Colorectal Cancer and Screening Flashcards Preview

GI System > Colorectal Cancer and Screening > Flashcards

Flashcards in Colorectal Cancer and Screening Deck (19):
1

What are the risk factors for colorectal cancer?

Sporadic - 85%
Familial risk - 10%
Inheritable conditions - HNPCC
Underlying IBD - 1%

2

What are the risk factors for sporadic cases of colorectal cancer?

Age
Male
Previous adenoma/CRC
Environment - Diet, Obseity & Smoking

3

Where do a majority of CRCs arise from?

Pre-existing polyps

4

What is the origin of adenomas?

Epithelial

5

What are the two main histological types of adenomas?

Tubular
Villous
*Intermediate one is tubulovillous*

6

What are the presentations of colorectal cancer? (6)

Rectal bleeding
Altered bowel opening
Iron Deficiency Anaemia
Palpable mass
Acute colonic obstruction if stenosing tumour
Systemic symptoms of malignancy

7

What are the investigation for CRC?

Colonoscopy + biopsy
Radiological imaging

8

What are the four classifications of Duke's Criteria?

A - Confined to mucosa
B - Extended through mucosa to the muscle layer
C - Lymph nodes
D - Metastatases

9

What are the treatment options for CRC?

Surgery
Colostomy
Radiotherapy
Chemotherapy
Lymph node removal
Partial hepactectomy for metastases

10

What are the different types of screening modalities for the general population?

FOBT
FIT
Flexible Sigmoidoscopy
Colonoscopy
CT Colonography

11

What high risk groups should be especially screened?

Heritable conditions - FAP/HNPCC
Inflammatory bowel
Familial risk
Previous adenomas/CRC

12

What is FAP and what type of condition is it?

Familial Adenomatous Polyposis
Autosomal dominant

13

How does FAP present and what happens in early adulthood?

Multiple (>100) adenomas throughout the colon
High risk of malignant change

14

What are the extracolonic manifestations of FAP?

Benign gastric fundic cystic hyperplastic
Duodenal adenomas

15

What is CHRPE?

Congenital Retinal Hypertrophy of the Pigment Epithelia

16

What benefits do NSAIDs have in chemoprevention?

Reduces polyp number
Prevents recurrence of higher-grade adenomas in the retained rectal segment

17

What is HNPCC?

Hereditary Non-Polyposis Colorectal Cancer

18

What has happenned in HNPCC and what type of condition is it?

Mutation in DNA mismatch repair
Autosomal dominant condition

19

What do tumours typically have?

A molecular characteristic called microsatellite instability (MSI) - frequent mutations in short repeated DNA sequences (microsatellites)