What are the causes of non-small cell lung cancer? What are the serious types of lung cancer?

What are the risk factors for non-small cell lung cancer?

When it comes to lung cancer, everyone knows about it, but when it comes to non-small cell lung cancer, few people may know it clearly. This article will ask you to explain in detail what it is.

Non-small cell lung cancer

Lung cancer has become the most common malignant tumor in my country and even in the world. Non-small cell lung cancer includes squamous cell carcinoma (SCC), adenocarcinoma, and large cell carcinoma. Compared with small cell carcinoma, its cancer cells grow and divide more slowly and spread later. About 80% of lung cancers are non-small cell lung cancers, but about 75% of patients are already in the middle and late stages when they are diagnosed, and the 5-year survival rate is very low.

Risk factors for non-small cell lung cancer

1. Smoking

Smoking is considered the highest risk factor for non-small cell lung cancer. This is because the polycyclic aromatic hydrocarbons (such as benzopyrene) and nitrosamines in tobacco have strong carcinogenic activity. They can cause DNA damage in bronchial epithelial cells, activate oncogenes, and inactivate tumor suppressor genes, which in turn causes cell transformation and ultimately leads to cancer.

2. Occupation and environment

Lung cancer is a very common occupational cancer. About 10% of lung cancer patients have a history of occupational and environmental exposure. Toxic substances and industrial waste gas are common factors that cause lung cancer.

3. Ionizing radiation

The lungs are more sensitive to radiation. If the amount of ionizing radiation is strong, it is very likely to cause non-small cell lung cancer. Many workers who work in the mining of radioactive ores will have a significantly increased incidence of the disease.

4. Air pollution

Because the polluted atmosphere contains many harmful substances such as benzopyrene carcinogenic hydrocarbons, which are the main factors causing disease.

5. Genetics

Studies have shown that familial aggregation and genetic susceptibility mean that genetic factors may increase an individual's risk of disease.

Symptoms of non-small cell lung cancer

Patients in the early stage may experience chest pain, blood in sputum, low-grade fever, cough and other symptoms. If these symptoms occur, you should seek medical attention immediately. If it is in the late stage, there will be loss of appetite, weight loss, fatigue, and even difficulty breathing, hemoptysis, etc. It is difficult to achieve good treatment results at this stage.

Non-small cell lung cancer can be diagnosed through several medical methods, including X-ray examination, bronchoscopy, cytology examination, thoracotomy, ECT examination, and mediastinoscopy.

Treatment options for non-small cell lung cancer

1. Chemotherapy: Chemotherapy is also the main method for treating non-small cell lung cancer, but chemotherapy generally cannot cure the disease, and can only provide palliative treatment, with a remission rate of about 40% to 50%. This can prolong the patient's survival and improve the quality of life.

2. Radiotherapy: Radiotherapy is most effective for small cell lung cancer, followed by squamous cell carcinoma, and the worst for adenocarcinoma. Radiotherapy is generally used as a combined treatment with chemotherapy. However, complications may occur during radiotherapy.

3. Surgery: Surgery is the first and main treatment for lung cancer. However, due to the patient's physical condition, only a small number of people are suitable for surgery. And usually preoperative and postoperative adjuvant therapy is required.

I believe everyone has learned the main knowledge about non-small cell lung cancer. If you have friends who meet the symptoms, do not take it lightly and seek medical treatment as soon as possible.

What are the most serious types of lung cancer?

Lung cancer is generally divided into the following four types clinically, among which undifferentiated cancer has the worst prognosis and is the most serious. It is particularly important to understand the types of lung cancer and their severity. If patients know this knowledge, it will help with treatment. Specifically, there are the following types of lung cancer:

1. Squamous cell carcinoma (also known as squamous cell carcinoma): The most common type of lung cancer, accounting for more than 50% of patients. They mostly originate from larger bronchi, usually from central lung cancer. Although squamous cell carcinoma has different degrees of differentiation, its growth and development are generally slow and the course of the disease is long. It is more sensitive to radiation and chemotherapy. First, lymphatic metastasis and hematogenous metastasis occur. Later, it occurs.

