What to Know About Cancer Screening
When Should You Schedule Cancer Screenings?
The best time to find cancer is before symptoms appear as, in the earliest stages, many types of cancer are easier to treat and cure. When you should start getting screened for cancer depends on your risk level and the type of cancer in question. Screening isn't recommended for all forms of cancer but can be beneficial for breast, cervical, colon, and lung cancers1.
Breast cancer is easiest to treat in the earliest of stages before it has had a chance to grow or spread to other areas of the body. A mammogram can often detect the earliest stages of breast cancer before a tumor can be felt in the breast and before it starts to cause symptoms.
Colon cancer screening looks for precancerous polyps, or growths, in the colon or rectum. Early detection of the growths allows a doctor to remove them before they can develop into cancer.
If you don't have a history of colorectal cancer in your family and don't have other factors that increase your risk for cancer, you can start screening at age 45. If you're in a higher-risk group, you might need to begin screening at a younger age5.
Screening tests include a colonoscopy, which uses a small camera to look inside the colon for growths. Less invasive tests involve taking a stool sample and testing it for signs of cancer, such as changes in DNA.
Each testing option has its benefits and drawbacks. Talk to your doctor to decide which one is best for you.
A low-dose CT scan can help detect lung cancer in the early stages. Unlike other screening tests, lung cancer screening is only recommended for people who have a high risk of developing lung cancer6.
Usually, lung cancer screening is recommended for people between the ages of 50 and 80 who are current smokers, quit within the past 15 years, or who have a 20 pack-year history of smoking.
There's some disagreement about the best time to begin mammogram screening. The Centers for Disease Control and Prevention (CDC) recommends every-other-year screenings for women between the ages of 50 and 742. The American Cancer Society recommends annual screenings for women between starting at age 453. Both advise that women above age 40 follow their doctor's guidance.
If you're above the age of 40 or have a higher-than-average risk of breast cancer due to family history, talk to your doctor about when to begin screening.
Like breast cancer, a person has greater odds of beating cervical cancer if it's caught in the earliest stages. Two screening tests help to detect cervical cancer.
One is a Pap test, which detects changes in the cells of the cervix which could be a sign of cancer. The other is an HPV test, which looks for the human papillomavirus, a cause of cervical (and other types of) cancer.
Whether you need one or both tests depends on your age and risk factors. It's usually recommended that people with a cervix start getting Pap tests in their 20s4. If the results are normal, the test can be repeated every three years.
People aged 30 and above can get an HPV test and a Pap test or a Pap test on its own or an HPV test on its own. Whether co-testing or just one or the other is right for you is something to discuss with your doctor. HPV tests should be performed every five years and a Pap test every three years, provided results are normal.
A "pack-year" means smoking an average of one pack a day for a year. Someone who smokes one pack a day for 20 years has a 20 pack-year smoking history, as does someone who smokes two packs a day for 10 years.
If you are at the right age or have certain risk factors for cancer and haven't yet started screening, talk to your doctor about your options.
1. Screening Tests, Centers for Disease Control and Prevention, https://www.cdc.gov/cancer/dcpc/prevention/screening.htm
2. What is Breast Cancer Screening, CDC, https://www.cdc.gov/cancer/breast/basic_info/screening.htm
3. Cancer Screening Guidelines by Age, American Cancer Society, https://www.cancer.org/healthy/find-cancer-early/screening-recommendations-by-age.html
4. Cervical Cancer: What Should I Know About Screening?, CDC, https://www.cdc.gov/cancer/cervical/basic_info/screening.htm
5. Colorectal Cancer: What Should I Know About Screening?, CDC, https://www.cdc.gov/cancer/colorectal/basic_info/screening/
6. Who Should Be Screened for Lung Cancer?, CDC, https://www.cdc.gov/cancer/lung/basic_info/screening.htm