Colon cancer

Question 1

superior hemorhoidal / rectal arteries arise from which artery?

Answer 1

IMA

Question 2

lower rectal cancer will have more systemic or localized spread?

Answer 2

systemic

Question 3

in which layer of the GI tube are the lymphatics located?

Answer 3

submucosal

Question 4

what are protective factors limiting colon cancer?

Answer 4

hormone replacement
NSAID use
fiber, fruits, vegetables

Question 5

what type of gene is APC?

Answer 5

tumor suppressor

Question 6

what type of gene is K-RAS?

Answer 6

proto oncogene

Question 7

what type of gene is DCC?

Answer 7

tumor suppressor

Question 8

what type of gene is p53?

Answer 8

tumor suppressor

Question 9

what is the sequence of gene mutations leading to carcinoma?

Answer 9

APC - K-RAS - DCC - p53

Question 10

what is the mutation in FAP? which chromosome?

Answer 10

APC gene

chromosome 5q

Question 11

what is the inheritance of FAP?

Answer 11

autosomal dominant

Question 12

what is the lifetime cancer risk by age 50 for FAP?

Answer 12

100%

Question 13

what is the treatment for FAP?

Answer 13

total colectomy and rectum

Question 14

what is the pathogenesis of lynch syndrome?

Answer 14

mismatch repair gene defects

Question 15

how does lynch syndrome differ from FAP?

Answer 15

progression to cancer is quick with lynch

Question 16

which gene is responsible for development of early adenoma?

Answer 16

APC

Question 17

which gene is responsible for development of intermediate adenoma?

Answer 17

K-RAS

Question 18

which gene is responsible for development of late adenoma?

Answer 18

DCC

Question 19

which gene is responsible for development of colon carcinoma?

Answer 19

p53

Question 20

advanced polyps may produce what screening sign?

Answer 20

positive fecal occult blood test

Question 21

what are the screening modalities for colon cancer? what is the gold standard?

Answer 21

colonoscopy 
flexible sigmoidoscopy 
high sensitivity guaiac / FOBT 
double contrast barium enema 
CT colonoscopy 

GOLD STANDARD: colonoscopy

Question 22

colonoscopy scope can reach how far?

Answer 22

cecum and terminal ileum

Question 23

sigmoidoscopy scope can reach how far?

Answer 23

splenic flexure

Question 24

what does a stool guaiac blood test assay for?

Answer 24

peroxidase activity

Question 25

what does a fecal immunochemical test assay for?

Answer 25

antibody

Question 26

a positive stool-based test requires what next step?

Answer 26

colonoscopy

Question 27

a positive double contrast barium enema requires what next step?

Answer 27

colonoscopy

Question 28

what are the screening regimens for colon cancer?

Answer 28

colonoscopy every 10y, or flexible sigmoidoscopy every 5y plus high sensitivity FOBT every 3 years, or high sensitivity FOBT every year

Question 29

if a patient has family hx of colon cancer when does colonoscopy start? when are they repeated?

Answer 29

age 40 repeat every 5 years

Question 30

when do patients with IBD get screened for colon cancer? what else is done? how often is the screening?

Answer 30

colonoscopy every 8-10 years after symptoms collect 4x random biopsies every 10cm repeat every 1-2 years

Question 31

when do patients with lynch syndrome get screened for colon cancer? when is it repeated?

Answer 31

colonoscopy age 20-25 repeat 1-2 years

Question 32

when do patients with FAP get screened for colon cancer? when is it repeated?

Answer 32

colonoscopy age 10-12 repeat 1-2 years

Question 33

what is the serum tumor marker for colon cancer?

Answer 33

CEA

Question 34

what test should be used for equivocal CT findings?

Answer 34

PET

Question 35

what staging is Tis?

Answer 35

intraepithelial

Question 36

what staging is T1?

Answer 36

muscularis mucosa into submucosa

Question 37

what staging is T2?

Answer 37

invades muscularis propria

Question 38

what staging is T3?

Answer 38

invades pericolorectal tissues

Question 39

what staging is T4a?

Answer 39

penetrates peritoneum

Question 40

what staging is T4b?

Answer 40

invades adjacent organs

Question 41

intraepithelial staging

Answer 41

Tis

Question 42

muscularis mucosa into submucosa

Answer 42

T1

Question 43

invades muscularis propria

Answer 43

T2

Question 44

invades pericolorectal tissues

Answer 44

T3

Question 45

penetrates peritoneum

Answer 45

T4a

Question 46

invades adjacent organs

Answer 46

T4b

Question 47

nodal staging N0

Answer 47

no regional node met

Question 48

nodal staging N1

Answer 48

met in 1-3 regional nodes

Question 49

nodal staging N2

Answer 49

met in 4 or more regional nodes

Question 50

how many nodes should be examined for adequate staging?

Answer 50

15

Question 51

where are nodes collected from?

Answer 51

visceral mesentery

Question 52

what are the met stagings?

Answer 52

M0 - no met M1 - distant met

Question 53

how far must resection margins be?

Answer 53

5cm

Question 54

resection is largely determined by what factor?

Answer 54

blood supply

Question 55

what is involved in a low anterior resection?

Answer 55

rectosigmoid resection extending below the peritoneal reflection with associated mesorectum

Question 56

what is involved in an abdominal perineal resection?

Answer 56

rectosigmoid resection including anal sphincters, anal opening, and associated mesorectum

Question 57

what is involved in a colectomy?

Answer 57

resected colon with associated mesentery

Question 58

T1, T2, T3 colorectal cancer are treated with what modality?

Answer 58

surgical resection

Question 59

surgical resection is indicated for what staging?

Answer 59

T1, T2, T3

Question 60

some T3, T4 colorectal cancer is treated with what modality?

Answer 60

surgical resection with chemo

Question 61

surgical resection with chemo is indicated for what staging?

Answer 61

T4, some T3 N1, N2 surgical resection with chemo

Question 62

N1, N2 colorectal cancer are treated with what modality?

Answer 62

surgical resection with chemo

Question 63

liver or lung met is treated with what modality?

Answer 63

surgical resection with chemo

Question 64

how is metastatic disease treated for colorectal cancer?

Answer 64

chemo

Question 65

what is the treatment for Tis, T1 rectal cancer?

Answer 65

transanal excision

Question 66

what is the treatment for T2 rectal cancer?

Answer 66

surgical resection

Question 67

what is the treatment for T3, T4, N plus rectal cancer?

Answer 67

neoadjuvant chemo and resection

Question 68

when is rectal cancer neoadjuvant therapy indicated?

Answer 68

T3 and T4 node-positivity locally unresectable