Colorectal Cancer

Key facts

• Colorectal cancer develops in the lining of the colon or rectum and is one of the most common cancers worldwide.
• Risk rises with age, and a low-fibre diet, obesity, smoking, heavy alcohol use, and a family history of the disease are established risk factors.
• Treatment depends on how far the cancer has spread: surgery to remove the tumour is usually central to early-stage care, and chemotherapy, including the oral agent capecitabine, is added before or after surgery or as the main treatment when the cancer has spread.
• Any new or persistent change in bowel habits, blood in the stool, unexplained weight loss, or ongoing abdominal discomfort warrants prompt medical assessment.

What raises the risk

Colorectal cancer becomes more common with age, and risk is higher with a diet low in fibre and high in processed or red meat, obesity, smoking, heavy alcohol use, and a personal or family history of colorectal polyps or cancer. Inflammatory bowel disease also raises risk over time. Screening programmes using stool tests or colonoscopy catch many cases early, when treatment is most effective.

How colorectal cancer is managed

Treatment depends on how far the cancer has spread. Surgery to remove the tumour is usually central to early-stage care. Chemotherapy is added before surgery to shrink a tumour, after surgery to reduce the risk of it returning, or as the main treatment when the cancer has already spread.

Oral chemotherapy is a common part of many regimens. Capecitabine is one of the most widely used agents; the body converts it into fluorouracil at the tumour site, which limits damage to healthy tissue compared with intravenous alternatives. It is often used alongside other medicines or radiotherapy as part of oncology support care.

When to see a doctor

Any new or persistent change in bowel habits, blood in the stool, unexplained weight loss, or ongoing abdominal discomfort warrants prompt medical assessment. Anyone with a family history of colorectal cancer or inflammatory bowel disease should discuss screening timing with a doctor.

This page is educational and does not replace advice from a doctor or pharmacist who knows your health history.