Basic information about lung cancer, cause symptoms treatment and prevention.
Lung cancer, recently one of our lady senator got a lung cancer, she said where she got it, she didn’t smoke or even her family. So, where she got it. What the cause of it.
Function of the lungs
The principal function of the lungs is to exchange gases between the air we breathe and the blood. Through the lung, carbon dioxide is removed from the bloodstream and oxygen from inspired air enters the bloodstream. The right lung has three lobes, while the left lung is divided into two lobes and a small structure called the lingula that is the equivalent of the middle lobe on the right. The major airways entering the lungs are the bronchi, which arise from the trachea. The bronchi branch into progressively smaller airways called bronchioles that end in tiny sacs known as alveoli where gas exchange occurs. The lungs and chest wall are covered with a thin layer of tissue called the pleura.
What is lung cancer?
Lung cancer is a malignant lung tumor, characterized by uncontrolled growth of abnormal cells that start off in one or both lungs; usually in the cells that line the air passages.
Malignant tumors, the more dangerous ones, spread to other parts of the body either through the bloodstream or the lymphatic system.
Benign tumors it’s the Tumors that remain in one place and do not appear to spread
Primary lung cancer originates in the lungs, while secondary lung cancer starts somewhere else in the body, metastasizes, and reaches the lungs.
How is lung cancer classified?
It classified into two main types based on the cancer's appearance under a microscope:
One is non-small cell lung cancer and second is small cell lung cancer.
Non-small cell lung cancer (NSCLC) can be divided into four different types, with different treatment options:
1. Squamous cell carcinoma or epidermoid carcinoma. The most common type of lung cancer in men, squamous cell carcinoma forms in the lining of the bronchial tubes.
2. Adenocarcinoma, the most common type of lung cancer in women and in nonsmokers, its forms in the mucus-producing glands of the lungs.
3. Bronchioalveolar carcinoma, a rare type of adenocarcinoma that forms near the lungs' air sacs.
4. Large-cell undifferentiated carcinoma. A rapidly growing cancer, large-cell undifferentiated carcinomas form near the outer edges or surface of the lungs.
Second is small cell lung cancer.
Small cell lung cancer (SCLC) is characterized by small cells that multiply quickly and form large tumors that travel throughout the body. Almost all cases of SCLC are due to smoking.
Small cell lung cancer has two stages: limited or extensive. In the limited stage, the tumor exists in one lung and in nearby lymph nodes. In the extensive stage, the tumor has infected the other lung as well as other organs in the body.
Cause of lung cancer
Most lung cancers are the result of inhaling carcinogenic substances.
What is a carcinogenic substance?
Carcinogens are a class of substances that are directly responsible for damaging DNA, promoting or aiding cancer. Arsenic, radiation such as gamma and x-rays, the sun, and compounds in car exhaust fumes are all examples of Carcinogens
Other example of Carcinogens
Smoking
The incidence of lung cancer is strongly correlated with cigarette smoking, with about 90% of lung cancers arising as a result of tobacco use.
Pipe and cigar smoking also can cause lung cancer, although the risk is not as high as with cigarette smoking.
Tobacco smoke contains over 4,000 chemical compounds, many of which have been shown to be cancer-causing or carcinogenic.
Passive smoking or the inhalation of tobacco smoke by nonsmokers, who share living or working quarters with smokers, also is an established risk factor for the development of lung cancer.
Asbestos fibers are silicate fibers that can persist for a lifetime in lung tissue following exposure to asbestos.
Radon gas is a natural radioactive gas that is a natural decay product of uranium. Uranium decays to form products, including radon, that emit a type of ionizing radiation. Radon gas is a known cause of lung cancer,
Air pollution from vehicles, industry, and power plants can raise the likelihood of developing lung cancer in exposed individuals.
When our bodies are exposed to carcinogens, free radicals are formed that try to steal electrons from other molecules in the body. These free radicals damage cells and affect their ability to function and divide normally.
Lung cancer symptoms
Cancer symptoms are quite varied and depend on where the cancer is located, where it has spread, and how big the tumor is. Lung cancer symptoms may take years before appearing, usually after the disease is in an advanced stage.
