Colonic Polyps

Question 1

def

Answer 1

protuberance into the lumen from the normally flat colonic mucosa

Question 2

aetiology

Answer 2

1 neoplastic
-adenomas (2/3 of all CP)
-adenocarcinomas
2 non-neoplastic
-hyperplastic polyps
-inflammatory pseudopolyps (IBD)

Question 3

multiple colonic polyps

Answer 3

occur in familial adenomatous polyposis (FAP) & its variants:

• turcots syndrome (FAP plus glioblastomas or medulloblastomas)
• gardners syndrome (FAP plus osteomas or soft-tissue tumours or sebaceous cysts)

are autosomal dominant diseases caused by mutations in adenomatous polyposis coli (APC) gene

Question 4

epi

Answer 4

common
>50% in over 60yrs
FAP in 1/20,000

Question 5

history

Answer 5

usually asymptomatic
change in bowel habit 
tenesmus
diarrhoea
PR bleeding with polyp ulceration
symptoms of anaemia

Question 6

what is the definition of tenesmus

Answer 6

recurring need to evacuate the bowels rapidly

Question 7

examination

Answer 7

usually no findings

may be palpable on PR if low in rectum

Question 8

investigations

Answer 8

1 bloods
-FBC for microcytic anaemia
2 stool
-blood in stool
3 endoscopy
-colonoscopy is gold standard
-polyps histologically examined to determine malignant potential

Question 9

management

Answer 9

for small isolated polyps - colonoscopic polypectomy
for large isolated polyps - surgical resection
for multiple polyposis syndromes (esp FAP) - early colectomy is recommended to reduce risk of malignancy

arrange follow-ups

Question 10

complicatiosn

Answer 10

malignant change (highest risk in villous adenomas & multiple polyposis syndromes)
risk of bowel obstruction with very large polyps

Question 11

prognosis

Answer 11

good if detected & treated before malignant change