Bowel cancer Flashcards
General Info
3rd most common cancer
High incidence in western world
Risk factors
Migrating from low to high risk area Red meat Fats Low vegetables/fruit/fibre No physical activity High BMI UC/Crohn's Adenoma in large bowel Family history Old age
Advantage of high fibre diet
More short chain fatty acids - healthy gut bacteria - less proliferation of neoplastic cells
Increased stool bulk transit time
Reduces formation of secondary bile acids
Pathological Features of polyps
Goblet cells
Tubular adenoma
Villous adenoma
Tubulovillous
Symptoms
Asymptomatic, change in bowel habit, bleeding, anaemia, abdo pain
Tests/diagnosis
CT colonography
MRI for rectal cancer
CT scan for distal metastasis
Biopsy
Screening
Stool test or FIT (tests for blood in stool) - antibody-antigen reaction
Not specific
Flexible sigmoidoscopy, colonoscopy
Lynch Syndrome
Affects caecum and right colon
DNA pairs mismatch, and there are errors in mismatch repair genes -> micro satellites form and cause instability
Assess using Amsterdam criteria - multiple relatives…
Familial Adenomatous Polyposis
Autosomal dominant
Patients acquire first hit in utero
