pathology of tumours of the lower GIT

Question 1

bowel cancer is a disease of older age T or F?

Answer 1

true

Question 2

what intervention has reduced mortality from bowel cancer?

Answer 2

endoscopy

Question 3

At the age of 60, what proportion of people have bowel polyps?

Answer 3

1/3

Question 4

what are the origins of colorectal adenocarcinoma?

Answer 4

Dysplasia of the epithelium - adenoma

Question 5

what hereditary condition predisposes to adenocarcinoma of the bowel?

Answer 5

familial adenomatous polyposis

Question 6

would you need to offer to screen the family if a member had familial adenomatous polyposis?

Answer 6

yes

Question 7

what is the pathophysiology of hereditary nonpolyposis colorectal cancer HNPCC?

Answer 7

mutations occur in genes that code for repair proteins - there are two hits of both genes in a pair before colorectal cancer develops

Question 8

why is it important to identify HNPCC cancers?

Answer 8

there is a risk of further cancers in the index pt and relatives
some chemo will not work on them, eg flurouracil - DNA damage is not recognised and so apoptosis is not activated

Question 9

where do most colorectal cancers occur?

Answer 9

rectum, rectosigmoidal junction and anus - combined = 38%

Question 10

what is resection coding?

Answer 10

gives an indication to a surgeon as to whether the tumour has been completely excised or whether the resection margin still has tumour present on it
R0 - tumour completely excised locally
R1 - microscopic involement of margin by tumours
macroscopic involvement of margin by tumour

Question 11

how does prognosis relate to circumferential resection margin?

Answer 11

there is a higher risk of recurrence if there is a positive CRM (ie cancer is present in the margin of the resection)

Question 12

what is a high tie lymph node?

Answer 12

the lymph node furthest away that was removed by the surgeon

Question 13

a tumour has not yet penetrated the muscularis mucosa from the mucosa, what Dukes’ and TNM staging is this?

Answer 13

Dukes’ doesn’t have anything for carcinoma in situ

pTispN0

Question 14

if the tumour of the bowel has invaded the muscularis mucosa what would be the Dukes’ and TNM staging?

Answer 14

Dukes’ A

pT1pN0

Question 15

if the tumour of the bowel has invaded the muscularis mucosa and the submucosa what would be the Dukes’ and TNM staging?

Answer 15

Dukes’ A

pT1pN0

Question 16

if a tumour has invaded the muscularis propria what is its Dukes’ and TNM stage?

Answer 16

Dukes’ A

pT2pN0

Question 17

if the tumour has gone through the muscularis propria - ie through the bowel wall, what dukes’ and TNM stage is it?

Answer 17

Dukes’ B

pT3pN0

Question 18

if the tumour has gone to a set of regional lymph nodes, what is the dukes and TNM staging?

Answer 18

Dukes’ C1

pT3pN1

Question 19

if the tumour has gone to two sets of lymph nodes, what is the dukes and TNM staging?

Answer 19

Dukes’ C2

pT3pN2

Question 20

Summarise the Duke’s staging

Answer 20

Dukes A: invasion into but not through the bowel wall (90% 5 year survival)
Dukes B: invasion through the bowel wall but not involving lymph nodes (75% 5 year survival)
Dukes C: involvement of lymph nodes (35% 5 year survival)
Dukes D: widespread metastases (25% 5 yr survival)

Question 21

what is the trend of the five year survival rate of colon caner over the last 40 years?

Answer 21

the five year survival is increasing

Question 22

what is the treatment for adenoma?

Answer 22

endoscopic resection

Question 23

what is the treatment for colorectal adenocarcinoma?

Answer 23

surgical resection

Question 24

What is the treatment for metastatic colorectal adenocarcinoma?

Answer 24

chemo

palliative care