Benign large bowel neoplasms

Epidemiology:

• Up to 10% of the Western world’s population may have a benign tumour(s)

Pathological features:

• Adenomas are the most common and important benign large bowel neoplasms.
• Arise from glandular or epithelial cells
• The tumour is most often a polyp with a stalk but flat (sessile) lesions also occur
• May be single or multiple (and in the polyposis syndromes, hundreds may be present)

Classification of colorectal polyps:

1. Neoplastic:

• Adenoma
• Tubular
• Tubulovillous
• Villous

2. Non-neoplastic:

• Hamartoma
• Juvenile
• Peutz-Jegher’s
• Inflammatory
• Lymphoid
• Inflammatory

• Miscellaneous
• Metaplastic
• Connective tissue polyps

Clinical features:

• Most adenomas are asymptomatic and devoid of signs
• Dx is usually made either as the result of a screening programme or on incidental examination of the large bowel by colonoscopy or Barium enema

Management:

The finding of an adenomatous polyp (particularly if > 1cm) requires the following action:

• Complete examination of the large bowel by colonoscopy to exclude or identify other similar neoplasms
• Removal of all lesions (usually endoscopically)
• Regular lifelong surveillance for recurrence and/or development of large bowel cancer