Colon cancer often presents with changes in bowel habits and rectal bleeding, but some people have no symptoms early on. If you notice any of the following symptoms that persist for more than a few weeks, it’s important to see a healthcare professional promptly. Direct answer
- Common symptoms: changes in bowel habits (diarrhea, constipation, or narrowing of the stool), a feeling that the bowel doesn’t empty completely, bright red or dark blood in or on the stool, abdominal cramping or pain, and fatigue or weakness from anemia.
- Less common symptoms: unintended weight loss, a lump in the abdomen or rectum, nausea or vomiting, and a feeling of fullness or bloating.
- Symptoms suggesting spread or advanced disease: persistent abdominal pain, jaundice (yellowing of the skin or eyes), swelling of the abdomen, shortness of breath, or a new, unexplained lump in the abdomen.
What to do
- If you have any of the above symptoms that persist for more than a few weeks, or you have a family history or risk factors (age, inflammatory bowel disease, certain genetic conditions, lifestyle factors), consult a clinician for evaluation.
- Screening is important even without symptoms. Regular colorectal cancer screening begins at age 45–50 for average risk, but may start earlier for those with higher risk; discuss your personal plan with a healthcare provider.
- If there is sudden, severe abdominal pain, vomiting, or symptoms of a bowel obstruction, seek urgent medical care.
Notes
- Some symptoms overlap with other non-cancer conditions (such as hemorrhoids or infections), so a professional evaluation is essential to determine the cause.
- Screening tests (like colonoscopy, stool tests, or imaging) can detect cancer or pre-cancerous changes before symptoms develop.
If you’d like, share your age, risk factors, and whether you’re experiencing any specific symptoms, and a tailored overview of what to discuss with a clinician can be provided.
