Lung Cancer: Causes, Symptoms, Diagnosis, Treatment, and Prevention
One kind of cancer that begins in the lung cells is lung cancer. It is one of the most prevalent and fatal malignancies in the world, taking the lives of almost two million people annually. Symptoms of lung cancer might include weight loss, chest discomfort, coughing, and shortness of breath. Numerous causes, including smoking, exposure to chemicals, genetic alterations, and infections, can result in lung cancer. Imaging studies, biopsies, and physical examinations can all be used to identify lung cancer. Options for treatment include immunotherapy, targeted therapy, radiation therapy, chemotherapy, and surgery.
Causes
Lung cancer is mainly caused by changes in the DNA of the lung cells that make them grow and divide abnormally. These changes can be inherited or acquired during one’s lifetime. Some of the common causes of lung cancer are:
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The primary risk factor for lung cancer and other cancers is smoking. Smoking alters lung cells' DNA and raises the possibility of mutations that might result in cancer. The amount of cigarettes smoked, the length of time smoked, and the age at which smoking began all raise the risk of lung cancer.
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Exposure to pollutants that can harm lung cell DNA and raise the risk of lung cancer, such as air pollution, radon, asbestos, and secondhand smoking. These poisons may be present in some jobs like mining, construction, or manufacturing.
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Mutations in genes that might increase the risk of lung cancer in lung cells, such as those related to EGFR, KRAS, ALK, or ROS1. These mutations may result from environmental causes, random mistakes, or inheritance from one's parents. Certain medications have the ability to target certain of these alterations, blocking their effects and slowing the development of cancer cells.
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Infections that can impair immunity and make it more difficult for the body to fight off the aberrant lung cells, such as HIV, TB, and human papillomavirus (HPV). Additionally, certain infections have the direct ability to alter lung cells' DNA, turning them malignant.
Symptoms
Lung cancer may not cause any symptoms in its early stages, and may be detected by a routine chest X-ray or CT scan. However, as the cancer grows and spreads, it can cause various symptoms, such as:
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Coughing, which may be persistent, dry, or productive of blood or mucus
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Chest pain, which may be sharp, dull, or aching, and may worsen with breathing, coughing, or lying down
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Shortness of breath, which may be due to the cancer blocking the airways, compressing the lungs, or causing fluid to build up in the chest
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Weight loss, which may be due to the cancer consuming more calories, reducing the appetite, or causing nausea or vomiting
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Other symptoms, such as fatigue, weakness, fever, night sweats, hoarseness, or difficulty swallowing, which may be due to the cancer affecting other organs or systems of the body
Diagnosis
A physician will inquire about the patient's symptoms, medical history, and risk factors in order to make a diagnosis of lung cancer. In addition, the physician will do a physical examination to look for physical indicators of lung cancer, such as fluid in the chest, swollen lymph nodes, or unusual breath sounds. In order to confirm the diagnosis and identify the kind and stage of lung cancer, the doctor may additionally prescribe certain tests, such as:
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Imaging tests, such as chest X-ray, CT scan, MRI, or PET scan, that can show the size, location, and spread of the tumor in the lungs and other parts of the body
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Biopsy, which is a procedure that involves taking a sample of the tumor tissue and examining it under a microscope to confirm the presence of cancer cells and identify their characteristics
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Molecular testing, which is a type of laboratory test that can analyze the DNA of the cancer cells and detect specific mutations that can guide the treatment and prognosis of lung cancer
Treatment
The stage, kind, and location of the tumor, in addition to the patient's general health and preferences, all influence the course of treatment for lung cancer. The major objectives of treatment are to eliminate or eradicate the cancer cells, stop or postpone the disease's spread or recurrence, and enhance the patient's quality of life. The available treatments might consist of:
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Surgery entails removing the tumor along with surrounding healthy tissue from the lung. It can be performed using traditional open methods or minimally invasive techniques like video-assisted thoracoscopic surgery (VATS) or robotic surgery. Surgery may be supplemented with other treatments such as chemotherapy or radiation therapy to enhance curative prospects or prevent cancer recurrence.
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Chemotherapy, a form of drug therapy, employs chemicals to halt the growth or kill cancer cells. It can be administered pre or post-surgery or serve as the primary treatment for advanced or metastatic lung cancer. Chemotherapy may be delivered intravenously or orally, either as a standalone therapy or in conjunction with other medications.
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Radiation therapy uses high-energy rays or particles to disrupt or obliterate the DNA of cancer cells. It can precede or follow surgery or serve as the primary treatment for inoperable or metastatic lung cancer. Radiation therapy may be administered externally through a machine or internally by placing radioactive material near the tumor.
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Targeted therapy is a drug-based treatment that targets specific molecules or pathways vital for cancer cell growth and survival. It may be employed for lung cancer harboring specific genetic mutations like EGFR, ALK, or ROS1, which heighten sensitivity to these drugs. Targeted therapy may be given intravenously or orally, alone or in combination with other medications.
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Immunotherapy utilizes drugs to activate or enhance the immune system's ability to combat cancer cells. It can be utilized for lung cancer exhibiting certain traits, such as elevated PD-L1 levels—a protein aiding cancer cells in evading the immune system. Immunotherapy is typically administered intravenously, either independently or alongside other medications.
Prevention
While certain instances of lung cancer may stem from genetic or environmental factors beyond individual control, proactive measures can help prevent or minimize its occurrence:
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Smoking Cessation: Quitting smoking stands as the most pivotal and effective means of preventing not just lung cancer, but various other cancers as well. Additionally, it diminishes the risk of diseases like heart disease, stroke, and chronic obstructive pulmonary disease (COPD).
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Avoidance of Toxins: Steer clear of harmful substances such as asbestos, radon, air pollution, and secondhand smoke, which heighten the risk of lung cancer. Certain occupations like mining, construction, or manufacturing may necessitate protective gear or regular screening due to exposure to these toxins.
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Healthy Diet: Adopting a nutritious and balanced diet replete with vitamins, minerals, antioxidants, and fiber bolsters the immune system, mitigating inflammation and oxidative stress that can harm lung cell DNA.
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Regular Exercise: Engaging in consistent and moderate physical activity enhances lung function and capacity while reducing the likelihood of obesity, diabetes, and cardiovascular disease—conditions that can also impact lung health and increase lung cancer risk.
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Routine Check-ups and Screenings: Regular medical check-ups and screenings aid in identifying and addressing potential lung health issues such as infections, diseases, or tumors. Screening for lung cancer, typically through a low-dose CT scan of the chest, facilitates early detection when curative prospects are highest.
