22/02/2026
🩺 Early Signs of Colon Cancer
Colore**al cancer often develops slowly and may be asymptomatic in early stages
which is why screening is crucial.
However, some early warning signs may appear.
🚩 1. Change in Bowel Habits
Persistent diarrhea or constipation
Alternating diarrhea and constipation
Change in stool caliber (narrow or “pencil-thin” stools)
Feeling of incomplete evacuation (tenesmus)
🩸 2. Re**al Bleeding or Blood in Stool
Bright red blood
(distal lesions)
Dark or mixed blood within stool
Occult blood detected on screening tests
⚠️ Any unexplained re**al bleeding should be evaluated.
🩺 3. Iron Deficiency Anemia (Especially in Older Adults)
Fatigue
Pallor
Dyspnea on exertion
Often due to chronic occult bleeding
Particularly suggestive of right-sided colon tumors
⚖️ 4. Unexplained Weight Loss
Without diet or lifestyle change
😣 5. Persistent Abdominal Discomfort
Cramping
Bloating
Gas pain
Intermittent colicky pain
🚨 6. Features of Partial Obstruction
(Later but Sometimes First Presentation)
Progressive constipation
Abdominal distension
Vomiting (advanced cases)
🎯 Important Clinical Pearl
Early colon cancer may present only with anemia or subtle bowel habit change — especially in patients over 45–50 years.
Screening (colonoscopy or stool-based testing) is recommended even in asymptomatic individuals starting at age 45 in average-risk populations.