How do healthy people get cancer

These types of triggers act on the body slowly over time, so the cancers that may result from them don't show up until a person is an adult. That's one reason why teens don't get the same types of cancers as adults do.

Doctors do know for sure that cancer itself is not contagious, so you don't have to worry about catching it from someone else or spreading it to another person although people with certain infectious diseases such as AIDS or hepatitis are more vulnerable to certain cancers.

Cancer is also never a person's fault. It's simply not true that a person may have done something wrong to get the disease. The first sign of cancer is a symptom — a signal that something is wrong. There are many different signs that a person may have cancer, just as there are many different forms of the disease. A few of the more common symptoms of cancer include:. Only you know how your body works and what you feel like when you're healthy.

If you haven't been feeling well, it's best to tell an adult who can make sure you see a doctor who will evaluate your symptoms. Cancer, like most illnesses, is easier to treat when it's found early, so when in doubt, check it out. When cancer is suspected, doctors will order various tests. These might include blood tests , in which blood cells are examined under a microscope for problems, X-rays , or an MRI , a test that can be used to detect tumors.

A doctor who specializes in treating people with cancer is called an oncologist pronounced: ahn-KOL-uh-jist. They often use a biopsy pronounced: BYE-op-see to diagnose cancer. In this procedure, a doctor removes a small tissue sample to examine it for cancer cells. Most cancers can be treated, especially the types of cancers teens are likely to get. The number of people who beat cancer goes up every year because of new cancer treatments. The three common methods for treating cancer are: surgery, chemotherapy, and radiation.

Because cancer is different in each patient, each person's treatment plan will be individually designed for him or her. Someone with cancer may undergo any one of these treatments or a combination of them. Surgery removes cancerous tissue. Depending on the location of the cancer, surgery can be simple or complex, so the operation may be an outpatient procedure where someone is in and out of the hospital on the same day or may require that the person stay in the hospital.

Generally, the surgeon removes the cancerous tissue along with a small amount of the healthy tissue surrounding it to make sure that all the cancer is removed and has not spread. The treatment of cancer using medication is called chemotherapy. For example, a woman whose mother had breast cancer is at least twice as likely to have breast cancer than a woman who does not have the same family history.

Some women have strong family histories or genetic mutations linked to breast cancer. Since they are at a very high risk of breast cancer, they may choose to remove their breasts to prevent cancer.

Also, these women may choose to take medicine to lower the risk of breast cancer. People with a strong family history of cancer may consider genetic testing. Your doctor or genetic counselor can talk with you about getting certain genetic tests. They can tell you your risk of getting cancer based on your family history and other risk factors. Doctors use absolute risk and relative risk to assess if a person's risk is higher or lower than that of either the general population or a certain group of people.

Absolute risk is the chance that a person will develop a disease during a given time. This identifies how many people are at risk for a disease in the general population. It cannot identify the risk for a certain person or group of people.

For example, absolute risk cannot show if a group of older women has a higher risk of breast cancer than a group of younger women. Relative risk compares the risk of disease between two groups of people.

For instance, imagine you are comparing the risk of breast cancer among 2 groups of women. But only the women in 1 group have a certain risk factor for breast cancer. The other group of women does not have this risk factor. Researchers keep track of how many people from each group develop cancer over a certain time. But only 1 woman without this risk factor gets cancer. Then those in the first group have 2 times the risk of the second group. Patients can use risk measurements to make better choices about lifestyle changes or cancer screening.

It is also important to know the difference between absolute and relative risk. For instance, the relative risk in the last example might sound high. But look at the absolute risk to get a more complete picture. Errors in the instructions can cause the cell to stop its normal function and may allow a cell to become cancerous.

These mutations are the most common ones found in cancer. But many other gene mutations can contribute to causing cancer. Gene mutations occur frequently during normal cell growth. However, cells contain a mechanism that recognizes when a mistake occurs and repairs the mistake.

Occasionally, a mistake is missed. This could cause a cell to become cancerous. The gene mutations you're born with and those that you acquire throughout your life work together to cause cancer. For instance, if you've inherited a genetic mutation that predisposes you to cancer, that doesn't mean you're certain to get cancer. Instead, you may need one or more other gene mutations to cause cancer. Your inherited gene mutation could make you more likely than other people to develop cancer when exposed to a certain cancer-causing substance.

It's not clear just how many mutations must accumulate for cancer to form. It's likely that this varies among cancer types. While doctors have an idea of what may increase your risk of cancer, the majority of cancers occur in people who don't have any known risk factors. Factors known to increase your risk of cancer include:. Cancer can take decades to develop. That's why most people diagnosed with cancer are 65 or older. While it's more common in older adults, cancer isn't exclusively an adult disease — cancer can be diagnosed at any age.

Certain lifestyle choices are known to increase your risk of cancer. Smoking, drinking more than one drink a day for women and up to two drinks a day for men, excessive exposure to the sun or frequent blistering sunburns, being obese, and having unsafe sex can contribute to cancer. You can change these habits to lower your risk of cancer — though some habits are easier to change than others.

Only a small portion of cancers are due to an inherited condition. If cancer is common in your family, it's possible that mutations are being passed from one generation to the next. You might be a candidate for genetic testing to see whether you have inherited mutations that might increase your risk of certain cancers. Keep in mind that having an inherited genetic mutation doesn't necessarily mean you'll get cancer. Some chronic health conditions, such as ulcerative colitis, can markedly increase your risk of developing certain cancers.

Talk to your doctor about your risk. The environment around you may contain harmful chemicals that can increase your risk of cancer. Even if you don't smoke, you might inhale secondhand smoke if you go where people are smoking or if you live with someone who smokes. Chemicals in your home or workplace, such as asbestos and benzene, also are associated with an increased risk of cancer. Cancer care at Mayo Clinic.