Large Bowel Neoplasm

Question 1

risk factors for CRC

Answer 1

caloric intake, obesity, red meat consumption, alcohol consumption, smoking, sedentary lifestyle

Question 2

FAP

Answer 2

familial adenomatous polyposis

• autosomal dom
• mutation in APC gene 5q21
  tx: will develop CRC, prophylactic surgery @ dx or b/f age 20

Question 3

MYH polyposis

Answer 3

autosomal recessive
mutation in base excision repair gene
cancers are mostly in ascending/right-sided colon

Question 4

HNPCC/Lynch Syndrome

Answer 4

most common inherited colon cancer syndrome
autosomal dominant
germline mutation in mismatch repair genes (MMR)
60-80% chance of colon cancer
accelerated polyp-cancer sequence
proximal/right sided colon

Question 5

criteria for HNPCC

Answer 5

no specific markers
3-2-1 rule
- 3 or more relatives w/ HNPCC assoc cancer
- 2 or more successive generations
- 1 or more relative dx b/f age 50

Question 6

tubular adenoma

Answer 6

most common type of polyp
usually pedunculated/on a stalk
less likely to become malignant

Question 7

villous adenoma

Answer 7

uncommon, but more likely to harbor adenoma

frond-like villiform extensions

Question 8

hyperplastic polyp

Answer 8

non-neoplastic polyp
small, sessile
common in rectum/sigmoid

Question 9

juvenile polyp

Answer 9

non-neoplastic polyp

in children <5yo

Question 10

Peutz-Jegher polyp

Answer 10

hamartomatous
branching smooth muscle cells lined by goblet cells
slight malignant potential