Colorectal cancer (also known as colon cancer) may not cause any symptoms in its early stages. Symptoms typically appear after the disease has spread.
Signs and symptoms of colorectal cancer
Colorectal cancer symptoms vary according to the location of the tumour.
Changes in bowel movements, including persistent diarrhoea or constipation
Feeling that you can’t empty your bowels (tenesmus) or that you urgently need to defecate
Cramps in your rectum
Dark spots of blood in or on your stool.
Long, thin, stringy “pencil stools”
Belly ache or bloating.
Loss of appetite and weight loss with no apparent cause
Anaemia (an abnormally low amount of red blood cells) caused by gastrointestinal haemorrhage
Is this colorectal cancer?
Many causes can produce these symptoms. Do not assume it is something insignificant, such as haemorrhoids. Check with your doctor to see what’s going on.
Your doctor will most likely perform a rectal examination. You may also undergo a sigmoidoscopy or a colonoscopy, in which your doctor inserts a long, flexible tube into your rectum to examine the insides of your intestines for malignancies or growths that could develop into cancer.
The American Cancer Society and the US Preventive Services Task Force recommend regular colorectal cancer screenings beginning at age 45 for persons who have an average risk of developing it. If you’re at a higher risk, consult your doctor about when to begin testing.
When people get diagnosed with colorectal cancer before it has spread, about 90% live at least 5 years after diagnosis, research shows.