Case 1 - colon cancer

Question 1

What happens to glandular structures in colon cancer?

Answer 1

irregular glands permeate the stroma

Question 2

What does well differentiated mean in histology?

Answer 2

the cells are behaving well

look normal, with defined glands resembling normal colon tissue (or wherever it is)

Question 3

What is the significance of poor differentiation in histology?

Answer 3

poor prognostic factor
might not have any glands if in the colon, this is not good

thinking cancer

Question 4

What are the stages to Dukes classification?

Answer 4

A
B
C1
C2

Question 5

What is Dukes classification A?

Answer 5

Tumour confined to bowel wall

Nodes negative

Question 6

What is Duke classification B?

Answer 6

Tumour spread beyond muscle

nodes negative

Question 7

What is Dukes classification C1?

Answer 7

Lymph nodes positive

highest node spared

Question 8

What is Dukes classification C2?

Answer 8

Highest node involved

Question 9

What might you give someone with lymphoblastic invasion?

Answer 9

adjuvant chemo

Question 10

What might necrosis in histology be accounted to?

Answer 10

chemotherapy!

Question 11

What immunohistochemical tests tell us that a tumour if from the bowel?

Answer 11

CK20

CDX2

Question 12

How would a bowel cancer test for CK7?

Answer 12

negative

Question 13

What molecular tests are required before any chemo treatment for colon cancer?

Answer 13

microsatellite satbility
aneuploidy
allelic losses
(some others)
KRAS
TP53
mismatch repair proteins
RAS
BRAF

Question 14

What happens if a tumour shows loss of MMR proteins?

Answer 14

this is good!!

Question 15

What is Lynch syndrome?

Answer 15

inherited disorder predisposing to cancer

Question 16

What are the possible results for MMR loss?

Answer 16

loss of MLH1 + PMS2

loss of MSH2 + MSH6

Question 17

What are the characters of MSI-H tumours?

Answer 17

proximal colon
poorly differentiated
mucinous histology
increased lymphocytic infiltration

Question 18

What are the 2 types of MSI-H tuours?

Answer 18

Sporadic

Lynch Syndrome

Question 19

What proportion of MSI-H tumours are sporadic?

Answer 19

15%

Question 20

Which of Sporadic or lynch syndrome MSI-H tumours are more aggressive?

Answer 20

Lynch Syndrome

Question 21

What must you do when you identify a Lynch Syndrome MSI-H cancer?

Answer 21

alert patient / blood relatives

Question 22

How is lynch syndrome inherited?

Where in the GIT does it present?

Answer 22

AD
germline mutations of one of the MMR genes
right colon

Question 23

loss of MLH1
Braf mutated
MLH1 promoter methylated

What is this?

Answer 23

sporadic MSI-H tumour

Question 24

Loss of MLH1
Braf not mutated
No MLH1 promoter methylation

What is this?

Answer 24

Lynch syndrome MSI-H tumour

Question 25

Loss of MSH2 and MSH6

what is this?

Answer 25

Lynch Syndrome MSI-H tumour

Question 26

How are must metastatic colon cancers treated?

Answer 26

EGFR antibodies (panitumumab, cetuximab)

Question 27

Which patients would you not give EGFR antibodies to?

Answer 27

patients with tumours with RAS mutations

Question 28

IS a BRAF mutation a good or bad thing in colon cnacer?

Answer 28

bad thing, very bad!!!!!

poor prognostic marker

Question 29

Are cancers more common in UC or Crohns?

Answer 29

UC

Question 30

Where would most cancers in UC occur?

Answer 30

near the end of the colon

Question 31

The presence of what cell type in colonic mucous would suggest UC?

Answer 31

neutrophils