Can You Still Have Colon Cancer Even If There Is No Visible Blood in Your Stool and the Fecal Occult Test Came Back Negative?

Understanding Colon Cancer Symptoms and Testing

If a stool test is negative, it does not always mean colorectal cancer or colon polyps are not present. That is because these tests can miss polyps and some cancers. If you have risk factors for colorectal cancer, your doctor may recommend various intervals between tests. The three main symptoms of bowel cancer are blood in the stools, changes in bowel habit, and abdominal pain. However, these symptoms are very common and most people with them do not have bowel cancer.

Differentiating Colon Cancer Symptoms

Can you have colon cancer without having visible blood in your stool? Yes. Many colon cancer patients have no visible blood in the stool, and many also have no or very few symptoms of colon cancer, even when it is fairly advanced. That’s because colon cancer isn’t one disease. Symptoms and prognoses vary depending on where the cancer is located. Left-sided and right-sided cancers of the colon are different. Most publicity is given to left-sided cancers and their symptoms. Right-sided colon cancer can be harder to detect and is often diagnosed because of anemia instead of visible blood in the stool.

Right-Sided Colon Cancer Symptoms

Right-sided colon cancer can be a silent killer because it either doesn’t present symptoms, presents very vague symptoms, or the symptoms are easily explained as something else. I had serious anemia, which was the first clue something was wrong. I was later diagnosed with no other symptoms, but a T3 tumor of the right hepatic flexure. However, because the anemia came on slowly, my body had adapted, and it wasn’t until the anemia was life-threatening that my body couldn’t cope any more. Looking back, I can now see that I had less energy and felt unwell, but it is easy to explain this away as a busy lifestyle or symptoms of aging. If you feel under the weather for more than a couple of weeks, you should see your doctor and get some blood tests.

Does Blood in the Stool Mean I Have Cancer?

No. It is possible the cause is something completely benign and is not cancer. However, it is very important to get yourself checked by a doctor to rule out more malignant causes. But don’t panic, as it could be something very simple such as hemorrhoids or an ulcer or something serious but not cancerous such as inflammatory bowel disease. Only 2–10% of cases are caused by cancer.

Understanding Fecal Occult Tests

Does a negative fecal occult test or FIT mean I don’t have cancer? No. A fecal occult blood test (FOBT) simply examines your stool for signs of non-visible blood. Although we tend to say FOBT, this is an older test and is often now replaced by FIT (faecal immunochemical test). Both are low-cost screening tests that are very useful for highlighting people who need further investigation in large groups or populations. However, they are not intended to be diagnostic tests for colon cancer.

Further Investigation Needed

The presence of blood in your stool does not necessarily mean you have cancer, but the absence of blood doesn’t mean you’re cancer-free. Some tumors bleed intermittently or not at all, and bleeding can be missed. You should have had a blood test for anemia and for cancer markers in your blood, as all these tests are important to help your doctor figure out what’s happening. Having anemia doesn’t mean you have cancer, but anemia is a common result of colon cancer. You can have cancer and have no markers in your blood, which just means the cancer hasn’t yet spread.

Other Clues and Tests

If you are middle-aged or older and have symptoms or are worried, you should really consider having a colonoscopy. A colonoscopy can rule out or diagnose tumors. Even though it might possibly miss very small polyps, especially those on the right hand side, it is not going to miss a tumor. A tumor might also be indicated by a less invasive intervention such as a CT scan, but even then, it will need confirmation with a colonoscopy.

Colon Cancer Risk Factors

Do not be complacent that because you exercise, eat well, don't smoke, and drink very little, and are still relatively young, you are immune to colon cancer. I know lots of people who do not have the common risk factors and have still developed colon cancer. Try to do what you can to lower your risk but understand that a lower risk doesn’t mean no risk. You don’t ‘prevent’ colon cancer by eating well and exercising; you simply reduce your risk. Conversely, you don’t get colon cancer because you once ate AB or C. The best thing you can do is to take care of the biome in your gut and ensure you have plenty of 'good' bacteria. Remember, poor diet leads to a poorer biome. If you have to have antibiotics, take care to recolonize your gut with good bacteria by taking probiotics after your course of antibiotics is finished.

Colon cancer is one of the most treatable cancers when caught early but one of the most deadly when caught late. Your GI tract is as important to your health as many other bodily structures that get more attention, like the heart. Be aware of what can go wrong and prioritize keeping it healthy. Even if the worst happens and it turns out you have colon cancer, there are many people who have been successfully treated and cured and go on to live healthy and long lives after treatment. Ignoring it, however, isn’t going to make it go away. Only surgery, possibly with adjunct chemotherapy, is going to cure you.