What Causes Cancer?
Cancer is a disease that begins when normal cells grow out of control and start to form new, abnormal cells. These cancer cells can grow into and spread to other parts of the body, where they can cause symptoms. There are many different types of cancer, and they can begin in any type of cell in the body. Some types of cancer are easier to treat than others. Doctors use a system called staging to describe how far the cancer has grown and how likely it is to spread.
A cancer starts when genes that manage the way a cell grows or repairs itself mutate. These mutations can happen for a variety of reasons. Sometimes they are inherited from our parents. Other times, they can be triggered by chemicals or other things in the environment. These triggers are called carcinogens. For example, the radiation from X-rays or the chemicals in cigarettes can lead to mutations that increase your risk of getting cancer. These mutations can also happen when a cell is damaged by some other factor, such as too much sunlight or an infection.
When the genetic mutations that cause cancer first occur, they are usually harmless. But over time, they can build up and change the shape and structure of a cell. This process is called clonal evolution. It is similar to the natural selection that occurs when organisms evolve by filling ecological niches. Cancer cells can exploit this feature of clonal evolution to gain more and more mutations that help them survive, grow, and spread.
The more a cancer cell mutates, the more it changes and the faster it grows. Some mutations can make a cancer cell more resistant to chemotherapy and other treatments. Other mutations can cause the cell to grow more quickly or to divide without stopping. As the cancer grows, it can form a lump that doctors call a tumor. Some tumors are made of solid tissue, while other are more liquid, like blood or pus. Cancers can also grow into and destroy the tissue around them.
Some cancers grow slowly, and they are harder to treat than other cancers that grow more rapidly. Doctors can often tell if cancer is growing in a person’s body by the symptoms they have and where the tumor is located. Some types of cancer are more likely to grow in specific areas of the body, such as the lungs or breasts.
Whether or not you have cancer, there are steps you can take to reduce your risk of getting it in the future. These steps include:
Limit your intake of red meat and processed meats (foods like hot dogs, sausage, and luncheon meat). Eat lots of vegetables, fruits, whole grains, and healthy fats, such as olive oil and nuts. Get enough exercise. Being physically active may help prevent some cancers. Talk to your doctor about getting regular screenings for cancer. These screenings might include a physical exam, blood tests, imaging tests, such as a CT scan or MRI, and biopsies.
Cancer is a disease that begins when normal cells grow out of control and start to form new, abnormal cells. These cancer cells can grow into and spread to other parts of the body, where they can cause symptoms. There are many different types of cancer, and they can begin in any type of cell in the body. Some types of cancer are easier to treat than others. Doctors use a system called staging to describe how far the cancer has grown and how likely it is to spread. A cancer starts when genes that manage the way a cell grows or repairs itself mutate. These mutations can happen for a variety of reasons. Sometimes they are inherited from our parents. Other times, they can be triggered by chemicals or other things in the environment. These triggers are called carcinogens. For example, the radiation from X-rays or the chemicals in cigarettes can lead to mutations that increase your risk of getting cancer. These mutations can also happen when a cell is damaged by some other factor, such as too much sunlight or an infection. When the genetic mutations that cause cancer first occur, they are usually harmless. But over time, they can build up and change the shape and structure of a cell. This process is called clonal evolution. It is similar to the natural selection that occurs when organisms evolve by filling ecological niches. Cancer cells can exploit this feature of clonal evolution to gain more and more mutations that help them survive, grow, and spread. The more a cancer cell mutates, the more it changes and the faster it grows. Some mutations can make a cancer cell more resistant to chemotherapy and other treatments. Other mutations can cause the cell to grow more quickly or to divide without stopping. As the cancer grows, it can form a lump that doctors call a tumor. Some tumors are made of solid tissue, while other are more liquid, like blood or pus. Cancers can also grow into and destroy the tissue around them. Some cancers grow slowly, and they are harder to treat than other cancers that grow more rapidly. Doctors can often tell if cancer is growing in a person’s body by the symptoms they have and where the tumor is located. Some types of cancer are more likely to grow in specific areas of the body, such as the lungs or breasts. Whether or not you have cancer, there are steps you can take to reduce your risk of getting it in the future. These steps include: Limit your intake of red meat and processed meats (foods like hot dogs, sausage, and luncheon meat). Eat lots of vegetables, fruits, whole grains, and healthy fats, such as olive oil and nuts. Get enough exercise. Being physically active may help prevent some cancers. Talk to your doctor about getting regular screenings for cancer. These screenings might include a physical exam, blood tests, imaging tests, such as a CT scan or MRI, and biopsies.