Cancer Overview
Cancer is a word that brings fear to the heart of all who hear it, especially when mentioned by a doctor in relation to recent tests. So what is cancer? What causes it? Why is it so dangerous to our health?
Before we can answer these questions, we need to consider the basics.
Microscopic cells are the basic building blocks of animals and plants. Our bodies are composed of millions of tiny cells of various types. Normally, our cells grow and divide to produce more cells as needed to keep the body healthy and functioning properly. However, for a variety of reasons, things can occasionally go wrong with our cells.
Each of our cells contains tiny strands of deoxyribonucleic acid (DNA), and these molecules carry genetic information and pass it from one generation to the next. It is this DNA that determines the type and function of each cell.
A mutation is a change in the DNA makeup of a living cell. Mutations are often caused by mistakes or problems arising during cell division. Other problems can arise when exposed to DNA-damaging substances or agents in the environment. Exposure to radiation, carcinogenic substances, and smoking are all known to cause mutations in cells in mammals and these mutations can give rise to life threatening diseases.
Mutations can be damaging, advantageous, or have no effect whatsoever. If mutations occur in cells making eggs or sperm, they can be passed onto future generations and inherited by their offspring. If the mutations occur in other types of cells, then they are not always inherited or passed on to future generations. Specific mutations may lead to cancer or other diseases.
A Tumour is an abnormal mass of tissue that results when cells divide more than they should or do not die when they should. Tumours may be benign (not cancerous), or malignant (cancerous).
Benign tumours are usually fairly harmless, and they usually don't spread around the body or cause any damage to other organs. They are usually fairly easy to remove, for example with surgery, and they often don't grow back. Benign tumours are rarely a threat to life. Benign tumours are not cancer. However, on occasion benign tumours can change and become malignant. Malignant tumours are cancer, and they can have serious effects on health and life-span.
Cancer is a particular type of disease in which abnormal body cells are formed and proliferate so they can attack nearby tissues and organs of the body. They then spread through the bloodstream and lymphatic system to other parts of the body and invade other organs and tissues.
The human body can be affected by a wide range of cancers. However, there are really only five main types of cancer: Carcinoma, Sarcoma, Leukaemia, Lymphoma, and Multiple Myeloma.
Carcinoma is a type of cancer beginning in the skin and/or tissues lining and covering our internal organs.
Sarcoma is a type of cancer that begins in our bones, cartilage, fat, muscle, blood vessels, or other connective or supportive type tissue.
Leukaemia is a type of cancer that starts within the blood-forming tissues for example the bone marrow. This causes huge numbers of abnormal blood cells to be produced and enter the bloodstream.
Lymphoma and Multiple Myeloma are both types of cancer that begin in the cells of the immune system.
Metastasis is the spread of cancer from one part of the body to another. Cells from the cancer can break away from the original tumour and spread to other parts of the body via the bloodstream or lymphatic system, lodging in other organs and tissues and allowing the cancer to develop and grow in these places.
A tumour formed by cells that have spread is called a metastatic tumour. A metastatic tumour contains cells that are like those in the original (primary) tumour. Once a tumour spreads throughout the body, it can become particularly difficult to control, treat, and eradicate.
Lung Cancer - Overview
Lung Cancer is a type of cancer that forms in tissues of the lung, usually in the cells lining air passages. Many lung cancers begin in the bronchi though others can start in other parts of the lungs. Lung cancer also has a tendency to form in the glands below the bronchi.
Lung Cancer - Probabilities
Lung cancer causes up to 30% of all cancer related deaths, and it is the 2nd leading cause of death among both men and women in western society. 85% of all lung cancers are caused by a person's smoking habit or just by breathing in the second-hand smoke of others.
Lung Cancer - Screening
At this moment in time, there is no particularly useful single test that can be considered 100% reliable for the early detection of lung cancer. Unfortunately unless someone is undergoing a health screen for something completely unrelated, lung cancer is very often only discovered in the later stages of the disease when it is often too late to do anything but offer palliative treatment.
Lung Cancer - Symptoms
The most common indicators and symptoms of lung cancer include the following: Fatigue Shortness of breath and wheezing (dyspnoea) A cough that doesn't go away and gets worse over time Repeated problems with pneumonia or bronchitis Constant chest pain Coughing up blood (bloody sputum) (haemoptysis) Swelling of the neck and face Fever Loss of appetite and Weight loss (anorexia) Hoarse voice
Lung Cancer Treatment Options - Radiation
In many cases of lung cancer, surgery is not an option. This may be because of the advanced stage of the cancer, the location of the tumor or tumors, or because of the overall general health of the patient. In those cases, the oncologist may suggest radiation therapy to treat lung cancer. Even if surgery is an option, the doctor may suggest irradiation either before therapy to shrink the tumor or after surgery to destroy any remaining cancer cells.
Lung Cancer - Trends by Ethnicity, Sex and Race
In the USA and many other western countries, lung cancer is the leading cause of cancer death. Lung cancer has been found to be the leading cancer killer among Caucasians, African-Americans, Asians and Hispanic males.