Cancer screening involves testing otherwise healthy people to look for evidence of the disease when they do not have symptoms (asymptomatic). There are screening tests for various types of cancer, including cervical cancer, breast cancer, and colorectal cancer.
Cancer screenings have an extremely important role in cancer prevention, and they increase the chance of early detection when treatment is more likely to be successful. It must be noted that screening tests do not normally diagnose cancer but instead pick up on abnormal findings that require further investigation.
Read on to learn more about cancer screenings, their benefits and risks, and whether you should participate in these tests.
There are many cancer screening tests, each with risks, benefits, and varying accuracy. For a screening test to be recommended, it must be safe, accurate, and useful.
Cancer screenings are studied extensively before official recommendations are made. Tests proven to improve outcomes or reduce cancer rates are now recommended as part of cancer screening guidelines (we’ll discuss this later in this article).
Listed below are some methods and tests used in screening practices.
Physical Examination: A general body exam is useful to check for any sign of disease — for example, when you find a physical lump under your skin. Skin checks are useful for detecting skin cancer. A history of the patient’s previous health conditions, lifestyle habits, and family history will also be taken during the examination.
Imaging: Imaging techniques gain internal pictures of the body. These screening tests include MRI (magnetic resonance imaging) for different types of cancer, mammograms that provide X-ray images of the breasts to screen for breast cancer, and computed tomography (CT) scans, which are used to screen for lung cancer.
Stool Tests: These are used to look for abnormal DNA or blood that can be used to screen for colorectal cancer or colon cancer.
Blood Tests: These can be used to look for tumor markers such as PSA, which can be used as part of prostate cancer screening and monitoring.
Colonoscopy: With this test, a camera goes into the rectum to screen for colorectal cancer and look for precancerous polyps.
Pap Test (Pap Smear): This test involves taking a sample of cells from the cervix as a screening test for cervical cancer. These cells can also be tested for HPV (human papillomavirus), a virus that has been shown to cause the disease.
Genetic Testing: This testing can be performed in patients with a positive family history of cancer to look for certain mutations that put individuals at an increased risk of the disease. Depending on their risk, these patients may need to partake in earlier and more regular screenings and follow-ups.
It must be noted that no single test is perfect for picking up cancer. Your healthcare provider will be able to provide information on the risks and benefits of each. Some tests are quick, easy, and minimally invasive. However, others, such as a colonoscopy, carry risks and can be uncomfortable. Talk to your doctor about which tests are suitable for you.
Cancer screenings can help detect and treat changes before they turn into cancer, thereby playing a role in cancer prevention. For instance, a Pap smear can detect abnormal cells that can be treated before they develop into cancer.
Cancer screening also leads to early detection of cancer. When cancer is caught in its early stage, it’s easier to treat or cure. By the time a patient has symptoms, the cancer might have grown or spread, making it more difficult to treat and even possibly incurable. Cancer screening has subsequently been shown to reduce cancer deaths through early detection.
A study published in The Lancet Oncology found a 25% reduction in breast cancer deaths in the first 10 years associated with mammography screening between the age of 40-49 years.
There is ongoing research and clinical trials to improve our understanding of cancer's causes and risk factors to identify which screenings may be beneficial.
It must be noted that, as with most tests and investigations, screening tests carry risks and are not always useful. The risk may be associated with the test itself or how the result is interpreted.
The risks associated with cancer screening can come from performing the test itself. The more invasive the test, the more significant the risks. For example, a colonoscopy carries a small but serious risk of the scope (camera) causing a tear to the lining of the bowel. Your healthcare provider will discuss each screening and its risks and benefits beforehand so you can decide whether to proceed.
A false positive result gives an abnormal result when no cancer is present. This can lead to significant anxiety and further tests and investigations, which can also carry risks.
On the other hand, screening tests can give false negative results. This means the result comes back normal even though there is cancer, giving false reassurance. This may cause a delay in receiving diagnosis and cancer treatment. If a screening test is negative but you have or develop symptoms, it’s urgent to speak to your doctor.
Finally, a screening test may lead to a cancer diagnosis that would likely not have caused problems or a threat to life. A diagnosis of cancer can significantly affect a person’s mental health and well-being, not to mention the physical effects of treatment itself. Sometimes treating cancer does not make a person healthier or live longer.
Certain screening tests are only recommended for people who are at higher risk for that type of cancer. Others are recommended based on age alone. Recommendations result from extensive research and clinical trials where researchers have discovered which members of the population will receive the most benefit and the least harm from the screening test.
You may want to speak to your doctor about cancer screenings if:
If you want to understand your cancer risk further, use the Ezra cancer risk assessment calculator.
The United States Preventive Services Task Force (USPSTF) make recommendations for doctors on how they can help patients avoid diseases or detect them early. The organization is made up of experts and doctors — recommendations are based on research about how to prevent disease.
The screening tests described below have been extensively studied and are now considered standard tests.
Breast cancer screenings don’t prevent cancer, but they increase the chance of early detection when it’s easier to treat. Per the USPSTF, a mammogram every other year is recommended for all women starting at age 40.
Learn more about breast cancer risk factors and consult your healthcare provider to discuss screening. Alternatively, you could also consider booking an Ezra Mammogram in three easy steps.
The USPSTF recommends colorectal cancer screening for all adults aged 45-75 years. Those older than 75 should speak to their doctor as screening is advised on an individual basis. If you possess risk factors, you should contact your healthcare provider as you may need to start screening earlier. They will discuss which tests are best for you.
Learn more about the signs and symptoms of colorectal cancer and if you are at risk.
The USPSTF and the American Cancer Society recommend cervical cancer screening for women. The American Cancer Society has recently updated its guidelines and recommends that women aged 25 commence screening with a primary HPV test every five years up to the age of 65 years.
Untreated human papillomavirus causes 95% of cervical cancer, according to the World Health Organization. Pap smears are also used as a method of screening and can be used in combination with HPV testing. If you’re eligible for cervical screening, talk to your healthcare provider.
Screening is available for other types of cancer. However, they are not recommended as standard tests. Instead, they are based on the presence of risk factors or on an individual basis.
For example, lung cancer screening is recommended for patients aged 50-80 years with a 20-pack-year smoking history. This means those who have smoked 20 cigarettes a day for 20 years. Find out more about lung cancer screening and guidelines.
Prostate cancer screening has been extensively studied. As the second most common cancer in men worldwide, there’s certainly a need. However, the National Cancer Institute finds that screening tests, such as the PSA test, have limited accuracy and screening has not been shown to reduce cancer deaths or improve outcomes.
On the other hand, a recent study has shown that a prostate MRI could reduce prostate cancer mortality and unnecessary treatment. Learn more about prostate MRI and its role in screening.
Screening tests are vital for cancer prevention, early detection, and reducing cancer deaths.
It’s important to understand your risks and talk to your healthcare provider about what’s available and right for you.
Another way to screen for potential cancer and many other health conditions is to get an Ezra Full Body MRI scan. It takes just one hour and gives information on up to 13 different organs to identify potential abnormalities that can be treated before they become problematic.
Take a proactive approach to your health before symptoms even arise. Consider booking a scan today.
