Lung Cancer: Causes, Types, Symptoms and Risk Factors

Lung cancer originates from the lungs. Your lungs are two spongy organs in your chest that release carbon dioxide when you breathe in. Oxygen comes here first. Lung cancer accounts for the majority of cancer-related deaths worldwide.

Smokers are more at risk for developing lung cancer, however, it can happen to nonsmokers as well. One's risk of developing lung cancer is increased by the quantity and duration of cigarette smoking. Giving up smoking, especially if you have smoked for a long period, can significantly reduce your chance of developing lung cancer.

Causes Of Lung Cancer

Smoking is the primary cause of lung cancer in both smokers and secondhand smoke exposure victims. On the other hand, lung cancer may develop in people who have never smoked or who have never spent a significant amount of time around secondhand smoke. In certain cases, lung cancer may have no recognized etiology.

How smoking causes lung cancer

According to medical experts, smoking destroys the cells lining the lungs, increasing the risk of lung cancer. Lung tissue rapidly changes when inhaled cigarette smoke, a concoction of substances known as carcinogens that cause cancer.

At initially, your body may be able to repair this injury. But with every exposure, the healthy cells lining your lungs suffer additional damage. Over time, damage to cells causes them to act abnormally, potentially leading to cancer.

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Types of lung cancer

Physicians categorise lung cancer into two primary groups based on the microscopic appearance of the cancer cells. The course of treatment will be determined by your doctor based on the primary kind of lung cancer you have.

Lung cancer can be of two broad types:

• Small-cell lung cancer. Small cell lung cancer is almost exclusively seen in heavy smokers, while being less common than non-small cell lung cancer.
• Non-small cell lung cancer. A general term for a range of kinds of lung cancer is "non-small cell lung cancer." Lung cancer kinds that do not contain microscopic cells are scleromatosis, adenocarcinoma, and large cell carcinoma.

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Symptoms Of Lung Cancer

Lung cancer typically exhibits no symptoms at all in its early stages. Signs and symptoms of lung cancer typically arise after the disease has advanced.

Signs and indications of lung cancer may include:

• A recent cough that continues 
• Blood in cough, even a small amount of it
• Lack of breath
• Chest pain
• The sibilant tone of voice
• Gaining physical fitness without exerting yourself
• Bone pain
• Headache

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Risk Factors of Lung Cancer

Several factors may increase one's risk of lung cancer. One risk factor that may be controlled is quitting smoking. Furthermore, certain factors are beyond your control, such as your family history.

Risk factors for lung cancer include:

• Smoking. Even for nonsmokers, secondhand smoke exposure increases the risk of lung cancer.
• Previous exposure to radiation. If you have radiation treatment to the chest for any other type of cancer, you could be more vulnerable to lung cancer.
• Being exposed to radon gas. Radon is released from the natural decay of uranium in soil, rock and water. Radon eventually makes its way into the air you breathe. Dangerously elevated radon levels can occur in any kind of building, even residential ones.
• Exposure to other dangerous substances including asbestos. Especially if you smoke, occupational exposure to asbestos and other carcinogens like nickel, chromium, and arsenic can raise your risk of developing lung cancer.
• A family history of lung cancer. Those who have a parent, sibling, or child with the disease are more likely to develop lung cancer themselves.

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Diagnosis Of Lung Cancer

Screening for lung cancer in healthy individuals

Individuals who are more susceptible to lung cancer can think about getting screened for the disease every year with low-dose CT scans. Older persons who have smoked extensively for a long time or who have stopped within the last 15 years are often offered a lung cancer screening.

Talk to your physician about your risk of lung cancer. You and your partner can determine if screening for lung cancer is appropriate for you.

Examinations for the diagnosis of lung cancer

To rule out other disorders and search for malignant cells, your doctor may perform a series of tests if there is cause to believe that you may have lung cancer.

Tests might consist of:

• Imaging examinations. An abnormal lump or nodule may be visible on an X-ray scan of your lungs. Small lung lesions that might not be seen on an X-ray can be found on a CT scan.
• Cytology of Sputum. When you cough and produce sputum, examining the phlegm under a microscope can occasionally identify lung cancer cells.
• Biopsy sample of tissue. A biopsy is a technique where a sample of aberrant cells is removed.

