Bowel Cancer

Question 1

Key symptoms and signs that may suggest a diagnosis of bowel cancer include…

Answer 1

Rectal bleeding
Changes in bowel habit
Weight loss
Iron deficiency anaemia

Question 2

What counts as altered bowel habit?

Answer 2

Looser or more frequent bowels for > 6 weeks

Question 3

What is CEA

Answer 3

A tumour marker for monitoring disease progression.

It cannot be relied on for diagnosis inclusion or exclusion.

Question 4

Criteria for direct access colonoscopy - High suspicion of cancer

Answer 4

Palpable or visible rectal mass
Colorectal cancer on imaging
Unexplained rectal bleeding + iron deficiency anaemia
Altered bowel habit and unexplained rectal bleeding in patient ≥50yo

Question 5

Criteria for direct access colonoscopy - routine

Answer 5

Altered bowel habit > 6 weeks in ≥ 50yo
Unexplained PR bleeding ≥ 50yo
Altered bowel habit > 6 weeks duration + unexplained PR bleeding ≥ 40 years
Unexplained iron deficiency anaemia
Polyp > 5 mm on imaging

Other specific criteria if family hx and meeting NZGG category 2 or 3

Question 6

Criteria for direct access colonoscopy - Exclusions (low risk features)

Answer 6

Acute diarrhoea < 6 weeks
PR bleeding < 50yo with no other symptoms
Suspected IBS
Constipation or abdo pain on its own
Low ferritin with normal Hb < 50yo
Colonoscopy within 5 years unless clear indication to repeat
PR bleeding with a visible benign cause

Question 7

When is colonoscopy preferred over CT colonography

Answer 7

If main indication for referral is PR bleeding or a persistent altered bowel habit.

Also preferred if the patient has a Category 2 or 3 family history of bowel cancer

Question 8

When is CT colonography preferred over colonoscopy

Answer 8

Do not have an altered bowel habit or PR bleeding as the predominant indication
Category 1 family history or no family history
> 80 yo +/- significant co-morbidities