Colon pathology

Question 1

what is a polyp

Answer 1

a tumour (swelling) protrusion above an epithelial surface

Question 2

what are the differential diagnosis’s of colonic polyps

Answer 2

1. adenoma
2. serrated polyp
3. polypoid carcinoma
4. other

Question 3

what are the two types of polyp

Answer 3

epithelial

mesenchymal

Question 4

what are the diff types (2) and examples of epithelial polyp

Answer 4

benign:
neoplastic (adenoma)
inflammatory
hamartomatous
metaplastic

malignant:
polypoid (adenocarcinomas)
carcinoid polyps

Question 5

adenoma of colon….

Answer 5

benign and non-invasive, do not metastasise

Question 6

all _____ are dysplastic

Answer 6

adenomas

Question 7

what is the progression from benign to malignant

Answer 7

normal mucosa -> adenoma (dysplastic) -> adenocarcinoma (invasive)

Question 8

why must all adenomas be removed and how it is done

Answer 8

because they are all premalignant

endoscopically or surgically

Question 9

how is adenocarcinoma treated

Answer 9

colon/rectum is removed and sent to pathology for staging

Question 10

how is colorectal carcinoma staged?

Answer 10

dukes staging and TNM staging predicts prognosis

Question 11

confined by muscularis propria

Answer 11

dukes A (T1 or T2, N0)

Question 12

through muscular propria

Answer 12

dukes B (T3 or T4, N0)

Question 13

metastatic to lymph nodes

Answer 13

Duke C (any T, N1 or N2)

Question 14

left sided colorectal carcinoma makes up __% of tract and what structures does this include

Answer 14

75%

rectum, sigmoid and descending

Question 15

right sided colorectal carcinoma makes up ___% of tract including ___ and ____

Answer 15

25%

caecum and ascending

Question 16

p/c of left sided colorectal carcinoma

Answer 16

blood PR, altered bowel habit, obstruction

Question 17

p/c right sided

Answer 17

anaemia, weight loss

Question 18

what are the varied gross appearances of colorectal carcinoma

Answer 18

polypoid, structuring, ulcerating

Question 19

what is the pattern of spread of local invasion colorectal cancers

Answer 19

mesorectum, peritoneum, other organs

Question 20

what is the lymphatic spread of cancers

Answer 20

mesenteric nodes

Question 21

what is the haematogenous spread of carcinomas

Answer 21

liver, distant sites

Question 22

what are the two inherited cancer syndromes

Answer 22

hereditary: non polyposis, Coli (HNPCC) - <100 polyps

familial - adenomatous, polyposis (FAP) - >100 polyps

Question 23

difference between HNPCC and FAP

Answer 23

HNPCC:
late onset
autosomal dominant
defect in DNA mismatch repair
inherited mutation in MLH-1, MSH-2, PMS-1 or MSH-6 genes
right sided tumours
<100 polyps
mucinous tumours
crowns like inflammatory response
assoc with gastric and endometrial carcinoma

FAP:
early onset
autosomal dominant
defect in tumour suppression
inherited mutation in FAP gene
throughout colon 
> 100 polyps
adenocarcinoma NOS
no specific inflammatory response
assoc with Desmoid tumours and thyroid carcinoma