Pathology of Colorectal Carcinoma

Question 1

what is a polyp

Answer 1

a protrusion above an epithelial surface

a tumour - does not indicate benign or malignant

Question 2

differential diagnosis of polyp

Answer 2

adenoma
serrated poylp
polypoid carcinoma
other

Question 3

macroscopic appearance of polyps

Answer 3

pedunculate 
sessile
flat
irregular surface 
long stalk

Question 4

describe adenoma of colon

Answer 4

benign tumour - not invasive, does not metastasise
common
dysplastic
can develop to adenocarcinoma (malignant)

Question 5

microscopic changes of adenoma of colon

Answer 5

tubullovillous
tubular
villous

Question 6

treatment of adenomas

Answer 6

must be removed as they are always premalignant

via endoscopically or surgically

Question 7

molecular genetic origins of colorectal adenomas

Answer 7

do not all have the same molecular genetic origins - separate pathways for inherited tumours and serrated adenomas

Question 8

treatment of adenocarcinoma

Answer 8

surgery

Question 9

microscopic changes in adenocarcinoma

Answer 9

tumour invades muscularis propria

moderately differentiated

Question 10

staging of colorectal carcinoma

Answer 10

dukes staging - predicts prognosis

Question 11

Dukes staging A

Answer 11

confined by muscularis proprietary

Question 12

Dukes staging B

Answer 12

throughout muscularis propria

Question 13

Dukes staging C

Answer 13

metastatic to lymph nodes

Question 14

left sided colorectal carcinoma

Answer 14

includes the rectum, sigmoid and descending colon

Question 15

symptoms and signs of left sided colorectal carcinoma

Answer 15

hypertension
altered bowel habits
obstruction

Question 16

right sided colorectal carcinoma

Answer 16

includes the caecum and ascending colon

Question 17

symptoms and signs of right sided colorectal carcinoma

Answer 17

anaemia

weight loss

Question 18

pathology of colorectal carcinoma

Answer 18

varied gross appearance - polyploid, structuring, ulcerating
typical histopathological appearance

Question 19

patterns of spread of colorectal carcinoma

Answer 19

local invasion
lymphatic spread
haematogenous

Question 20

local invasion of colorectal carcinoma

Answer 20

mesorectum
peritoneum
other organs

Question 21

lymphatic spread of colorectal carcinoma

Answer 21

mesenteric nodes

Question 22

inherited cancer syndromes

Answer 22

hereditary non polyposis coli

familial adenomatous polyposis

Question 23

describe hereditary non polyposis coli

Answer 23

late onset

autosomal dominant - defect in DNA mismatch repair

Question 24

mutation in hereditary non polyposis coli

Answer 24

MLH-1, MSH-2, PMS-1 or MSH-6 genes

Question 25

describe familial adenomatous polyposis

Answer 25

early onset

autosomal dominant - defect in tumour suppression

Question 26

mutation in familial adenomatous polyposis

Answer 26

FAP gene

Question 27

tumours of hereditary non polyposis coli

Answer 27

right sided 
< 100 polyps 
mucinous tumours 
Crohn’s like Inflammatory response
Associated with gastric and endometrial carcinoma

Question 28

tumours of familial adenomatous polyposis

Answer 28

throughout colon
>100 polyps
Adenocarcinoma NOS
No specific inflammatory response
Associated with desmoid tumours and thyroid carcinoma