| Medical Dictionary |
A Medical Dictionary of Medical Terminology
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Cancer is not just one disease but many diseases. Cancer begins in your cells, which are the building blocks of your body. Usually, your body forms new cells as needed, replacing old cells that die. Sometimes this process goes wrong. New cells grow even when you don't need them, and old cells don't die when they should. These extra cells can form a mass called a tumor.
Tumors can be benign or malignant. Benign tumors aren't cancer, while malignant ones are. Cells from malignant tumors can invade nearby tissues. They can also break away and spread to other parts of your body. The spread of cancer from one part of the body to another is called metastasis. Symptoms and treatment depend on the type of cancer and how advanced it is.
What are the types of cancer?There are more than 100 different types of cancer. Cancer can start almost anywhere in your body. Most cancers are named for where they start. For example, lung cancer starts in the lung, and breast cancer starts in the breast.
Cancer may also be described by the type of cell that formed it, such as sarcoma if cancer begins in your bone and soft tissue. Carcinoma is the most common type of cancer. It is formed by epithelial cells, the cells that cover the inside and outside surfaces of your body.
How does cancer develop?Cancer is a genetic disease. That means changes in your genes cause it. Changes in your genes are also called gene variants or mutations. Genes are parts of DNA in your cells that you inherit from your parents. However, only some cancers are caused by genes passed down from your parents.
Genetic changes can occur to your genes over your lifetime that affect how your cells function. Usually, your body gets rid of damaged cells before they turn cancerous, but this ability goes down as you age. Other factors that may affect your risk of developing cancer can include:
Cancer symptoms depend on the type of cancer. For example, some of the symptoms that cancer may cause can include:
Cancer may cause various symptoms but often doesn't cause pain. Don't wait until you're having pain before seeing your health care provider. See your provider if you have symptoms that don't get better in a few weeks.
How is cancer diagnosed?There is no single test that can diagnose cancer. The tests ordered are usually based on your symptoms. Your provider may:
To find out if you have cancer, your provider may order a biopsy. A biopsy is the procedure of removing and examining tissue, cells, or fluids from your body.
What are the treatments for cancer?Treatment depends on the type of cancer and how advanced it is. Most treatment plans may include surgery, radiation, and/or chemotherapy. Some may involve hormone therapy, immunotherapy or other types of biological therapy, or stem cell transplantation.
Can cancer be prevented?It's usually not possible to know exactly why cancer develops in some people but not others. There are some things that you can't control which may increase or decrease your risk of getting cancer, such as inheriting certain genes or your age. But some lifestyle habits may increase your risk of certain types of cancer. Avoid or reduce lifestyle habits such as:
NIH: National Cancer Institute
The lymphatic system is a network of tissues and organs. It is made up of:
Your bone marrow and thymus produce the cells in lymph. They are part of the system, too.
The lymphatic system clears away infection and keeps your body fluids in balance. If it's not working properly, fluid builds in your tissues and causes swelling, called lymphedema. Other lymphatic system problems can include infections, blockage, and cancer.
Lymphoma is a cancer of a part of the immune system called the lymph system. There are many types of lymphoma. One type is Hodgkin disease. The rest are called non-Hodgkin lymphomas.
Non-Hodgkin lymphomas begin when a type of white blood cell, called a T cell or B cell, becomes abnormal. The cell divides again and again, making more and more abnormal cells. These abnormal cells can spread to almost any other part of the body. Most of the time, doctors don't know why a person gets non-Hodgkin lymphoma. You are at increased risk if you have a weakened immune system or have certain types of infections.
Non-Hodgkin lymphoma can cause many symptoms, such as :
Your doctor will diagnose lymphoma with a physical exam, blood tests, a chest x-ray, and a biopsy. Treatments include chemotherapy, radiation therapy, targeted therapy, biological therapy, or therapy to remove proteins from the blood. Targeted therapy uses drugs or other substances that attack specific cancer cells with less harm to normal cells. Biologic therapy boosts your body's own ability to fight cancer. If you don't have symptoms, you may not need treatment right away. This is called watchful waiting.
NIH: National Cancer Institute
X-rays are a painless medical imaging test. They send a small amount of radiation through your body to create pictures of bones and organs.
X-rays are a type of electromagnetic radiation. They create images in shades of black, white, and gray because different tissues absorb radiation differently. Bones absorb the most radiation and appear white. Fat and other soft tissues absorb less and appear gray. Air absorbs the least radiation, so areas like the lungs appear black.
The image is recorded on film or sent to a computer. Health care providers use x-rays to find health problems and to check how well certain treatments are working.
Who needs an x-ray?X-rays are commonly used to check for fractures (broken bones). They are also used for other purposes. For example, chest x-rays can detect pneumonia. Mammograms use x-rays to look for breast cancer. X-rays are also used as part of other imaging tests, such as CT scans.
How do you prepare for an x-ray?In most cases, little or no preparation is needed. You may be asked to wear a lead apron to protect certain parts of your body. You may also be asked to remove jewelry or other items that could affect the image.
The amount of radiation from an x-ray is small. For example, the radiation from a chest x-ray is about the same as the natural radiation you are exposed to from the environment over about 10 days.
Always tell your provider if you are pregnant or think you may be pregnant.
How is an x-ray done?Depending on the part of your body being examined, you may be asked to stand, sit, or lie down. You will need to stay still for a short time while the image is taken.
What should you expect after an x-ray?After an x-ray, you can return to normal activities right away. A specialist called a radiologist reviews the images and shares the results with your provider.