Cancer is a group of diseases in which abnormal cells grow uncontrollably and spread to other parts of the body. This can affect any organ or tissue. It is one of the leading causes of death in the United States and worldwide.
The cause of cancer is unknown, although many factors have been linked to the development of this disease. These include genetics, environmental factors, and the way your body responds to stress or damage.
Every cell in your body has a specific piece of DNA, called your DNA, that contains instructions about how to grow and divide. This information is replicated by your cells, but mistakes (mutations) can occur. Normally, your DNA prevents these errors from harming the cell. But sometimes, these errors can be passed from one cell to another and cause the cells to grow out of control.
These mutations can also change the cells’ ability to get energy from nutrients, making them more likely to grow quickly. They can also lead to problems with your immune system, which defends your body against infection.
Some of these changes can be inherited, but others can develop through normal life events like the birth of children or exposure to certain types of pollution. Researchers are studying all these factors to learn how they can be changed and prevented from happening to people.
The most common forms of cancer are breast cancer and prostate cancer. But other types of cancer also can happen, such as skin cancer and lung cancer.
Your health care team will tell you about what can be done to help you avoid or treat cancer. This can include stopping smoking, eating healthy, exercising regularly, and getting regular screenings. It can also include reducing your exposure to things that can increase your risk for some types of cancer, such as indoor and outdoor air pollution from fires, mold and radon.
Often, your doctor will use a number of different tests to determine what stage your cancer is in. This can include a test to see how fast it is growing or how much it has spread, such as a biopsy, blood tests and CT scans.
Most cancers have a low risk of spreading to other parts of the body. But some types of cancer can spread to the lymph nodes, lungs, or other parts of the body.
In some cases, your doctor may ask you to have a biopsy, which is when doctors take a sample of tissue from your cancer to examine it under a microscope. They look for certain kinds of changes in your cells, such as a difference in the number or size of chromosomes.
These changes may indicate that your cancer is in an early stage. This is referred to as “stage 0.”
Then, your doctor may recommend that you undergo treatment. Depending on your diagnosis, this can include surgery or radiation therapy.
Getting diagnosed and treated early is important for surviving your cancer and living a longer, healthier life. This is why the National Cancer Institute has been working to reduce cancer mortality by preventing it and providing better care for patients who have it.