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Early Symptoms of Colorectal Cancer, By a Doctor

CRC can be often cured if found early.
FACT CHECKED BY Emilia Paluszek

Every year, colorectal cancer (CRC) kills over 50,000 people in the United States. It is the second leading cause of death from cancer. CRC can often be cured if it is found early. Very importantly, a screening test can find CRC at an early stage. There are often no symptoms in the early stages of CRC, but when they appear, they may include the following signs. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Blood in the Stool or Rectal Bleeding


hand of a woman closing the lid of a toilet

Blood in the stool or rectal bleeding occurs because the cancer has eroded the blood vessels in the lining of the colon or rectum. This bleeding is usually not painful. Hemorrhoids can also cause bleeding although blood usually coats the stools rather than is mixed through it. In any event, see a doctor for blood in or on your stool


Change in Stool Caliber

Restroom sign on a toilet door,on wood background

A change in stool caliber, such as narrower stools, can be a sign of CRC. This symptom is caused by a tumor that partially blocks the colon or rectum causing stool to squeeze through a narrowed tube like toothpaste coming out. Irritable bowel syndrome can also cause pencil-thin stools. If narrowed stools persist for more than 3 days see a doctor


Diarrhea or Constipation

upset woman in toilet by diarrhea, constipation, hemorrhoids, piles

Diarrhea and constipation may alternate and are caused by a tumor that obstructs the normal passage of stool through the colon or rectum.


Cramping or Abdominal Pain

mature woman experiencing stomach pain from fatty liver disease

Cramping or abdominal pain may be caused by gas and bloating from obstruction of the bowel by a CRC tumor.


Bloating or Feeling that Your Bowel Does Not Empty Completely

Young woman suffers, writhes in abdominal pain lying on couch in living room at home interior

A feeling of bloating or incomplete evacuation after a bowel movement may be caused by a CRC tumor.


Weakness And Fatigue

Weakness and fatigue are common symptoms of cancer, but can also be caused by other conditions.

These symptoms can also be caused by benign (non-cancerous) conditions such as hemorrhoids or irritable bowel syndrome (IBS). If you have any of these symptoms, it does not mean you have CRC. However, if you have any of these symptoms and they last for more than a few weeks, see your doctor so the cause can be found and treated, if needed. And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Gethin Williams MD Ph.D. is the Medical Director of Imaging & Interventional Specialists.

Gethin Williams, MD, Ph.D
Gethin Williams, MD, Ph.D. is the Medical Director of Imaging & Interventional Specialists. Read more about Gethin
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