Cancer – A Serious Disease That Affects People All Over the World
Cancer is the uncontrolled growth of abnormal cells that invade and destroy normal body tissues. It is an extremely serious disease that affects not only the person who has it, but also his or her family and friends. Almost everyone knows someone who has had cancer or is affected by it. Cancer is the most common cause of death worldwide; it kills more people than infectious diseases such as tuberculosis and pneumonia.
Cancer starts when a cell in the body develops mutations (mistakes) in its genetic makeup. Normally, when a cell is damaged or changed in some way, the mechanism that controls its growth and repair recognizes and repairs the damage. But when this process fails, a new, abnormal cell is formed that cannot be controlled and that can continue to grow without control.
The first steps in diagnosing cancer usually include a physical exam and reviewing a person’s medical history, especially a detailed account of symptoms. The medical caregiver may then order certain tests to check for and diagnose cancer.
Most of the time, a person with cancer is diagnosed after a health care professional has noticed a lump or unusual growth in the skin. But sometimes cancer is found by chance during routine screening examinations, such as a mammogram or colonoscopy.
A variety of factors can lead to cancer, including exposure to toxins and radiation. But more than half of all cancers are attributed to gene mutations. These mutations can be inherited from one’s parents or they can occur over a lifetime.
Often, the mutations that cause cancer begin in the stem cells that are responsible for producing different types of specialized cells needed throughout the body. But they can also start in other cells, such as epithelial cells that line the body cavity and cover its surface. In children, most cancers are inherited; in adults, they usually result from environmental exposure over time.
In addition, cancer cells that have accumulated mutations that confer a survival advantage may have an advantage over surrounding, non-cancerous cells, in competition for limited resources, such as space and nutrients. These cancer cells then spread to other parts of the body, forming more tumors and potentially killing the host.
Cancer can be treated in many ways, depending on the type of cancer and its location in the body. The most common treatments are surgery, chemotherapy, and radiation therapy. Other treatments include hormone therapy to reduce the production of cancer-causing substances by the ovaries and testicles, and targeted drugs that are designed to target specific features of cancer cells. These drugs can prevent blood vessels from growing around cancer cells, stop them from dividing, or make them die. Other therapies, such as hyperthermia, use heat to kill cancer cells without harming normal ones.
Cancer is the uncontrolled growth of abnormal cells that invade and destroy normal body tissues. It is an extremely serious disease that affects not only the person who has it, but also his or her family and friends. Almost everyone knows someone who has had cancer or is affected by it. Cancer is the most common cause of death worldwide; it kills more people than infectious diseases such as tuberculosis and pneumonia. Cancer starts when a cell in the body develops mutations (mistakes) in its genetic makeup. Normally, when a cell is damaged or changed in some way, the mechanism that controls its growth and repair recognizes and repairs the damage. But when this process fails, a new, abnormal cell is formed that cannot be controlled and that can continue to grow without control. The first steps in diagnosing cancer usually include a physical exam and reviewing a person’s medical history, especially a detailed account of symptoms. The medical caregiver may then order certain tests to check for and diagnose cancer. Most of the time, a person with cancer is diagnosed after a health care professional has noticed a lump or unusual growth in the skin. But sometimes cancer is found by chance during routine screening examinations, such as a mammogram or colonoscopy. A variety of factors can lead to cancer, including exposure to toxins and radiation. But more than half of all cancers are attributed to gene mutations. These mutations can be inherited from one’s parents or they can occur over a lifetime. Often, the mutations that cause cancer begin in the stem cells that are responsible for producing different types of specialized cells needed throughout the body. But they can also start in other cells, such as epithelial cells that line the body cavity and cover its surface. In children, most cancers are inherited; in adults, they usually result from environmental exposure over time. In addition, cancer cells that have accumulated mutations that confer a survival advantage may have an advantage over surrounding, non-cancerous cells, in competition for limited resources, such as space and nutrients. These cancer cells then spread to other parts of the body, forming more tumors and potentially killing the host. Cancer can be treated in many ways, depending on the type of cancer and its location in the body. The most common treatments are surgery, chemotherapy, and radiation therapy. Other treatments include hormone therapy to reduce the production of cancer-causing substances by the ovaries and testicles, and targeted drugs that are designed to target specific features of cancer cells. These drugs can prevent blood vessels from growing around cancer cells, stop them from dividing, or make them die. Other therapies, such as hyperthermia, use heat to kill cancer cells without harming normal ones.