Bowel cancer forms in the tissues of the colon (the longest part of the large intestine) or rectum (the last several inches of the large intestine before the anus). It is commonly otherwise referred to as colorectal or colon cancer.

Presenting symptoms: Blood in stools is the most commonly experienced colon cancer symptom, other symptoms may include abdominal pain and/or discomfort, pain in the back passage, unexplained weight loss, diarrhoea or constipation for no obvious reason (find out more).

UK incidence: At present, colorectal cancer is the second most common cancer in women after breast cancer whereas in men it comes as the third most common form of malignancy after prostate and lung cancer. Overall, the lifetime risk for men of being diagnosed with colorectal cancer is estimated to be one in eighteen and for women to be one in twenty. Every year, over 35,000 people are diagnosed with colorectal cancer in the UK of which about two-thirds accounts for colon and one-third for rectal cancer.

Types: Colorectal cancer comes in many forms. Most colorectal cancer are adenocarcinomas (cancer that originates in the glandular tissue). Other types include lymphoma, sarcoma, melanoma and neuroendocrine tumours (find out more). Type can also refer to the grade (how aggressive the cells look).

Risk factors: In most cases there are no predisposing risk factors but there is some evidence of associations with poor diet, smoking, excessive alcohol intake, family or personal history of colorectal cancer, lack of exercise, obesity (find out more).

Tests to determine a diagnosis and help decide on treatment options: rectal examination, Barium enema, proctoscopy, sigmoidoscopy, colonoscopy (find out more).

What determines treatment options & prognosis:

• The stage (size and spread of the tumour)
• The grade (how aggressive the cells look under a microscope)
• Age and general health

Treatment options: 

It may be classed as radical - aiming to cure or palliative - aiming to control symptoms. Options, often in combination include:

• Surgery
• Chemotherapy
• Radiotherapy (Rectal)
• Biological therapies

Further information