colorectal CA Flashcards
DDx of BRBPR (4)
- hemmoroids
2. proctiis (IBD)
3. polyps
4. CA
*** what is important about hemmooids
diagnosis of exclusion - need to rule out all others
what is important in workup of anemia
scope
what is only way to say lesion is not malig.
look under a microscpe
what is part of blood supply to colon that systemic
middle and inferior rectal
epi
3rd most common CA
- 12% of all CA in ont.
- male>female
- 1/3 local, 1/3 regional, 1/4 mets
sporadic causes (majority
- AGE
- men
- env. (diet, obese, DM)
- personal Hx of CRC or polyps
- fam. Hx
- IBD
3 known hereditary
- HNPCC
- FAP
- MYH polyposis
what is precursor to CA
adenoma that can then be removed- target for screenign
what is tubular adenoma
adenomatous epi with a stalk
what is villous adenoma
sessile ( no stalk) with finger-like projections
2 features of high grade dysplasia
- nuclear atypia
2. architectural complexity
WHO definition
metastitis (carcinoma def.) of the colon and rectum requires invasion of the muscilaris mucosa into the submucosa
3 variants
- mucinous - > 50% of lesion has extracellula mucin epithelium
- signet ring cell - > 50% with prominent intracytoplasmic mucin
- other rare types
2 grade types
low - 50-100% gland formation
high - 0-49% gland formation
3 margins
- proximal
2 distal - radial - around fatty edge
what is problematic margins
1mm is same as being at the edge
2 types of polyps
neoplastic and non
3 non-neoplastics
- hyperplastic
- inflammatory
- juvenile
3 neoplastic
- adenomatous - all dysplastic
- serrated
- hamarotomatous
3 types of adenomatous polyps
- pedunclulated
- sessile or tubular
- villous
epi of adenomatous polyps
v. common
- 1/4 will become CA
- need to be removed
what is FAP
1-2% of patients with CRC
- develop in teens
- carpet of polyps
- APC gene mutation
- ALL NEED prophylactic colectomy
what is attenuarted FAP
- later age
- less polyps
- may spare rectum
- same APC, but point mutation
what is HNPCC
3% of all CRC - other associated CAs 3,2,1 rule - 3 relatives, 2 gens, 1 first degree - mismatch repair gene mutation - 80% risk of CRC
screening for avg.
- no family Hx, or over 60
@ 50, scope q10 years
annual FOBT
screening for moderate risk
fam Hx, or 1st degree relative
screening for FAP
scope annually in teens until surg
screen for HNPCC
scope biannually from 20-25 and annually from 40 onward
screen for IBD
scope q 1-2 years after 8 years of colitis
5 common presentations of CRC
- BRBPR
- change in bower habits
- abdo pain or mass
- weight loss
- anemia
diagnosis
scope with biopsy
***best predictor of survival
nodal status
what is treatment
curable - surg with 5cm margins
node + - adjuvant chemo
incurable - chemo
what is treatment for incurable
chemo and pallaitice surgery or stents
what is done for survors
- followed 5-10 years
- scopes q 1,3,5 years
- CEA q 6 months
