FN: GI Polyps

Question 1

Inflammatory Pseudopolyps

Answer 1

Regenerating islands of mucosa in UC

Question 2

Hyperplastic Polyps

Answer 2

1. Piling up of goblet cells and absorptive cells
2. Serrated surface architecture
3. No malignant potential

Question 3

Hamartomatous

Answer 3

1. Tumour-like growths composed of tissues present at site where they develop
2. Sporadic or part of familial syndromes
3. Juvenile polyp: solitary hamartoma in children “cheery on a stalk”

Question 4

Neoplastic

Answer 4

1. Tubular or villous adenomas
2. usually asympto
3. May have blood/mucus PR, tenesmus

Question 5

Other Hamartomatous Polyposis Sundromes

Answer 5

Juvenile Polyposis

Cowden syndrome

Question 6

Juvenile

Answer 6

Autosomal dominant
>10 hamartomatous polyps
raised CRC risk: need surveilland and polypectomy

Question 7

Cowden syndrome

Answer 7

auto dominant
Macrocephaly + skin stigmata
Intestinal hamrtomas
Raised risk of extra-intestinal Ca

Question 8

FAP

Answer 8

Autosomal dominant

APC gene on 5q21

Question 9

FAP presentation

Answer 9

100-1000s of adenomas by 16yrs

• mainly in large bowel
• Also stomach and duodenum (near ampulla)

Question 10

FAP prognosis

Answer 10

100% develop CRC, often by 40yrs

Question 11

FAP association

Answer 11

With congenital hypertrophy of the retinal pigment epithelium (CHPRE)

Question 12

FAP Mx

Answer 12

1. Prophylactic colectomy before 20 yrs
2. total colectomy + IRA : requires life-long stump surveillance
3. Proctocolectmy + IPAA
4. Remain @ risk of Ca in stomach and duodenum: regular endoscopic screening

Question 13

HNPCC

Answer 13

Autosomal dominan
Mutation of mismatch repair enzyymes e.g. MSH2 on Chr 2p
Commonest cause of hereditary CRC: 3% of all CRC

Question 14

HNPCC presentation

Answer 14

Lynch 1: right sided CRC

Lynch 2: CRC + gastric, endometrial, prostate, breast

Question 15

Diagnosis 3,2,1 rule

Answer 15

> 3 family members over 2 generations with one

Question 16

Peutz-jeghers syndome

Answer 16

autosomal dominant

STK11 muttions

Question 17

Peutz-jeghers presentation

Answer 17

1. 10-15 yrs
2. Mucocutaneous hyperpigmentation: macules on palms, buccal mucosa
3. Multiple GI hamartomatous polyps
   - Intussusception
   - Haemorrhage
4. Raised Ca risk
   - CRC, pancreas, breast, lung, ovaries, uterus