Many symptoms of lung cancer affect the chest and air passages. These include:
- Persistent or intense coughing
- Pain in the chest shoulder, or back from coughing
- Changes in color of the mucus that is coughed up from the lower airways (sputum)
- Difficulty breathing and swallowing
- Hoarseness of the voice
- Harsh sounds while breathing (stridor)
- Chronic bronchitis or pneumonia
- Coughing up blood, or blood in the sputum
- Symptoms If the lung cancer spreads, or metastasizes
- If cancer spreads to the brain, patients may experience vertigo, headaches, or seizures.
- In the liver may become enlarged and cause jaundice and bones can become painful, brittle, and broken. It is also possible for the cancer to infect the adrenal glands resulting in hormone level changes.
- Symptoms As lung cancer cells spread and use more of the body's energy,
- Fever
- Fatigue
- Unexplained weight loss
- Pain in joints or bones
- Problems with brain function and memory
- Swelling in the neck or face
- General weakness
- Bleeding and blood clots
The main lung cancer treatments are surgery, chemotherapy, and/or radiation. immunotherapy, hormone therapy, and gene therapy.
Surgery is the oldest known treatment for cancer. If a cancer is in stage I or II and has not metastasized, it is possible to completely cure a patient by surgically removing the tumor and the nearby lymph nodes. After the disease has spread, however, it is nearly impossible to remove all of the cancer cells.
Side effects Surgery - most notably pain and infection. Lung cancer surgery is an invasive procedure that can cause harm to the surrounding body parts.
Radiation treatment, also known as radiotherapy, destroys or shrinks lung cancer tumors by focusing high-energy rays on the cancer cells. This causes damage to the molecules that make up the cancer cells and leads them to commit suicide. Radiotherapy utilizes high-energy gamma-rays that are emitted from metals such as radium or high-energy x-rays that are created in a special machine. Radiation can be used as the main treatment for lung cancer, to kill remaining cells after surgery, or to kill cancer cells that have metastasized.
Early radiation treatments caused severe side-effects because the energy beams would damage normal, healthy tissue, but technologies have improved so that beams can be more accurately targeted. Radiation oncologists can focus the radiation in precise locations in the body for certain lengths of time, reducing the risk of damage to surrounding healthy tissue. Treatments occur intermittently over weeks or months depending on the size and extent of the tumor, the dosage of radiation, and how much damage is being done to noncancerous tissue.
Common side effects of radiation therapy include fatigue, nausea, and loss of appetite, hair loss, and skin affectations that cause skin to become dry, irritated, and sensitive.
Chemotherapy utilizes strong chemicals that interfere with the cell division process -damaging proteins or DNA - so that cancer cells will commit suicide. These treatments target any rapidly dividing cells (not just cancer cells), but normal cells usually can recover from any chemical-induced damage while cancer cells cannot. Chemotherapy is considered systemic because its medicines travel throughout the entire body, killing the original tumor cells as well as cancer cells that have spread throughout the body.
Combination therapies often include multiple types of chemotherapy, and chemotherapy is also given as adjuvant therapy as a complement to surgery and radiation. Adjuvant therapy is designed to reduce the risk of cancer recurrence after surgery and killing any cancer cells that exist after surgery. Chemotherapy can be given before surgery, called neo-adjuvant therapy, to shrink tumors and to make surgery more successful.
Chemotherapy carries several common side effects, but they depend on the type of chemotherapy and the health of the patient. These include nausea and vomiting, appetite loss, diarrhea, hair loss, fatigue from anemia, infections, bleeding, and mouth sores. Many of these side effects are only temporarily felt during treatment, and several drugs exist to help patients cope with the symptoms.
How to prevent lung cancer
Eliminating tobacco smoking is a primary goal in the prevention of lung cancer, and smoking cessation is an important preventive tool in this process. Policy interventions to decrease passive smoking in public areas such as restaurants and workplaces
Source and References:
http://en.m.wikipedia.org/wiki/Lung_cancer
http://www.medicalnewstoday.com/info/lung-cancer/
http://www.medicinenet.com/script/main/mobileart.asp?articlekey=406&page=1
No comments:
Post a Comment