Symptoms, Stages, Outlook, and More

Colon cancer can be caused by cancer in the large intestine or rectum. Your colon and your rectum make up the lower part of your digestive system.

According to the Centers for Disease Control and Prevention (CDC), colon cancer — also known as colorectal cancer — is the third most common type of cancer in the United States when certain common skin cancers are excluded. According to the American Cancer Society (ACS), colorectal cancer will affect 1 in 23 men and 1 out 25 women.

The symptoms, treatment, and outlook for colon cancer will generally depend on the stage your cancer is in when you’re first diagnosed.

Learn more about colon cancer stages, causes, and risk factors — plus resources to help you find support.

Doctors use staging to determine how advanced the cancer is. It’s important for a doctor to know the stage of the cancer because it helps determine the best treatment plan for you. It’s also a good way to estimate your long-term outlook.

Stage 0 colon carcinoma is the earliest stage. Stage 4 is the advanced stage. Here’s how the stages are defined:

  • Stage 0.This stage, also known as carcinoma-in-situ, is where abnormal cells are located in the inner lining or rectum of the colon.
  • 1. StageThe cancer has spread to the lining (or mucosa) of the colon or the rectum. It may have even reached the muscle layer. It hasn’t spread to nearby lymph nodes or to other parts of the body.
  • Stage 2. The cancer has spread to the walls of the colon or rectum, or through the walls to nearby tissues, but hasn’t affected the lymph nodes.
  • Stage 3.The cancer has spread to the lymph nodes and not to other parts.
  • Stage 4.The cancer has spread beyond the liver to other organs like the lungs or liver.

It is possible to not experience any symptoms of colon cancer, particularly in the early stages. If you do experience symptoms in stages 0 through 2, they’ll often include:

You may also have other, less serious conditions that can cause many of these symptoms. However, it’s a good idea to see a doctor if you’ve had any of these symptoms for longer than a week or two. Your doctor and you can discuss your symptoms and decide if a colon cancer screening is necessary.

Stage 3 and 4 symptoms (late-stage symptoms).

Stages 3 and 4 are when symptoms of colon cancer are more apparent. These symptoms are not the only ones you may experience.

If colon cancer spreads from one part of your body to another, you might also experience:

Symptoms according to stage

You might be surprised to know that there are many types of colon cancer. There are many types of colon cancer cells. Colon cancer can also be caused by cells in different parts or the digestive tract.

Adenocarcinomas are the most common form of colon cancer. Adenocarcinomas are found in cells that make mucus, either in the colon and rectum. Adenocarcinomas account for the majority of colon cancer cases, according to the ACS.

Other types of cancer are more common in colon cancers.

  • lymphomas, These can form in the lymph nodes or in your colon first
  • carcinoids, which are found in hormone-making cells in your intestines
  • Sarcomas, which are found in soft tissues like the muscles in your colon
  • gastrointestinal stromal tumors,They can be benign at first, but then turn cancerous.

Researchers continue to study the causes of colon carcinoma.

Genetic mutations, which can be inherited and acquired, may cause cancer. These mutations don’t guarantee you’ll develop colon cancer, but they do increase your chances.

Polyps can be formed when abnormal cells accumulate in the colon lining. These benign growths are usually small. Untreated polyps may become cancerous if they are not treated. These growths can be removed by surgery.

There are several risk factors that can increase your likelihood of developing colon carcinoma. Having one of these risk factors doesn’t automatically mean you’ll get colon cancer, but it does make it more likely than if you had no risk factors.

Risk factors you can’t change

Some factors that increase your risk of developing colon cancer can’t be changed. Colon cancer risk factors include your age, ethnicity and family history.

Risk factors you can’t control include:

  • being over 50
  • A history of colon polyps
  • A history of bowel disease
  • A family history colorectal cancer
  • Certain genetic syndromes, like familial adenomatous poposis (FAP), can be caused by certain genes
  • Being of Ashkenazi or African Jewish descent

You can reduce risk factors

You can avoid other risk factors. This means that you can change these risk factors to lower your chances of developing colon carcinoma. These are some of the risk factors that you can avoid.

Early detection of colon cancer is the best way to cure it. Colon cancer is often not diagnosed until its early stages. Routine screenings are a good way to catch it early.

In light of the increasing incidence of colon cancer in younger people, the US Preventive Service Task Force and ACS recommend that colon cancer screening be started at 45.

The American College of Gastroenterology recommends screening for colon cancer at 40 years of age.

Your doctor will begin by asking about your medical history and family history. They’ll also perform a physical exam. They may also press on your abdomen to detect lumps or polyps.

Fecal testing

The ACS recommends yearly fecal tests. Hidden blood in your stool can be detected by fecal tests. There are two types of fecal tests: the guaiac based fecal blood test (gFOBT), and the fecal immune chemical test (FIT).

Guaiac-based Fecal occult Blood Test (gFOBT).

Guaiac can be described as a plant-based substance that is used to coat a special card where your stool sample has been placed. The card will turn a different color if blood is found in your stool.

You’ll have to avoid certain foods and medications, such as red meat and nonsteroidal anti-inflammatory drugs (NSAIDs), before this test. They could affect your test results.

Fecal immunochemical test

The FIT detects hemoglobin (a protein found in blood). It’s considered more precise than the guaiac-based test.

That’s because the FIT is unlikely to detect bleeding from the upper gastrointestinal tract (a type of bleeding that is rarely caused by colorectal cancer). Additionally, the results of this test aren’t affected by foods and medications.

At-home testing

Multiple stool samples are required for these tests. Your doctor will likely give you test kits to use at your home.

