Signs & Symptoms of Colon Cancer

Male patient with colon cancer symptoms

For colon cancer (and any other type of cancer), early detection is important to allow for swift treatment and the best possible outcome and quality of life. Regular screening can prevent colon cancer by detecting precancerous polyps before symptoms develop. When symptoms do develop, it might indicate that the cancer has grown or spread. Colon cancer signs typically vary from patient to patient. Some of these symptoms are caused by the presence of a tumor, while others result from cancerous cells spreading to nearby tissues.

Common signs of colon cancer

The most common signs of colorectal cancer are blood on the surface of the rectum and changes in the frequency or consistency of an individual’s bowel habits. Potential warning signs include:

  • Chronic constipation or diarrhea
  • A persistent urge to pass stool
  • An inability to completely empty the bowels
  • Rectal bleeding
  • The formation of thin, ribbon-like stools

Other colon cancer signs include cramping and bloating in the pelvic or abdominal region, unexpected weight loss and unexplained fatigue. Abdominal pain can occur if a tear develops in the digestive tract, although this is extremely rare.

Notably, colon cancer symptoms will vary from one patient to another. Some of the factors that can affect symptom development include the tumor’s size, location and stage.

What is metastatic colon cancer?

Once colon cancer progresses to its most advanced stage, it becomes known as Stage 4 or metastatic colon cancer. Cancer is said to metastasize when it spreads from the area where it originally developed to another area of the body. Stage 4 colon cancer, for example, commonly metastasizes to the liver, lungs, brain, peritoneum and distant lymph nodes.

When cancer metastasizes, not only does it continue producing symptoms in the area in which it originated, but also in the area that it spread to. So, if colon cancer metastasizes to the liver, for example, the person could begin experiencing liver-specific symptoms such as jaundice, extremity swelling, nausea, midsection bloating or fatigue. Or, if the malignancy metastasizes to the lungs, the person may experience a persistent cough, shortness of breath, difficulty breathing or chest pain.

When does metastatic colon cancer start producing symptoms?

As was noted above, colon cancer is a relatively slow-growing malignancy that generally doesn’t produce noticeable symptoms when it’s still in its early stages. Symptoms often don’t begin to develop until the cancer has reached Stage 4 and metastasized (spread) to another area of the body, at which point symptoms might also become apparent in that distant area.

How long does this process take? In many cases, colon cancer takes years to progress from its initial stages to its most advanced stage. The malignancy will likely continue to not produce any noticeable symptoms for a large portion of that time. Because of this, it’s important to regularly attend colon cancer screenings. Doing so can increase the chances of early detection, which can in turn improve prognoses and quality of life.

How to reduce your risk of colon cancer

Unfortunately, there are certain risk factors for colon cancer that you can’t do anything about (for example, being above age 50 or having a family history of this malignancy). Nonetheless, if you’re concerned about the possibility of developing colon cancer, there are numerous steps you can take to minimize your risk:

  • Eat a nutritious diet. Studies suggest that a high-calorie, high-fat and low-fiber diet—and especially one that regularly includes red meat—could increase the chances of developing colon cancer. So, be sure to incorporate lots of vegetables, fruits and whole grains into your daily meals and snacks.
  • Exercise. Failing to exercise, along with the excess weight that often results from a sedentary lifestyle, can also increase the risk of colon cancer. With that in mind, you should aim to exercise at least 30 minutes on most days of the week. Of course, you’ll want to speak with your physician before starting a new exercise regimen. If you’re not accustomed to much physical activity, your physician may be able to suggest some exercises that will improve your health while also protecting you from injury.
  • Cut down your alcohol consumption. Because drinking excessive amounts of alcohol is a risk factor for colon cancer, you’ll want to limit your intake. Men should generally have no more than two alcoholic beverages each day, while women should have only one.
  • Quit smoking. Smoking increases the risk of developing colon cancer (as well as numerous other health conditions), so it’s important to quit as soon as possible. This extends not only to cigarettes, but also cigars, chewing tobacco and other items containing tobacco.

Young Black male preparing for colon screening


The importance of colon cancer screenings

Colon cancer screening tests can be the difference between receiving a diagnosis of colon cancer and receiving a clean bill of health. Since colon cancer develops from precancerous polyps, removing those polyps before they become cancerous is crucial. A screening test, such as a flexible sigmoidoscopy, stool test or colonoscopy, can find those precancerous polyps so they can be removed. The Centers for Disease Control & Prevention (CDC) recommends adults begin screening for colon cancer at age 45 and then continue being screened at regular intervals after the initial test.

Your physician may recommend screening earlier or more frequently if:

  • You have a history of colorectal polyps or colorectal cancer
  • You have a close relative that has had colorectal cancer
  • You have inflammatory bowel disease (IBD)
  • You have been diagnosed with Lynch syndrome or familial adenomatous polyposis (FAP)

What are colon polyps?

A colon polyp is a growth on the inner surface of the colon that develops due to a change in the colon’s lining. Although colon polyps generally don’t cause symptoms, they can sometimes lead to bloody or black stools.

What if you have colon polyps?

As mentioned above, colon cancer develops from precancerous polyps. With that being said, simply finding colon polyps during an exam is generally not a cause for concern. On the contrary, colon polyps are incredibly common. There are multiple types of colon polyps, and only some of them (adenomatous and serrated polyps) are considered to be precancerous. Others (hyperplastic, inflammatory and hamartomatous polyps) generally do not pose a risk of developing into cancer.

If your examination reveals the presence of colon polyps, a clinician will remove them (either endoscopically or surgically) and then send them to a lab to find out whether they’re cancerous. The results of the lab tests will determine what type of follow-up care you require.

Colon cancer vs. hemorrhoids

If you’ve noticed bloody stools after using the bathroom, along with pain, discomfort, itching, irritation, swelling and lumps around your anus, you might be concerned that you have colon cancer. If so, you’re not alone—many people accidentally confuse the two conditions, mistakenly believing that hemorrhoid symptoms suggest the presence of cancer. However, symptoms like these are generally indicative of hemorrhoids, not colon cancer.

Hemorrhoids are swollen veins that develop inside or outside the anus and rectum. They occur when the blood vessels surrounding the anal canal become congested. Some of the risk factors that can increase the chances of hemorrhoids developing include chronic constipation or diarrhea, pregnancy, lifting heavy objects and a sedentary lifestyle that involves sitting down for extended periods of time.

When to contact a doctor

If you’re experiencing any of these symptoms of colorectal cancer, it’s important to promptly talk with your doctor. Although diarrhea, bloody stools and other complications are often commonly caused by hemorrhoids or other noncancerous conditions, a physician or oncologist can help you determine the most likely reason for your symptoms. If your physician believes your symptoms might be the result of colorectal cancer, you may be advised to schedule a colonoscopy or other type of diagnostic test.

Moffitt Cancer Center offers a complete range of screening tests, diagnostics and treatments in a single, convenient location. If you are experiencing colon cancer signs, we can perform the necessary testing to determine the cause. Comprehensive treatment is also available if a diagnostic test confirms the presence of colon cancer.

To learn more, call 1-888-663-3488 or submit a new patient registration form online. We’ve disrupted the traditional care model to provide patients with rapid care—connecting them with cancer experts in just one day—so that we can start treatment as soon as possible.