World Cancer Day: Improve your awareness and get screened
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 and cancer treatment.
Cancer is a group of more than 100 diseases that can develop almost anywhere in the body. Cells are the basic units that make up the human body. They grow and divide to make new cells in order to allow the body to grow and replenish itself. Usually, cells die when they get too old or damaged. Then, new cells take their place. However, this is always a controlled and orderly process and the cells do not grow and divide uncontrollably.
Cancer begins when genetic changes interfere with this orderly process of cell reproduction. Cells start to grow uncontrollably. These cells may form a mass of cells that grow uncontrollably called a tumor. A tumor can be benign. This means its growth is not so uncontrollable that it could spread to other parts of the body and disturb normal physiologic processes. However, if the tumor is malignant, then it is cancerous and is likely to grow so uncontrollably that it spreads to other parts of the body and disturbs normal physiological processes. Tumors result from genetic changes in solid tissues like the brain, colon, stomach, prostate, breasts, skin etc. If the source of the genetic change is form tissue that is not solid however, e.g. blood or lymph, a tumor does not develop. These include leukemias, most types of lymphoma, and myeloma.
Doctors divide cancer into types based on where it begins. Four main types of cancer are:
Carcinomas. 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.
Sarcomas. 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.
Leukemias. Leukemia is a cancer of the blood. Leukemia begins when healthy blood cells change and grow uncontrollably. The four main types of leukemia are acute lymphocytic leukemia, chronic lymphocytic leukemia, acute myeloid leukemia, and chronic myeloid leukemia.
Lymphomas. Lymphoma is a cancer that begins in the lymphatic system. The lymphatic system is a network of vessels and glands that help fight infection. There are two main types of lymphomas: Hodgkin lymphoma and non-Hodgkin lymphoma.
There are also other types of cancers in addition to these main four types.
As a cancerous tumor grows, the bloodstream or lymphatic system may carry cancer cells to other parts of the body. During this process, the cancer cells grow and may develop into new tumors. This is known as metastasis. One of the first places a cancer often spreads is to the lymph nodes. Lymph nodes are tiny, bean-shaped organs that help fight infection. They are located in clusters in different parts of the body, such as the neck, groin area, and under the arms. Cancer may also spread through the bloodstream to distant parts of the body. These parts may include the bones, liver, lungs, or brain. Even if the cancer spreads, it is still named for the area where it began. For example, if breast cancer spreads to the lungs, it is called metastatic breast cancer, not lung cancer.
Dr. Visham Bhimull
Diploma in Family Medicine (UWI)