2. Undifferentiated carcinoma: The incidence of undifferentiated carcinoma in men is lower than that of squamous cell carcinoma. It usually originates from bronchial central lung cancer. According to histological cell morphology, it can be divided into oatmeal cells, small round cells and large cells. Among them, oatmeal cells are the most common undifferentiated carcinoma, with high malignancy, high growth rate, and extensive lymphatic and hematogenous metastasis. Among all types of lung cancer, it has the worst prognosis.

3. Adenocarcinoma: A small number of mucous glands from the bronchial mucosal epithelium are more common in young women than those from squamous and undifferentiated carcinomas. Most adenocarcinomas originate from smaller bronchi. Peripheral lung cancer usually has no obvious clinical symptoms in the early stages. The round or oval mass usually grows slowly, but sometimes it is early on chest X-ray. Hematogenous metastasis and lymphatic metastasis occur later.

4. Alveolar cell carcinoma: Women with the lowest incidence of bronchoalveolar cell carcinoma or bronchoalveolar adenocarcinoma arising from bronchial mucosal epithelium are more likely to have higher differentiation and slower cancer cell growth along the bronchoalveolar ducts and alveoli. There is no alveolar septal lymph node infiltration and blood flow metastasis in the AR wall, but it can spread through the bronchi. For other lobes or invasive pleural epithelial cell carcinoma, there are two types: nodular and diffuse. The former can be a single nodule or multiple nodules, and the latter can be surgically removed by nodule surgery similar to limited-extent pneumonia lesions.

1. Squamous cell carcinoma (also known as squamous cell carcinoma): It is the most common type of lung cancer, accounting for about 50%. Most patients are over 50 years old, with the majority being men. Most of them originate from larger bronchi and are often central lung cancers. Although the degree of differentiation of squamous cell carcinoma varies, it generally grows and develops slowly, has a longer course of disease, and is more sensitive to radiation and chemotherapy. It first metastasizes through the lymph nodes, and hematogenous metastasis occurs later.

2. Undifferentiated carcinoma: Its incidence rate is second only to squamous cell carcinoma and it is more common in males at a younger age. It usually originates from larger bronchi and is a central lung cancer. According to the morphology of tissue cells, it can be divided into several types, such as oat cells, small round cells, and large cells. Among them, oat cells are the most common. Undifferentiated carcinoma has a high malignancy, grows rapidly, and metastasizes widely to the lymph nodes and bloodstreams at an early stage. It is more sensitive to radiation and chemotherapy and has the worst prognosis among all types of lung cancer.

3. Adenocarcinoma: Originates from the bronchial mucosal epithelium. A small number of them originate from the mucous glands of large bronchi. The incidence rate is lower than that of squamous cell carcinoma and undifferentiated carcinoma. It is more common in women at a younger age and most adenocarcinomas originate from smaller bronchi. They are peripheral lung cancers. There are usually no obvious clinical symptoms in the early stages and they are often discovered during chest X-ray examinations. They appear as round or oval masses and generally grow slowly, but sometimes they have hematogenous metastasis in the early stages. Lymphatic metastasis occurs later.

4. Alveolar cell carcinoma: Originates from the bronchial mucosal epithelium, also known as bronchioalveolar cell carcinoma or bronchiolar adenocarcinoma. It is located around the lung field and has the lowest incidence among all types of lung cancer. It is more common in women and is generally highly differentiated and grows slowly. Cancer cells grow along the bronchioalveolar ducts and alveolar walls without invading the alveolar septum. Lymphatic and hematogenous metastasis occurs later but can spread to other lung lobes through the bronchi or invade the pleura. Alveolar cell carcinoma has two morphological types: nodular and diffuse. The former can be a single nodule or multiple nodules; the latter has a morphology similar to pneumonia. The nodular type with limited lesions has a better therapeutic effect after surgical resection.