Cancer – What is It and How Can You Prevent It?
Cancer is a disease in which abnormal cells grow and divide without control or order, eventually crowding out and overrunning normal tissue and spreading to other parts of the body. If not treated, cancer can lead to organ failure or death.
The disease is the result of mutations (changes) in genes that normally provide instructions for how cells grow and die, repair themselves, differentiate into different types of cells, or take on specific functions such as becoming a nerve cell or a muscle cell. Mutations can be inherited or acquired — they may occur spontaneously or as a consequence of lifestyle factors such as smoking and sun exposure, or from environmental hazards such as asbestos or industrial chemicals.
Many people with cancer have no symptoms at all, and they are diagnosed only when doctors perform tests for another health issue or problem. Those who do have symptoms often report them to a doctor after noticing an unusual change in their appearance, weight or behavior.
Regardless of how they are found, most cancers start in one part of the body, called a tumor. Then, the cancerous cells can grow and spread to other areas of the body through the bloodstream or lymph nodes, which are clusters of immune cells located throughout the body.
In most cases, cancer is a chronic disease that a person will live with for a long time. But early detection and aggressive therapy can prevent the cancer from spreading or worsening and may even cure the cancer.
Some cancers are caused by inherited gene mutations, and these types of cancers can’t be prevented. But many cancers are caused by lifestyle choices and other external factors, which can be avoided or reduced.
When it comes to prevention, the best thing you can do is avoid things that are known to increase your cancer risk, such as excessive sun exposure and a diet that is high in fat, sugar, red meat and processed foods. You can also reduce your risk by eating a balanced diet and taking a standard multivitamin daily.
Scientists have learned a lot about how cancer develops and how it responds to treatment. The basic explanation is that natural selection applies to cancer just as it does to any other biological organism — the more mutations a cancer cell has, the more likely it is to survive and proliferate. In addition, a cancerous tumor can be influenced by its microenvironment and by ecological parameters such as the availability of nutrients, oxidants and space. This influences the phenotypic characteristics of cancer cells and can favor those that resist apoptosis or evade the immune system.
As the cancer continues to evolve and adapt, it shifts between levels of selection — for instance, in its microenvironment it can develop adaptations that allow it to better uptake resources, co-opt normal cells such as fibroblasts, evade the immune system or produce public goods such as angiogenesis and aspects of the extracellular matrix, allowing it to grow and spread.
Cancer is a disease in which abnormal cells grow and divide without control or order, eventually crowding out and overrunning normal tissue and spreading to other parts of the body. If not treated, cancer can lead to organ failure or death. The disease is the result of mutations (changes) in genes that normally provide instructions for how cells grow and die, repair themselves, differentiate into different types of cells, or take on specific functions such as becoming a nerve cell or a muscle cell. Mutations can be inherited or acquired — they may occur spontaneously or as a consequence of lifestyle factors such as smoking and sun exposure, or from environmental hazards such as asbestos or industrial chemicals. Many people with cancer have no symptoms at all, and they are diagnosed only when doctors perform tests for another health issue or problem. Those who do have symptoms often report them to a doctor after noticing an unusual change in their appearance, weight or behavior. Regardless of how they are found, most cancers start in one part of the body, called a tumor. Then, the cancerous cells can grow and spread to other areas of the body through the bloodstream or lymph nodes, which are clusters of immune cells located throughout the body. In most cases, cancer is a chronic disease that a person will live with for a long time. But early detection and aggressive therapy can prevent the cancer from spreading or worsening and may even cure the cancer. Some cancers are caused by inherited gene mutations, and these types of cancers can’t be prevented. But many cancers are caused by lifestyle choices and other external factors, which can be avoided or reduced. When it comes to prevention, the best thing you can do is avoid things that are known to increase your cancer risk, such as excessive sun exposure and a diet that is high in fat, sugar, red meat and processed foods. You can also reduce your risk by eating a balanced diet and taking a standard multivitamin daily. Scientists have learned a lot about how cancer develops and how it responds to treatment. The basic explanation is that natural selection applies to cancer just as it does to any other biological organism — the more mutations a cancer cell has, the more likely it is to survive and proliferate. In addition, a cancerous tumor can be influenced by its microenvironment and by ecological parameters such as the availability of nutrients, oxidants and space. This influences the phenotypic characteristics of cancer cells and can favor those that resist apoptosis or evade the immune system. As the cancer continues to evolve and adapt, it shifts between levels of selection — for instance, in its microenvironment it can develop adaptations that allow it to better uptake resources, co-opt normal cells such as fibroblasts, evade the immune system or produce public goods such as angiogenesis and aspects of the extracellular matrix, allowing it to grow and spread.