There are several methods your doctor can use to do a biopsy, such as a bronchoscopy, wherein your doctor uses a lit tube inserted down your neck and into your lungs to inspect abnormal parts of your lungs.

Another option is mediastinoscopy, which involves making an incision at the base of your neck and inserting surgical instruments behind your breastbone to remove tissue samples from lymph nodes.

Another alternative is a needle biopsy, in which your physician guides a needle through your chest wall and into the lung tissue to collect abnormal cells using pictures from an X-ray or CT scan. A sample for a biopsy may also be obtained from your liver or other lymph nodes or other locations where the cancer has progressed.

Your form of lung cancer will be identified by a meticulous investigation of your cancer cells in a lab. The precise properties of your cells, which can assist predict your prognosis and direct your therapy, can be revealed to your doctor by the results of advanced tests.

Examinations to determine the cancer's extent

Your doctor will try to ascertain the stage (or extent) of your lung cancer once it has been detected. The stage of your cancer plays a key role in determining the best course of action for you and your doctor.

Imaging techniques that enable your doctor to search for proof that cancer has spread outside of your lungs may be part of the staging tests. These examinations include of bone scans, positron emission tomography (PET), CT, and MRI. You should discuss with your doctor which treatments are best for you as not every test is acceptable for every individual.

Roman numerals 0 through IV represent the different stages of lung cancer, with the lowest stages denoting lung-specific malignancy. When a cancer reaches stage IV, it is thought to have progressed and to have spread to other bodily parts.

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Treatment Of Lung Cancer

The kind and stage of your cancer, your preferences, and your general health are all taken into consideration when you and your doctor decide on a treatment plan.

You could decide not to get therapy in specific circumstances. For example, you could believe that the negative consequences of the treatment would exceed any possible advantages. If such is the case, your doctor could recommend comfort therapy, which would simply address the discomfort or dyspnea that the malignancy is producing.

Surgery

Your surgeon will try to remove a margin of healthy tissue in addition to the lung cancer during the procedure. Among the methods used to eliminate lung cancer are:

• Wedge resection to excise the tumor-containing portion of the lung together with a margin of healthy tissue
• Segmental resection involves removing a greater area of the lung without removing the complete lobe.
• To remove a single lung lobe entirely, do a lobectomy.
• A pneumonectomy in which the whole lung is removed

Your surgeon could remove lymph nodes from your chest during surgery so they can be examined for cancerous growths. To reduce the size of the lung cancer before surgery, your doctor could advise chemotherapy or radiation therapy if your cancer is further advanced.

 Your doctor can suggest chemotherapy or radiation therapy following surgery if there's a chance that cancer cells were left over from the procedure or if there's a chance your cancer will return.

Radiation Treatment

High-powered energy beams from sources like protons and X-rays are used in radiation treatment to destroy cancer cells. Radiation therapy involves lying on a table with a machine positioned around you to target certain areas of your body with radiation.

Patients with locally advanced lung cancer may get radiation therapy either before to or following surgery. It frequently goes along with chemotherapy. Your main course of treatment may involve a combination of chemotherapy and radiation therapy if surgery is not an option.

Radiation treatment may be used to treat advanced lung cancers and those that have metastasized to other parts of the body in order to reduce symptoms like discomfort.

Chemotherapy

Drugs are used in chemotherapy to destroy cancer cells. Chemotherapy medications can be administered orally or intravenously, through a vein in your arm. Usually, a series of treatments consisting of a mix of medications are administered over a period of weeks or months, with gaps to allow for recovery in between.

Chemotherapy is frequently used to eradicate any cancer cells that may have persisted following surgery. Both alone and in conjunction with radiation therapy, it can be employed. Chemotherapy can also be used to reduce tumours and facilitate their removal prior to surgery.

Chemotherapy can help patients with advanced lung cancer manage their pain and other symptoms.

Using stereotactic body radiotherapy

A powerful radiation therapy called stereotactic body radiotherapy, also referred to as radiosurgery, directs several radiation beams at the malignancy from a variety of angles. Treatment for stereotactic body radiation usually takes one or more sessions to complete.

