What are the causes of small cell lung cancer

The incidence of small cell lung cancer is increasing day by day. Suffering from this disease can be said to be a disaster for a family. When you are sick, you have to find out the cause in your daily life to avoid serious illness. How can you know what the cause is? With this question, let us understand the causes of small cell lung cancer.

Small cell lung cancer is a relatively unique subtype of lung cancer, accounting for about 15-20 percent of lung cancer. As the name implies, its cancer cells are relatively small in morphology. Compared with non-small cell lung cancer, small cell lung cancer cells are small in size, but they have greater activity energy and are more likely to metastasize early, especially to the brain. About two-thirds of patients are already in the late stage when diagnosed, with faster disease progression and worse biological behavior. This feature determines that its treatment plan is different from non-small cell lung cancer, and the treatment of small cell lung cancer emphasizes systemic treatment. Therefore, systemic chemotherapy is an important treatment for small cell lung cancer, and surgery is not the main treatment.

The combination of radiotherapy and EP regimen is currently the best treatment option for limited-stage small cell lung cancer. In particular, early participation in radiotherapy is significantly better than late participation. Generally, radiotherapy is given 1-2 cycles after the start of chemotherapy, which can achieve relatively satisfactory results. Routine chest radiotherapy is not recommended for extensive-stage small cell lung cancer because it does not improve survival. Radiotherapy can also be used to prevent and treat brain metastases, spinal cord compression, and superior vena cava syndrome, etc. However, if it is extensive-stage small cell lung cancer with complete remission of distant metastases, concurrent chemoradiotherapy of chest lesions may have survival benefits.

Small cell lung cancer is very sensitive to chemotherapy. When treating limited-stage small cell lung cancer, about 40% to 70% of patients have complete disappearance of lesions, and extensive-stage small cell lung cancer can also achieve 20% complete remission. In recent years, some new drugs and new combination chemotherapy regimens have been used in the treatment of small cell lung cancer, including irinotecan, paclitaxel, ifosfamide, topotecan, gemcitabine, lobaplatin, amifopibicotin, pemetrexed, etc. Single-drug or combined chemotherapy provides more options and more hope and opportunities for patients.

Pathophysiology: It is generally believed that small cell lung cancer originates from Kulchitsky cell silver-loving cells in the bronchial mucosa or glandular epithelium and belongs to APUD tumor. Some people also believe that it originates from stem cells in the bronchial mucosal epithelium that can differentiate into neuroendocrine. Small cell lung cancer is the least differentiated and most malignant type of lung cancer. It often occurs in the central part of the lung, grows rapidly, and metastasizes early. Under a light microscope, the cancer cells are small and short spindle-shaped or lymphocyte-like, with less cytoplasm and a naked nucleus. Cancer cells are densely arranged in groups, separated by connective tissue, and sometimes cancer cells are arranged in groups around small blood vessels. Electron microscopic observation of ultrastructure shows that the tumor cell cytoplasm contains typical axon-like neuroendocrine granules, but the amount of granules varies, and it is proved to be related to 5-HT and ACTH. From the immunohistochemical study, tumor cells are positive for NSE, 5-HT, CgA, and some cases 10% are positive for Sy, proving that small cell carcinoma has neuroendocrine function. In addition, positive immunohistochemical reactions are simultaneously shown for CK and EMA in the same tumor.

Causes of disease: Smoking is the main risk factor for lung cancer, and SCLC is closely related to smoking. According to a summary analysis of smoking and lung cancer worldwide from 1970 to 1999, lung cancer is positively correlated with smoking intensity and duration, and the relationship with SCLC is most obvious.

Pathogenesis: In the past few decades, there have been many studies on the molecular mechanism of SCLC, suggesting that the occurrence of SCLC may involve the participation of multiple genes. Some studies have shown that the tumor suppressor gene p53, RB gene, neuroblastoma gene, oncogene Bcl-2 gene, Myc gene, signal transduction pathways, etc. are all related to the occurrence of SCLC.

Prevention methods Prevention of lung cancer is better than cure, and there are three levels of prevention. Prevention is for healthy people, mainly including not smoking and staying away from secondhand smoke pollution. Try to avoid outdoor air pollution and kitchen fumes. Choose environmentally friendly decoration materials. Eat a balanced diet, eat more grains, vegetables, and fruits. Maintain an optimistic and positive attitude towards life and improve psychological adaptability. Prevention is rehabilitation prevention. Lung cancer patients should follow the doctor's advice and go to the hospital for regular checkups.