer of lung parenchyma, and usually does not include mesothelioma originating from other lung cancers, or other malignant tumors such as carcinoid, malignant lymphoma, or tumors with metastasis from other sources. Therefore, lung cancer refers to malignant tumors from bronchi or bronchial epithelial cells, accounting for 90-95% of lung parenchymal malignant tumors.
Lung cancer is the leading cause of cancer death in the world. 1995 In the world, 600,000 people died of lung cancer, and this number is increasing every year. In 2003, the mortality rate announced by the World Health Organization was 165438+ 10,000/year, and the incidence rate was1.20,000/year. The incidence of female lung cancer is especially on the rise. The onset age of this disease is mostly over 40 years old, and the peak age of onset is between 60 and 79 years old. The prevalence rate of male and female is 2.3: 1. In addition, race, family history and smoking all have effects on the incidence of lung cancer. Lung cancer originates from bronchial mucosa epithelium and is confined to basement membrane, which is called carcinoma in situ. It can grow into bronchial cavity or/and adjacent lung tissue, and can spread through lymphatic blood circulation or bronchial metastasis. The growth rate, metastasis and spread of cancer are related to the histological type and differentiation degree of cancer.
Lung cancer is more distributed in the right lung than in the left lung, and the upper lobe is more than the lower lobe. Cancer can develop from the main bronchi to the bronchioles. Lung cancer originating from the main bronchus and lobar bronchus and located near the hilum is called central lung cancer; Lung cancer originating from the lower part of the segmental bronchus and located in the peripheral part of the lung is called peripheral lung cancer. There are no symptoms in the early stage. Almost two-thirds of lung cancer patients are in advanced stage (stage ⅲ or ⅳ), and 95% of them can have clinical examination results. Primary tumor, metastatic tumor, systemic symptoms or tumor-related symptoms may be the first symptoms of patients.
The first symptom caused by primary tumor accounts for 27%, and the symptoms are related to the location of primary tumor. Central lung cancer is characterized by irritating dry cough, breath holding, repeated pneumonia, hemoptysis or asthma at the same site, compression symptoms of recurrent laryngeal nerve and phrenic nerve or superior vena cava compression syndrome. The more common symptoms of peripheral tumors are chest pain, breath holding or pleural effusion. Peripheral large lesions, central necrosis and cavities eventually appear similar to lung abscess, and common symptoms of primary lung cancer are grouped.
After knowing the above knowledge, you will know what is common sense of lung cancer. Lung cancer will affect many friends and bring serious harm to their lung health. We need to correctly understand the knowledge of lung cancer, early treatment after the onset of lung diseases, and lung care should also be strengthened.