For patients with tiny lung malignancies who are not candidates for surgery, stereotactic body radiation treatment may be an alternative. Additionally, it can be used to treat lung cancer that has metastasized to other organs, such as the brain.

Targeted Drug Therapy 

Specific abnormalities seen in cancer cells are the focus of targeted pharmacological therapy. Targeted pharmacological therapies can kill cancer cells by obstructing these anomalies.

Although most of the medications used in targeted therapy are only for patients with advanced or recurring lung cancer, there are several such drugs available.

Certain cancer cells with certain genetic alterations are the only ones that respond well to some targeted therapy. A laboratory may analyse your cancer cells to see whether these medications might be beneficial to you.

Immunotherapy

Immunotherapy fights cancer by boosting your immune system. The immune system that fights illness may not be able to combat your cancer because the cancer cells make proteins that assist them evade the immune system cells. Immunotherapy functions by obstructing that process.

Patients with locally advanced lung cancer and malignancies that have metastasized to other areas of the body are often the only ones eligible for immunotherapy therapies.

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Prevention Of Lung Cancer

While there is no way to totally prevent lung cancer, you can reduce your risk if you:

• Avoid smoking. If you have never smoked, do not begin. Talk to your children about giving up smoking so they may learn how to lower their exposure to this important lung cancer risk factor. Early education on the dangers of smoking will help your children deal with peer pressure.
• Give up the smokes. Quit smoking straight now. You can reduce your risk of lung cancer even if you have been a smoker for a long time by quitting. Speak with your doctor about safe and effective products and techniques for quitting. Nicotine replacement therapy, medications, and support groups are available. 
• Avoid being around people who are smoking. Urge your flatmate or coworker who smokes to stop. At minimum, ask them to smoke outside. Look for smoke-free options and avoid areas where people smoke, such as restaurants and bars.
• Inspect your home for radon. In particular, if you live in an area where radon contamination is known to be a problem, check the radon levels in your home. Remedial of elevated radon levels may make your home safer. For information on radon testing, get in contact with the public health department or the local branch of the American Lung Association. 
• Avoid exposure to carcinogens while working. Protect yourself from dangerous chemical exposure at work by taking preventative action. Take actions as instructed by your employer. Wear your face mask at all times, for example, if one is given to you for protection. What other precautions can you take at work to keep yourself safe? Talk to your physician about it. Smoking increases your chance of lung damage from chemicals used in the workplace that cause cancer.
• Eat plenty of fruits and vegetables in your diet. Select a variety of fruits and vegetables for a well-rounded diet. The best source of vitamins and minerals is diet. Large doses of vitamin tablets should be avoided as they might be dangerous. 

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Complications Of Lung Cancer

Lung cancer can cause a number of challenges, including:

• Difficulty breathing. Patients with lung cancer may get breathless if the disease progresses to the point where it obstructs one or more major airways. Furthermore, the accumulation of fluid around the lungs caused by lung cancer may prevent the affected lung from expanding completely when breathing in. 
• Coughing up blood. Coughing up blood, or hemoptysis, is one of the probable adverse effects of airway bleeding associated with lung cancer. Sometimes there might be severe bleeding. To control bleeding, there are treatments available.
• Pain. Advanced lung cancer may cause pain if it spreads to the lining of the lung or to another area of the body, such as the bone. There are several strategies to handle discomfort, so let your doctor know if you're in pain.
• Pleural effusion, or chest fluid. Lung cancer patients may have pleural space filling with fluid in the region of the chest cavity surrounding the injured lung. One may become breathless due to a collection of fluid in the chest. There are methods to reduce the chance of developing another pleural effusion and release the pressure in your chest. 
• Cancer that has metastasized is when it spreads to other bodily parts. The illness usually spreads to other organs, such as the brain and bones, when lung cancer metastasizes. Cancer that spreads may cause discomfort, nausea, headaches, or other symptoms, depending on which organ is affected. If lung cancer has spread to other parts of the body, it is often incurable. There are treatments to help you reduce symptoms and live a longer life.

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