Colorectal cancer is being diagnosed more often in adults younger than 50, making it increasingly important to recognize possible warning signs.
Many symptoms can also be caused by common digestive problems, but doctors say changes that continue or keep returning deserve medical attention. Finding the disease early can greatly improve the chances of successful treatment.
Colorectal cancer starts in the colon or rectum, the lower parts of the digestive system that make up the large intestine. It often begins as a small growth called a polyp, and some polyps can slowly turn into cancer over several years. Screening can find these growths before cancer develops or detect cancer while it is still easier to treat.
For adults at average risk, colorectal cancer screening in the United States generally begins at age 45. However, rising rates among younger adults mean that age alone should not be used to dismiss unusual symptoms. A person in their 20s, 30s or early 40s can still develop the disease.
The American College of Surgeons has developed free educational materials and a symptom checklist to help people prepare for conversations with their primary care doctors. The campaign is based on current medical evidence and clinical experience. Its aim is to encourage people to seek advice sooner when they notice concerning changes.
One possible warning sign is a lasting change in bowel habits. This may include new constipation, diarrhea, unusually narrow stools, or going to the toilet more or less often than usual. A short-lived change is common, but symptoms that continue for several weeks should be discussed with a healthcare professional.
Blood in the stool is another symptom that should not be ignored. The blood may be bright red, appear on toilet paper, or be mixed into the stool, while bleeding higher in the digestive system can sometimes make stools look very dark or black. Hemorrhoids and other conditions can cause bleeding too, but repeated or unexplained bleeding needs proper assessment.
Some people may notice ongoing stomach pain, cramps, bloating, or a feeling that they still need to have a bowel movement after using the toilet. A tumor can sometimes interfere with the normal movement of material through the bowel. Changes in the shape or appearance of stools can also occur.
Colorectal cancer may also cause symptoms that seem unrelated to the bowel. Unexplained weight loss, unusual tiredness, weakness, reduced appetite, nausea, or vomiting can sometimes occur. Slow bleeding from a tumor may also lead to anemia, which can leave a person feeling unusually tired or short of breath.
Risk is not the same for everyone. Having a parent, sibling, or child who has had colorectal cancer can increase a person’s risk, especially when the relative developed cancer at a younger age. People with long-term inflammatory bowel diseases, including Crohn’s disease and ulcerative colitis, may also need earlier or more frequent screening.
Several screening methods are available, including stool tests and colonoscopy. During a colonoscopy, a doctor examines the inside of the colon and rectum with a thin flexible camera. Precancerous polyps can often be removed during the procedure, which means colonoscopy can both detect cancer and help prevent it.
The key message from the American College of Surgeons is that persistent symptoms should not simply be blamed on diet, stress, hemorrhoids, or a sensitive stomach without appropriate medical assessment. Most bowel symptoms will not turn out to be cancer, but it is impossible to know the cause based on symptoms alone. Seeking medical advice early can prevent dangerous delays in diagnosis.
There is no need to panic over every temporary digestive change. However, repeated bleeding, lasting bowel changes, unexplained weight loss, or other unusual symptoms are good reasons to contact a healthcare professional. When colorectal cancer is discovered at an early stage, patients generally have more treatment options and a much better chance of recovery.
For more information about gut health, please see recent studies about the crucial link between diet, gut health, and the immune system and results showing that Low-gluten, high-fiber diets boost gut health and weight loss.
For more information about gut health, please see recent studies about Navigating inflammatory bowel disease (IBD) with diet and results showing that Mycoprotein in diet may reduce risk of bowel cancer and improve gut health.
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