Introduction Colorectal tumours can be benign (e.g., polyps) or malignant (e.g., colorectal carcinoma). The colon and rectum are common sites for cancer development, often from precursor adenomatous polyps. Risk Factors Age: Incidence increases over 50. Family history of colorectal cancer or polyps. Hereditary conditions: Familial adenomatous polyposis (FAP), Lynch syndrome. Inflammatory bowel diseases: Ulcerative colitis, Crohn’s disease. Diet: High in red/processed meat, low in fibre. Classification Adenomas: Precancerous polyps. Can be tubular, tubulovillous, or villous. Colorectal Carcinoma: Most are adenocarcinomas (~95%). Clinical Presentation Change in bowel habits: Diarrhoea, constipation. Rectal bleeding or melaena. Abdominal pain. Unintended weight loss and fatigue. Iron-deficiency anaemia. Palpable abdominal mass or rectal mass. Investigations Colonoscopy with biopsy: Gold standard. Flexible sigmoidoscopy. Faecal occult blood test (FOBT): Screening. CT colonography. CT, MRI for staging and assessing metastasis. Management Surgery: Primary treatment for localized tumours. Chemotherapy: Adjuvant or for metastatic disease. Radiotherapy: Particularly for rectal tumours. Endoscopic removal for early, small tumours or polyps. Prognosis Depends on the stage at diagnosis and the presence of metastasis. Regular monitoring and follow-up colonoscopies are essential. Prevention Regular screening, especially in those over 50 or with risk factors. Dietary modifications: Increase fibre intake, reduce red/processed meat.