Companies such as Everlywell and LetsGetChecked offer at-home testing kits.

These kits may require you to send a sample of your stool to a laboratory for evaluation. Your test results should be available online within five business days. Afterward, you’ll have the option to consult with a medical care team about your test results.

The Second Generation FIT can also be purchased online, but the stool sample doesn’t have to be sent to a lab. The test results are available in less than 5 minutes. The test is FDA-approved and accurate. It can also detect other conditions, such as colitis. However, there’s no medical care team to consult with if you have questions about your results.

Blood tests

Your doctor may run blood tests to get a better idea of what’s causing your symptoms. Other diseases and conditions can be ruled out by liver function tests and complete blood count.


The sigmoidoscopy procedure is minimally invasive and allows your doctor to examine the last section of your colon, your sigmoid, for abnormalities. Flexible sigmoidoscopy is also known as flexible sigmoidoscopy. It involves a flexible tube that has a light attached to it.

The USPSTF recommends a flexible sigmoidoscopy once every five years or once every 10 years with a yearly FIT.

The ACS recommends that you have a flexible sigmoidoscopy every five years.


A colonoscopy involves using a long tube that has a small camera attached. This allows your doctor access to your colon and rectum to examine for any abnormalities. It’s usually performed after less invasive screening tests indicate that you might have colon cancer.

Your doctor may also be able to remove abnormal tissue during a colonoscopy. These tissue samples can then go to a laboratory to be analysed.

Of all the diagnostic methods available, colonoscopies or sigmoidoscopies are the most effective in detecting benign growths that could develop into colon cancer.

The ACS and the USPSTF recommend a colonoscopy once every 10 years.


Your doctor might order an X-ray with a radioactive contrast solution, which contains the chemical element Barium.

Through a barium catheter, your doctor will insert this liquid into the bowels. Once the liquid is in place, the barium solution covers the colon’s lining. This enhances the quality and clarity of X-ray images.

CT scan

A CT scan gives your doctor a detailed image and description of your colon. A CT scan that’s used to diagnose colon cancer is sometimes called a virtual colonoscopy.

There are many factors that go into the treatment of colon cancer. Based on your overall health, stage and type of colon cancer, your doctor will recommend the best treatment plan.


In the earliest stages of colon cancer, it’s often possible for your surgeon to remove cancerous polyps through surgery. If the polyp hasn’t attached to the wall of the bowels, you’ll likely have an excellent outlook.

If you have cancer spread to your bowel walls and has spread to the rectum or colon, your surgeon might need to remove some of the lymph nodes. The surgeon may be able to reconnect the healthy colon to the rectum. If this isn’t possible, they may perform a colostomy. This involves making an opening in the abdominal wall to allow waste to be ejected. A colostomy can be temporary or permanent.


Chemotherapy is the use of drugs to kill cancer cells. People with colon cancer often have chemotherapy after their surgery. It is used to eliminate any remaining cancerous cells. The growth of tumors is also controlled by chemotherapy.

The following chemotherapy drugs are used to treat colon carcinoma:

  • capecitabine (Xeloda).
  • fluorouracil
  • Eloxatin (oxaliplatin)
  • Irinotecan (Camptosar).

Side effects from chemotherapy can often be severe and require additional medication.


Radiation uses a powerful beam to destroy cancerous cells, much like X-rays. Radiation therapy is often used in conjunction with chemotherapy.

Other medications

Targeted therapies, immunotherapies and targeted therapies may also be recommended. The FDA has approved the following drugs to treat colon carcinoma:

  • bevacizumab (Avastin)
  • ramucirumab (Cyramza).
  • ziv-aflibercept (Zaltrap)
  • cetuximab (Erbitux)
  • panitumumab (Vectibix)
  • regorafenib (Stivarga)
  • pembrolizumab (Keytruda)
  • nivolumab (Opdivo)
  • ipilimumab (Yervoy)

They can treat metastatic, or late-stage, colon cancer that doesn’t respond to other types of treatment and has spread to other parts of the body.

A diagnosis of colon cancer can be distressing and alarming. Colon cancer is treatable if caught early. In fact, according to the ACS, colon cancer that’s diagnosed before it has spread past the colon and rectum has a 91 percent 5-year survival rate. These survival rates were calculated using data from 2010 through 2016. In recent years, new cancer treatments have led a rise in survival rates.

In recent years, however colon cancer cases have increased in younger people. According to the ACS report, colon cancer deaths have declined in older adults but increased in younger people between 2008 and 2017.

Certain risk factors for colon cancer, such as family history and age, aren’t preventable.

Lifestyle factors that can lead to colon cancer can be avoided. Changing them could help reduce your risk.

You can take steps to reduce your risk now by:

Another preventive measure is: Get a colonoscopy and other cancer screenings when you turn 45. The better the outcome is if cancer is detected early.

The first step in treating colon carcinoma is surgery. The outcome of your surgery will determine the next steps.

No matter what happens on your treatment journey, you’ll need support along the way. It’s important to talk to your medical team and loved ones and to feel comfortable reaching out for help. To build a support network, check out these resources.

  • The Colorectal Cancer Alliance Helpline The free service (877-422-2030), can connect you with resources and peer support.
  • Live chat for the Colorectal Cancer Support Group Meets every Wednesday between 12 noon and 1pm EST
  • Blue Hope NationSupportive Facebook group for patients and their families with colon cancer.
  • Cancer Care offers a range of services. Colorectal Cancer Patient Support GroupAn oncology social worker will guide you.
  • Fight Colorectal CancerOffers a resource library to people with colon cancer, including podcasts and videos. This will help you through treatment and beyond.

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