Digestive Health

Blood in stool? Keep cool, know these 5-colon cancer signs

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Learn about the connection and how to recognize the symptoms so you can feel better fast.


Is rectal bleeding a sign of colon cancer? Learn about the connection and how to recognize the symptoms so you can feel better fast.


By Suma Magge, MD, Gastroenterology, Nuvance Health


Finding blood in your stool can be an unsettling experience to say the least, especially if you don’t know what caused it. Although rectal bleeding is a symptom of colon cancer, there are many reasons why you may find blood in your stool. Identify the five common signs of colon cancer so you can better understand what your body is telling you.


Learn about your colorectal cancer risk. Take a Colon Cancer Risk Quiz now.


Why is there blood in my stool?


Blood in the stool can be caused by many conditions, ranging from mild to serious. Here are some common reasons why you might have blood in the stool.

  • Hemorrhoids: Swollen blood vessels in the rectum or anus can cause bleeding. Hemorrhoids are a common cause of blood in the stool.
  • Anal fissures: Small tears in the lining of the anus can cause bleeding, especially during bowel movements.
  • Diverticular disease: Small, bulging pouches can develop in the digestive tract, usually in the colon. When these pouches become inflamed or infected, they can cause bleeding.
  • Inflammatory bowel disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause inflammation and ulcers in the digestive tract, leading to bleeding.
  • Colon polyps or cancer: Abnormal growths in the colon (polyps) or cancer can cause bleeding, which may be visible in the stool.
  • Peptic ulcers: Sores that develop on the lining of the stomach, esophagus, or small intestine can cause bleeding, which may appear in the stool.
  • Esophageal varices: Swollen veins in the lower esophagus can rupture and bleed, leading to blood in the stool. This is often associated with liver disease.
  • Infectious diarrhea: Certain infections, such as those caused by bacteria, viruses, or parasites, can lead to bloody diarrhea.


It's important that you speak with your doctor if you have blood in your stool to determine the underlying cause and appropriate treatment.


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Understanding colon cancer


Since colon cancer is one of the more serious causes of blood in the stool, it is important to understand what it is. Colon cancer, also called colorectal cancer, is a type of cancer that affects the colon or rectum. It usually starts as a small growth called a polyp, which can turn into cancer if not treated.


In the United States, colon cancer is one of the most common types of cancer. According to the American Cancer Society, it's estimated that about 1 in 23 men and 1 in 25 women will get colon or rectal cancer during their lifetime.


Learn more about colorectal cancer at the Nuvance Health Cancer Institute.


While colon cancer can happen at any age, it's more common in people over the age of 45. However, new research shows that more younger people are being diagnosed with colorectal cancer therefore the age for screenings has been recommended for age 45 instead of age 50. According to American Gastroenterological Association, colorectal cancer will be the leading cause of cancer-related death among 20 to 49-year-olds by 2030. Putting off screening until age 50 is a grave mistake. Factors that might increase the risk of colon cancer include a family history of the disease, personal history of polyps or inflammatory bowel disease, not being active, having a diet high in red or processed meats and smoking.


Related Content: What will happen if my colonoscopy is abnormal?


Rectal bleeding is a usual sign of colon cancer because the cancerous tumors can bleed into your digestive tract, which causes a discharge of blood from your rectum or in your stool. However, it's important to know that not all cases of rectal bleeding mean colon cancer. Other reasons like hemorrhoids or anal fissures can also cause it. If you have rectal bleeding, it's crucial to see your doctor for a proper diagnosis.


Recognizing colon cancer symptoms


Recognizing the symptoms of colon cancer is crucial for early detection. Here are five of the most common signs:

  • Rectal bleeding. While this can be a sign, it doesn't always mean colon cancer is present. Other issues like hemorrhoids can cause rectal bleeding. Bright, red-colored blood in your stool is called hematochezia. If you have persistent or unexplained bleeding from your rectum or notice bright, red-colored blood in your stool, see your doctor. 
  • Changes in bowel habits. Sudden changes in your bowel movements such as constant diarrhea or constipation could signal colon cancer. If your symptoms last more than a few days, speak with your doctor. 
  • Abdominal pain or cramps. Persistent pain with bloating may indicate colon cancer. Get it checked out by your doctor. 
  • Unexplained weight loss. Losing weight without a clear reason might be a sign of colon cancer, especially in later stages.
  • Fatigue and weakness. Fatigue and weakness are common and symptoms of many different conditions. If you have any of the above symptoms and you're constantly tired despite rest consult your doctor. The feeling could be a result of anemia due to blood loss from colon cancer that is bleeding inside your bowel.


Related Content: Is someone being a pain in the butt about colonoscopy screenings? Here is what to say to them.


Remember that all five symptoms might be caused by other conditions too. Consulting your doctor is important for accurate diagnosis and treatment.


Book Now with a Colorectal Cancer Specialist


Diagnosing and treating colon cancer


Early detection is crucial for better outcomes in colon cancer. Here's how it's diagnosed and treated:

  • Diagnosis. If you experience symptoms like rectal bleeding, see your doctor. Your doctor may complete a physical exam and recommend further tests such as a colonoscopy. A colonoscopy is a common procedure to check for cancerous growths in the colon. Biopsy samples taken at the time of the colonoscopy can confirm cancer once tested at a lab. 
  • Treatment. The treatment depends on factors like cancer stage and overall health. Surgery is often the first option to remove the tumor. Chemotherapy and radiation therapy may follow, especially for advanced stages. Minimally invasive surgeries such as laparoscopy are also used. 
  • Screening. Regular colonoscopy screenings are vital for early detection. Getting a colonoscopy beginning at age 45 is recommended for most people, or earlier if there's a family history of colorectal cancer. 


If you notice symptoms or have concerns, consult your doctor for proper diagnosis and treatment options.


The bottom line: While rectal bleeding can be alarming and may be a symptom of colon cancer, it's essential that you recognize several other factors that could cause bleeding. Understanding all of the signs of colon cancer can help you decide if you need treatment. Remember to consult your doctor if you notice blood in your stool that doesn’t appear to go away after bowel movements. Your doctor can help make an accurate diagnosis and provide the appropriate treatment options for you. Regular colonoscopy screening are also crucial for early detection of colon cancer and they save lives. If you see blood in your stool, keep cool, and remember the five symptoms of colon cancer. 


Learn about your colorectal cancer risk. Take a Colon Cancer Risk Quiz now.