What is Cancer?
What is cancer? Cancer is a term that refers to a collection of related diseases, in which some of the body’s cells divide uncontrollably. Cancer can start almost anywhere in the body because the body is made up of trillions of cells. Normal cells divide to form new cells when the body needs them and die when they grow old or become damaged to allow new cells to take their place. However, when cancer develops, this process is not followed. As cells become abnormal, instead of dying, they continuously divide and form growths, which are called tumors.
Benign vs. Malignant Tumors Malignant cancerous tumors spread into, or invade, nearby tissues. As these tumors grow, some cancer cells can break off and travel to distant places in the body through the blood or the lymph system and form new tumors far from the original tumor. On the other hand, benign tumors do not spread into, or invade, nearby tissues. However, benign tumors can sometimes be quite large. When removed, they usually don’t grow back, whereas malignant tumors sometimes do.
Causes of Cancer Cancer is caused by genetic changes, or mutations, to the DNA within cells. Genetic mutations can allow healthy cells to grow and divide rapidly, can allow the cells to lose the controls (tumor suppressor genes) that tell these cells when to stop growing and dividing, and can prevent cells from correctly editing and repairing errors in a cell’s DNA during DNA replication. Genetic mutations can be caused by smoking, radiation, viruses, cancer-causing chemicals, obesity, hormones, chronic inflammation, and a lack of exercise.
Symptoms Signs of symptoms that can be associated with cancer, but are not specific to cancer, include fatigue, a lump or an area of thickening that can be felt under the skin, persistent cough, trouble breathing, difficulty swallowing, persistent indigestion, and unexplained bleeding or bruising.
Treatments Common treatments for cancer involve a combination of radiation therapy, surgery, chemotherapy, and targeted therapy. Radiation therapy involves using ionizing radiation to control or kill malignant cancer cells. Ionizing radiation works by damaging the DNA of cancerous cells, which leads to cellular death. Chemotherapy involves using anti-cancer drugs, which are also called chemotherapeutic agents. These drugs are intracellular poisons that inhibit cell division or cause DNA damage, which also leads to cellular death. Targeted therapy blocks the growth of cancerous cells by interfering with specific targeted molecules needed for the formation of cancer (carcinogenesis) and tumor growth, instead of interfering with all rapidly dividing cells as in traditional chemotherapy.
Reducing the Risk of Cancer People can reduce the risk of cancer by not smoking, maintaining a healthy weight, limiting alcohol intake, vaccinating against certain diseases, limiting consumption of processed meat and red meat, eating plenty of healthy foods (vegetables, fruits, whole grains), and limiting exposure to direct sunlight.
BY: Richa Kuklani Sources: ● https://www.mayoclinic.org/diseases-conditions/cancer/symptoms-causes/syc-20370588 ● https://www.cancer.gov/about-cancer/understanding/what-is-cancer ● https://en.wikipedia.org/wiki/Cancer ● https://www.medicinenet.com/cancer/article.htm