Medically reviewed by Sendra Yang on March 18, 2026. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

How Accurate Are At-home Cancer Screening Tests?

At-home screening tests are becoming more popular. Many people choose them because they are easy to use and can be done in the privacy of their own home. Some tests use stool, saliva, or blood. There are now even at-home screening tests that may help find signs of cancer early, but they do not give a cancer diagnosis.

It is important to understand at-home cancer test accuracy and what these tests can do and what they cannot do. Understanding cancer screening accuracy helps people make better choices about their health.

What Are At-Home Cancer Screening Tests?

At-home cancer screening tests are tests where the sample is collected at home and mailed to a lab. The lab then checks the sample for signs that could point to cancer. These tests are used for screening, not diagnosis. Cancer screening tests aim to look for cancer before it starts to cause symptoms, so that it may be easier to treat successfully.[1] An optimal screening test can find cancer early, reduce the chance that someone who is screened regularly will die from cancer, and has more potential benefits than harms.

There are different kinds of at-home cancer screening tests.[1] Some look for signs of colon cancer in stool.[1,2] Some blood tests look for signals that may come from cancer cells.[1] Other tests look at DNA to see if a person was born with a higher chance of getting cancer later in life.

Each type of test works in a different way, and some are better studied than others.

Stool Tests for Colon Cancer

Stool tests for colon cancer are the most trusted at-home cancer screening tests.[1-3] One common test is called the fecal immunochemical test, or FIT. This test looks for small amounts of blood in stool. Blood can be a sign of colon cancer.

FIT is recommended by healthcare providers as a screening option for adults at average risk.[3] It works best when it is done every year. Studies show that FIT can find many cases of colon cancer, but it does not find them all. This is why regular testing is important.[1-4]

Some stool tests also look for tiny pieces of DNA from cancer cells.[3] These tests can find more cancers than FIT alone, but they may also give more false positive results. A false positive means the test suggests a problem when there is none.[4]

When a stool test is positive, a colonoscopy is needed to confirm the result.[3]

Blood Tests That Look for Cancer

Some newer blood tests look for cancer-related signals in the blood.[1] These are often called multi-cancer early detection tests. These tests are still being studied.

Research shows that these blood tests can find some cancers, but they work better for cancers that are already more advanced.[5] They are less reliable at finding cancer very early. Because of this, a normal test result does not mean that cancer is not present.

Health organizations, including the American Cancer Society, say these blood tests should not replace regular cancer screening tests.[5] More studies are needed before they can be used widely.

Genetic Tests for Cancer Risk

Some at-home tests look at DNA to see if a person has a higher chance of developing cancer.[1] These tests do not look for cancer itself. They only look at inherited risk.

These tests can correctly find certain gene changes, but they do not test for all cancer-related genes.[1] A negative result does not mean a person has no cancer risk.[6] A positive result does not mean a person has cancer.

Healthcare providers and genetic counselors can help explain what these results mean and whether more testing is needed.

Why Accuracy Can Be Confusing

No cancer screening test is perfect. Some tests may miss cancer, and some tests suggest cancer when none is present. This is why healthcare providers do not rely on a single test result.

Other health factors matter, such as age, family history, and symptoms.[1] Blood tumor marker tests are not good tools for cancer screening. According to the National Cancer Institute, tumor markers can be high for reasons other than cancer and can be normal even when cancer is present.[6]

Benefits and Risks of At-Home Tests

At-home tests can help people take a proactive part in cancer screening.[1] They are easy to use and less invasive than some medical tests. For some people, they are a helpful first step.

However, these tests also have limitations. False positive results can cause worry and lead to extra testing.[1] False negative results can delay care. At-home tests should not take the place of regular healthcare provider visits or recommended screening tests.

At-Home Lab Testing and Telehealth for Cancer With Everlywell

At-home cancer screening tests can be useful when they are used the right way. With Everlywell, you have the option for an at-home lab test for screening of colon cancer with the FIT Colon Cancer Screening Test. This screens for the presence of hidden blood in stool to assist in detecting early signs of colon cancer. This test is intended for those between the ages of 45 and 75 or those who have an increased risk for colon cancer, such as a family history.

References

1. Screening tests. National Cancer Institute. https://www.cancer.gov/about-cancer/screening/screening-tests. Accessed February 10, 2026.

2. US Preventive Services Task Force. Screening for colorectal cancer: US Preventive Services Task Force recommendation statement. JAMA. 2021;325(19):1965-1977.

3. Screening tests to detect colorectal cancer and polyps. National Cancer Institute. https://www.cancer.gov/types/colorectal/screening-fact-sheet. Accessed February 10, 2026.

4. Davidson KW, Barry MJ, Mangione CM, et al. Screening for colorectal cancer: evidence report and systematic review for the US Preventive Services Task Force. JAMA. 2021;325(19):1978-1998.

5. Multi-cancer detection (MCD) tests. American Cancer Society. https://www.cancer.org/cancer/screening/multi-cancer-early-detection-tests.html. Accessed February 10, 2026.

6. National Cancer Institute. Tumor markers. https://www.cancer.gov/about-cancer/diagnosis-staging/diagnosis/tumor-markers-fact-sheet. Accessed January 2026.