Colon polyps and neoplasms [3]

Question 1

Non neoplastic polyps

Answer 1

inflammatory polyps
Hamartomatous polyps
- Juvenile
- peutz jeghers
Hyperplastic polyps

Question 2

Hamartomatous polyps

• what
• who

Answer 2

“tumor like” overgrowth where it is normally present.
- risk for GI carcinoma

Mostly occuring in childhood (pre-pubertal)

Juvenile + peutz jeghers type

Question 3

peutz jeghers syndrome (Hamartomatous polyps)
median age
GI lesions
cancer risk

Answer 3

10-15
arborizing polyps:
SI>colon>stomach

Colonic adenocarcinoma

Question 4

juvenile polyps (hamartomatous)
median age
GI lesions
cancer risk

Question 5

Hyperplastic polyps
median age
sessile or peduncular?
GI lesions
cancer risk
architecture

Answer 5

increase with age
sessile
Commonly seen in left sided  colon/rectum
No dysplasia (but SSP are premalignant)
star shaped

Question 6

Serrated polyps/adenoma

Answer 6

right side of colon most common 
- (*hyperplastic is Left)
serrated architecture
Dysplastic epithelium may be present 
DEFINITELY can progress to adenocarcinoma

Question 7

What features of neoplastic polyps confer increased risk for malignancy?

Answer 7

size matters! bigger = bigger risk of malignancy
increase with age (50% by age 50)
presence of high grade dysplasia

Question 8

adenomatous changes

Answer 8

1. cells
   - no respect 4 boundary - piling on eachother
2. Nuclei
   - darker
   - lose basal orientation
3. cytoplasm ↓: N↑
4. mitotic figures

Question 9

4 molecular pathway abberation associated with colon cancer

Answer 9

WNT/APC/Beta catenin pathway

- mut in APC at 5q21 → mutation of APC can no longer form complex to degrade beta catenin

Question 10

Does adenoma formation represent increase in the rate of cell proliferation in early stage of polyp formation?

Answer 10

no.

polyps represent an increase in the size of the proliferating crypt compartment

Question 11

APC mutations can run in families, producing _______.

Answer 11

Familial adenomatous polyposis
FAP pts have increased risk of colon cancer, but accounts for small fraction of total case of colon cancer

(but if you have FAP autosomal dominant germline mut of APC gene, youre screwed, 100% will get invasive adenocarcinoma b4 age 30)

Question 12

Microsatellite instability

Answer 12

defects in mismatch repair proteins

Question 13

If pt has KRas/MAP kinase/PI3 kinase WT, what can you treat the GI cancer with?

Answer 13

FOLFOX + cetuximab (against Epidermal growth factor)

Question 14

Risk factors for colorectal carcinoma

Answer 14

Strong:
advanced age
country of birth
FAP/HNPCC
Long standing UC

Mod:
high red meat, prev cancer, high fat, smoking, alcohol, obesity, cholecystectomy

Question 15

Protective factors for colorectal carcinoma

Answer 15

high physical activity
Aspirin + NSAID use
High vegetable/fruit diet
high fiber, high Ca2+

Question 16

Hereditary non-polyposis colorectal cancer (HNPCC) aka

Answer 16

Lynch syndrome

Indiv more at risk and develop colon cancer at earlier stage
Right sided usually
Due to inherited mutation of mismatch repair gene allele → 2nd allele mutation over time leading to microsatellite instability

Question 17

colon cancers most commonly metastasize to ____

Answer 17

liver