Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Gastrointestinal Pathology > Colorectal Cancer and Screening > Flashcards

Colorectal Cancer and Screening Flashcards

1
Q

What % of colorectal cancers are adenocarcinomas?

A

95%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What % of colorectal cancers are due to IBD?

A

1%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What inheritable conditions are related to colon cancer?

A

HNPCC (5%)
FAP < 1%
Other CRC syndromes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Risk factors for colon cancer

A 
Genetics
Age
Male 
Previous adenocarcinoma/CRC
Diet
- decreased fibre
- decreased fruit and veg 
- decreased calcium 
- increased red meat 
- increased alcohol 
Obesity
Lack of exercise
Smoking
DM
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do the majority of colorectal cancers arise from?

A

Pre-existing polyps

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Types of colorectal polyps

A

Epithelial

Mesenchymal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Histological types of colorectal adenomas

A

Tubular (75%)
Villous (10%)
Intermediate tubulovillous (15%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Molecular sequence of colorectal adeno carcinoma

A

Activation of oncogene - k-ras, c-myc
Loss of tumour suppressor gene - APC, p53, DCC
Defective DNA repair pathway genes; microsatellite instability
Cell growth proliferation apoptosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Presentation of colorectal cancer

A 
Rectal bleeding
Altered bowel opening - diarrhoea
Iron deficiency anaemia
- men of any age
- non menstruating women 
Palpable rectal or right lower abdominal mass
Acute colonic obstruction if stenosing tumour 
Weight Loss
Anorexia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Who should you investigate with specific symptoms indicative of colorectal cancer?

A

Rectal bleeding or diarrhoea

  • each symptom on its own investigation if > 60 y/o
  • combined symptoms investigate if > 40
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If non menstruating women have iron deficiency anaemia, what malignancy are they most likely to get?

A

Right sided colonic malignancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Investigation for colon cancer

A

Colonoscopy
Barium enema
CT colonography
Ionising radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Risks of colonoscopy

A

Perforation
Bleeding
Can exacerbate renal failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Prevention of colorectal cancer

A

Lose weight
Exercise
Fruit and Veg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Who is screened for colon cancer?

A

Average risk population

High risk groups

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Aim of population screening

A

Detect pre-malignancy adenomas/early cancer in the general population

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What tests are done for the population screening of colon cancer?

A 
FOBT
FIT
Flexible sigmoidoscopy 
Colonoscopy 
CT colonography
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does FOBT stand for?

A

Faecal occult blood test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does FIT stand for?

A

Faecal immunochemical test

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why would a flexible sigmoidoscopy be done in population screening for colon cancer?

A

2/3rds of cancer are in the left colon so can do a more focused search in just in that area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Features of Scottish bowel screening programme

A

Age 50 - 74 days
FOBT every 2 years
FOBT positive => colonoscopy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What % does Scottish bowel screening programme give a reduction of risk in colorectal cancer mortality?

A

15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Heritable conditions for colorectal cancer

A

FAP

HNPCC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does FAP stand for?

A

Familial adenomatous polyposis

25
Q

What HNPCC stand for?

A

Hereditary non polyposis colorectal cancer

26
Q

Who are at risk of colorectal cancer?

A 
FAP
HNPCC
IBD
Familial risk 
Previous adenocarcinomas/colorectal cancer
27
Q

What is the inheritance of FAP?

A

Autosomal dominant

28
Q

What happens in FAP?

A

Multiple (>100) adenomas throughout colon
- 50% by 15 y/o
- 95% by 25 y/o
High risk of malignant change in early adulthood, in almost all cases by age 40 years old if untreated

29
Q

What is the genetic change in FAP?

A

APC gene on chromosome 5

30
Q

Screening in have FAP

A

Annual colonoscopy from age 10-12 years

31
Q

If a significant number of polyps is found on screening for FAP, what can be done?

A

Prophylactic protocolectomy

32
Q

What age is a prophylactic protocolectomy usually done in FAP?

A

16-25 years old

33
Q

Extracolonic manifestations of FAP

A 
Benign gastric fundic cystic hyperplastic polyps (benign in stomach)
Duodenal adenomas (approx. 90% in periampullary cancer 5%)
34
Q

What % of FAP gives rise to desmoid tumours?

A

10 - 20%

35
Q

Definition of desmoid tumour

A

Non cancerous growths that occur in the connective tissue

36
Q

What does CHRPE stand for?

A

Congenital retinal hypertrophy of the pigment epithelia

37
Q

Treatment of FAP

A

Prophylactic proctocolectomy

NSAIDs chemoprevention

38
Q

Role of NSAIDs chemoprevention in FAP

A

Sulindac reduces polyp number and prevents recurrence of higher grade adenomas in the retained rectal segment
Reduces the rate at which polyps grow in GIT and rectum

39
Q

Inheritance of HNPCC

A

Autosomal dominant

40
Q

Pathology of HNPCC

A

Tumours have a molecular characteristic called microsatellite instability (MSI) - frequent mutations in short repeated sequences of DNA (microsatellites)

41
Q

Genetics of HNPCC

A

Mutation in DNA mismatch repair (MMR) genes, e.g. MLH1 and MSH2

42
Q

Presentation of HNPCC

A

Early onset colorectal cancer (40s) right sided

43
Q

What side of the colon does HNPCC occur?

A

Mostly right sided

44
Q

Assosiated cancers of HNPCC

A

Endometrial
Genitourinary
Stomach
Pancreas

45
Q

Diagnosis of HNPCC

A

Clinical criteria (Amsterdam/Bethesda) genetic testing

46
Q

Screening in HNPCC

A

From age 25 - 2 yearly colonoscopy

47
Q

Which of FAP and HNPCC has a higher risk?

A

FAP

48
Q

When is there a high moderate risk of a familial history of CRC?

A

CRC in first degree relative kinship, None < 50 y/o

CRC in 2 first degree relatives in kinship, mean < 60 y/o

49
Q

Screening of high moderate risk of familial history of CRC

A

5 yearly colonoscopy from age 50 years

50
Q

When is there a low moderate risk of familial CRC?

A

CRC in 2nd degree relatives
> 60 years
in 1 first degree relative < 50 y/o

51
Q

How often should a patient get a colonoscopy if have had previous CRC?

A

5 yearly

52
Q

How often should familial high risk groups get colonoscopy?

A 
10 years post diagnosis
Then dependent on 
- duration 
- extent 
- activity of inflammation 
- presence of inflammation
53
Q

Treatment of colorectal cancer

A

Surgery
Stoma formation (colostomy)
Chemotherapy
Radiotherapy

54
Q

What would be the palliative care for colorectal cancer?

A

Chemotherapy

Colonic stenting to prevent colonic obstruction

55
Q

What is the staging of colorectal cancer?

A

Dukes staging

56
Q

5 year survival of the different Dukes staging

A 
A = 83% 
B = 64% 
C = 38%
D = 3%
57
Q

What are villous adenomas?

A

Colonic polyps with the potential to become malignant

58
Q

Presentation of villous adenomas

A 
Characteristically secrete large amounts of mucous which can cause electrolyte disturbances
Vast majority asymptomatic
Non specific lower GI symptoms
Secretory diarrhoea may occur
Microcytic anaemia
Hypokalaemia

Gastrointestinal Pathology (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions