Cancer refers to any one of a large number of diseases characterized by the development of abnormal cells that divide uncontrollably and have the ability to infiltrate and destroy normal body tissue. Cancer often has the ability to spread throughout your body. Cancer is the second-leading cause of death in the world.
But survival rates are improving for many types of cancer, thanks to improvements in cancer screening, treatment and prevention. Make an appointment with your doctor if you have any persistent signs or symptoms that concern you. If you don't have any signs or symptoms, but are worried about your risk of cancer, discuss your concerns with your doctor. Ask about which cancer screening tests and procedures are appropriate for you.
Cancer is caused by changes mutations to the DNA within cells. The DNA inside a cell is packaged into a large number of individual genes, each of which contains a set of instructions telling the cell what functions to perform, as well as how to grow and divide. Errors in the instructions can cause the cell to stop its normal function and may allow a cell to become cancerous. These mutations are the most common ones found in cancer. But many other gene mutations can contribute to causing cancer.
Gene mutations occur frequently during normal cell growth. However, cells contain a mechanism that recognizes when a mistake occurs and repairs the mistake. Occasionally, a mistake is missed. This could cause a cell to become cancerous. The gene mutations you're born with and those that you acquire throughout your life work together to cause cancer. For instance, if you've inherited a genetic mutation that predisposes you to cancer, that doesn't mean you're certain to get cancer.
Instead, you may need one or more other gene mutations to cause cancer. Your inherited gene mutation could make you more likely than other people to develop cancer when exposed to a certain cancer-causing substance.
It's not clear just how many mutations must accumulate for cancer to form. It's likely that this varies among cancer types. While doctors have an idea of what may increase your risk of cancer, the majority of cancers occur in people who don't have any known risk factors. A doctor might order X-rays and blood tests and recommend the person go to see an oncologist say: on-KAH-luh-jist.
An oncologist is a doctor who takes care of and treats cancer patients. The oncologist will likely run other tests to find out if someone really has cancer. If so, tests can determine what kind of cancer it is and if it has spread to other parts of the body. Based on the results, the doctor will decide the best way to treat it.
One test that an oncologist or a surgeon may perform is a biopsy say: BY-op-see. During a biopsy, a piece of tissue is removed from a tumor or a place in the body where cancer is suspected, like the bone marrow. Don't worry — someone getting this test will get special medicine to keep him or her comfortable during the biopsy. The sample that's collected will be examined under a microscope for cancer cells. The sooner cancer is found and treatment begins, the better someone's chances are for a full recovery and cure.
Cancer is treated with surgery, chemotherapy, or radiation — or sometimes a combination of these treatments. The choice of treatment depends on:. Surgery is the oldest form of treatment for cancer — 3 out of every 5 people with cancer will have an operation to remove it. During surgery, the doctor tries to take out as many cancer cells as possible. Some healthy cells or tissue may also be removed to make sure that all the cancer is gone.
Chemotherapy say: kee-mo-THER-uh-pee is the use of anti-cancer medicines drugs to treat cancer. These medicines are sometimes taken as a pill, but usually are given through a special intravenous say: in-truh-VEE-nus line, also called an IV. An IV is a tiny plastic catheter straw-like tube that is put into a vein through someone's skin, usually on the arm.
The catheter is attached to a bag that holds the medicine. The medicine flows from the bag into a vein, which puts the medicine into the blood, where it can travel throughout the body and attack cancer cells. Chemotherapy is usually given over a number of weeks to months. When cells are abnormal or get old, they usually die.
Cancer starts when something goes wrong in this process and your cells keep making new cells and the old or abnormal ones don't die when they should. As the cancer cells grow out of control, they can crowd out normal cells. This makes it hard for your body to work the way it should. For many people, cancer can be treated successfully. In fact, more people than ever before lead full lives after cancer treatment.
There are many types of cancer. Cancer can develop anywhere in the body and is named for the part of the body where it started. For instance, breast cancer that starts in the breast is still called breast cancer even if it spreads metastasizes to other parts of the body. These cancers are alike in some ways, but can be different in the ways they grow, spread, and respond to treatment.
There are 2 kinds of tumours:. As our body is made up of cells, cancer can start anywhere in the body. The place where the cancer first starts is called primary cancer. This is called cancer of unknown primary. Sometimes cancer cells move to other parts of the body. Cancer can happen to anybody. Cancer is not contagious. People cannot catch cancer from someone who has it. It is safe to be near someone who has cancer.
Find out more about preventing cancer. Screening for breast , bowel and cervical cancer saves lives because cancer can be found earlier, when it is easier to treat. Sometimes, doctors find cancer because the person is feeling unwell and has symptoms.
It is important to know what is normal for your body, and to see your doctor straight away if you notice changes like:. The treatment depends on the type and stage of the cancer how much it has grown and spread.
The most common cancer treatments are:. Each person is different; some people have more than one type of treatment. If the cancer is found early, it may be easier to treat. With these types of treatment, you might feel less pain and have a better life. All cancer treatments can have side effects.
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