Colorectal cancer: warning signs and why screening saves lives
Colorectal cancer is one of the most common cancers worldwide — yet, unlike many others, it is largely preventable and, caught early, highly curable. The key is twofold: recognising the signs that should not be ignored, and getting screened before any symptom appears.
Why early detection matters
Most colorectal cancers develop slowly, from a polyp — a small, benign growth of the intestinal lining — that can, over years, turn malignant. That slow evolution is actually an opportunity: if the polyp is found and removed in time, the cancer can be prevented altogether.
When the disease is found at an early stage, treatment is simpler, less aggressive, and cure rates frequently exceed 90%. Found late, it becomes far harder to treat. Waiting for symptoms to "pass on their own" is the most costly choice of all.
Signs you should not ignore
Many of these symptoms have harmless causes too, but none should be dismissed if they persist. See a doctor if you notice:
- Blood in the stool — bright red or dark, or black, tarry stools.
- A change in bowel habits lasting more than a few weeks — diarrhoea, constipation, or alternating between them, appearing for no clear reason.
- Persistently thin, "pencil-like" stools.
- A feeling of incomplete emptying after a bowel movement.
- Persistent abdominal pain or cramping, or bloating that won't settle.
- Unexplained fatigue or anaemia (iron deficiency) — sometimes the only sign of small but continuous bleeding.
- Unexplained weight loss.
Screening: the check done before symptoms
The most important message is this: screening is done while you feel perfectly healthy. Its purpose is to catch polyps and early changes before they cause any sign.
At what age
For people at average risk, screening begins around ages 45–50. If you have risk factors — first-degree relatives with colorectal cancer or polyps, a personal history of polyps, inflammatory bowel disease (ulcerative colitis, Crohn's), or certain hereditary syndromes — screening may start earlier and be repeated more often. Talk to your doctor about the right timing for you.
What methods exist
- Colonoscopy — the gold standard. It allows both a complete examination of the colon and removal of polyps during the same procedure. If the result is normal, it is usually repeated at about 10 years.
- Faecal immunochemical test (FIT) — a simple stool test that detects blood invisible to the eye. Done yearly; if positive, a colonoscopy follows.
What a colonoscopy is actually like
Fear of colonoscopy leads many people to postpone it for years — often needlessly. In reality, the procedure usually takes 20–30 minutes and is done under sedation, so you feel no discomfort. The least pleasant part is the preparation the day before (a solution that empties the bowel), not the procedure itself.
If a polyp is found during the examination, it is most often removed on the spot, painlessly. In effect, the same procedure that diagnoses can also prevent cancer.
If the diagnosis is cancer
A diagnosis of colorectal cancer no longer means today what it meant a few decades ago. Modern treatment is multidisciplinary and individualised, and surgery has become far gentler: minimally invasive — laparoscopic and robotic operations allow small incisions, less bleeding, less postoperative pain and faster recovery within ERAS (enhanced recovery after surgery) protocols. The goal remains twofold: complete, oncologically sound removal of the tumour — and preserving quality of life wherever possible.
The bottom line
Colorectal cancer can be prevented and, caught early, cured. Don't ignore persistent signs and don't postpone screening — especially if you are over 45 or have a family history. A timely colonoscopy can, quite literally, be the decision that saves your life.
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