Cancer affects 1 in 3 people in the United States. Chances are that you or someone you know has been affected by cancer. Here is some information to help you better understand what cancer is. You are made up of trillions of cells that over your lifetime normally grow and divide as needed. 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. Cells grow and divide to make new cells as the body needs them. Usually, cells die when they get too old or damaged.
Then, new cells take their place. Cancer begins when genetic changes interfere with this orderly process. Cells start to grow uncontrollably. These cells may form a mass called a tumor. A tumor can be cancerous or benign. A cancerous tumor is malignant, meaning it can grow and spread to other parts of the body.
A benign tumor means the tumor can grow but will not spread. Some types of cancer do not form a tumor. These include leukemias, most types of lymphoma, and myeloma. A carcinoma begins in the skin or the tissue that covers the surface of internal organs and glands.
Carcinomas usually form solid tumors. They are the most common type of cancer. Examples of carcinomas include prostate cancer , breast cancer , lung cancer , and colorectal cancer. A sarcoma begins in the tissues that support and connect the body. A sarcoma can develop in fat, muscles, nerves, tendons, joints, blood vessels, lymph vessels, cartilage, or bone. Leukemia is a cancer of the blood. Leukemia begins when healthy blood cells change and grow uncontrollably.
The 4 main types of leukemia are acute lymphocytic leukemia , chronic lymphocytic leukemia , acute myeloid leukemia , and chronic myeloid leukemia. Lymphoma is a cancer that begins in the lymphatic system. Lymphoma is cancer that starts in the lymph glands or cells of the lymphatic system. The lymphatic system runs all through the body so lymphoma can start just about anywhere. It happens because some of the lymphatic system white blood cells lymphocytes start to divide in an abnormal way.
And don't die as they should. These cells start to divide before they become fully grown mature so they can't fight infection. The abnormal lymphocytes start to collect in the lymph nodes or other places such as the bone marrow or spleen. They can then grow into tumours. You can find out about lymphomas. Myeloma is a cancer that starts in plasma cells.
Plasma cells are a type of white blood cell made in the bone marrow. They produce antibodies, also called immunoglobulins, to help fight infection.
Plasma cells can become abnormal and multiply out of control. They make a type of antibody that doesn't work properly to fight infection. Cancer can start in the cells of the brain or spinal cord. The brain controls the body by sending electrical messages along nerve fibres.
The fibres run out of the brain and join together to make the spinal cord, which also takes messages from the body to the brain. The brain and spinal cord form the central nervous system.
The brain is made up of billions of nerve cells called neurones. It also contains special connective tissue cells called glial cells that support the nerve cells. The most common type of brain tumour develops from glial cells. It is called glioma. Some tumours that start in the brain or spinal cord are non cancerous benign and grow very slowly.
Others are cancerous and tend to grow and spread.
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