Dr Teresa Chalmers-WatsonChristchurch

14:25 - 14:50 Bowel Cancer Screening- Where Are We Up To?

Colorectal Cancer Screening 2017

Dr Teresa Chalmers-Watson

Consultant Gastroenterologist & Clinical Senior Lecturer

Clinical Advisor – NZ Familial GI Cancer Service

August 2017

Colorectal Cancer Screening

What is the Problem? Do we need Bowel Screening?

What do we do currently?

Risk Stratify

What are the Screening Options for ‘Average Risk’ ?

The Bowel Screening Pilot & Results

Implications for Canterbury & Nationally

Does New Zealand Need Bowel Screening?

Colorectal Cancer:

One of New Zealand’s most Common Cancers

3000 new cases diagnosed each year

Second highest cause of cancer death

1200 die from it

Maori 30% more likely to die

New Zealand has highest incidence rates in world

Bowel Screening detects cancer at earlier stage & saves lives

Age-Standardized Colorectal Cancer Incidence Rates by Sex & World Area.

GLOBOCAN 2008.

Most Common Cancer Deaths in NZ

1656

1252

647 641

463

0

450

900

1350

1800

lung colorectal prostate breast pancreatic

864

659 647

232 215

0

225

450

675

900

1125

Males - most common cancer deathswere from:

lung colorectal prostate melanoma pancreatic

792

633593

248178

0

200

400

600

800

1000

Females - most common cancer deaths were from:

lung breast colorectal pancreatic ovarian

Adenoma to Carcinoma pathway

Normal CancerAdenoma

We can prevent Colorectal Cancer

95% of cancers develop from polyps

The polyp to cancer sequence can take 5-10 years so repeated

opportunities for screening

Remove the polyp before develop Cancer

Reduces incidence of Cancer

We can detect the cancer early -5 year survival by stage of Colorectal Cancer

92%

65%

53%

10%

>95%

What do we do now ?

- depends on ‘level of risk’

What is the Average Risk for individuals in NZ?

55 yrs:

Overall risk 0.6%

75 yrs

Overall risk 5.6%

Men: 1 in 18

Women 1 in 23

What increases your risk of bowel cancer?

Age:

Personal history:

Inflammatory Bowel Disease

Previous Cancer or polyps

Family history:

Other…

Colorectal Cancer Risk: Age is the

strongest risk factor

0.0

100.0

200.0

300.0

400.0

500.0

600.0

'0-

24

25-

29

30-

34

35-

39

40-

44

45-

49

50-

54

55-

59

60-

64

65-

69

70-

74

75-

79

80-

84

85+

Age group

Ag

e s

pecif

ic i

ncid

en

ce p

er

100,0

00

It’s in my genes…

70% of people with bowel cancer will have no family history -

Environmental factors dominant

Genetic factors are significant in 25% of cases

3 to 8% of bowel cancers are a consequence of recognized hereditary

conditions.

Lynch syndrome / HNPCC

Familial Adenomatous Polyposis - FAP

Colorectal Cancer

Am J Med genetics Vol 129C Aug 15th 2004

How do we manage increased familial risk in NZ?

Family history –Category 1 -Slightly Above Average Risk

-one first degree relative with CRC > 55yrs

< 2 fold higher risk - 4% risk at 65yrs, 10% risk at 75yrs

Category 2 –Moderately increased risk

-one first degree relative <55 yrs or 2 FDR’s

- 3-6 fold increased risk -13% risk at 65yrs, 30% risk at 75yrs

Category 3 – Potentially high risk of CRC –-multiple family members, CRC, ovarian, endometrial, urological

- Lynch Syndrome or FAP

New Zealand Guidelines 2004

ObesityObesity – increased risk, abdominal fatness

Physical (in)activity levelsHigh physical activity –lower risk of bowel cancer

DietHigh in fat –particularly animal fat

High meat – especially red, processed

Low fruit / vegetables, ? Ca ? Se ? garlic

Smoking

Alcohol

NSAIDs, Aspirin protective

What else increases my risk of bowel cancer?

What do we do with ‘average’ & ‘slightly

increased risk’ individuals?

Should NZ do Bowel Screening?

The disease must be common & significant

Screening acceptable, safe and cost effective

Screening makes a difference to out come

- Screening reduces mortality from CRC by 16-90%

- Screening reduces incidence of CRC

Significant decline in USA - 2% p.a

- 50 % due to screening

American Cancer Society 2011

Options for Bowel Screening

1. Detect Cancer

Stool tests

Most polyps never bleed

2. Detect Pre-cancerous lesions

CT colon

Colon capsule

Colonoscopy

Flexible Sigmoidoscopy

3. Others…

The Gastroenterologist’s view of

colonoscopy

• Safe

• Well-tolerated

• Sensitive

• Specific

• Safe

• Well Tolerated

• Sensitive

• Specific

The patient’s view of colonoscopy

• Invasive

• Expensive

• Dangerous

• Inconvenient

• Dangerous

• Inconvenient

• Invasive

• Expensive

Detecting Cancer – Stool samples

Faecal immunochemical test (iFOBT)

Detects the globin part of Hb

Requires only one sample

No time off work, discreet, in your own home

Are quantitative so sensitivity can be ‘set’

Less false positives

May detect advanced adenomas

Detecting pre-cancer lesions: Colonoscopy or CTC

CT Colon

Potential advantages

Unsedated

Safe

no perforation with CO2

Good caecal visualization

Stricture fly-through

Extra-intestinal findings

Potential disadvantages

Radiation dose 2-3mSv

Bowel prep required

Only diagnostic

Less good at small polyps

Radiology also stretched

Colonoscopy

The gold standard

Requires bowel prep, day off

Safe but small risks (1/1000)

Diagnostic and therapeutic

If started by age 50 reduce CRC by 90%

Expensive on a population basis

Winawer et al N. Engl J Med 1993; 329:1977-1981

Flexible Sigmoidoscopy

Smaller amount of prep

Smaller amount of risk

Limited visualisation

Smaller benefit

The future?

Bowel Screening Options in NZ

-Modelling

Single sigmoidoscopy is cheapest option and reduce CRC deaths by 16%

FIT followed by colonoscopy most cost effective and reduces CRC deaths by 27%

Internationally – favoured option

This is what the NZ pilot used

Sarafti et al NZMJ 2016

National Bowel Screening Pilot (BSP) in

Waitemata DHB

Four year Pilot – round 1 - 2012 to 2013, round 2 - 2014-2015,

Age range 50-74yrs men & women - approx 136,000 people

People invited every 2 years

Faecal immunochemical test for Haemoglobin (FIT)

Every 2 years

If positive invited for colonoscopy

Two screening rounds complete, 3rd ongoing

Participation in the Pilot by ethnicity?

• Lower for Maori & Pacific, improved with active outreach

• Once participating, variation by ethnicity disappears

56.80%

46.00%

30.40%

53.70%

59.70%

55.20%

50.70%

39.60%

51.60%

57.20%56.20%

52.70%

43.20%

54.30%

57.50%

0%

15%

30%

45%

60%

75%

Total Maori Pacific Asian Other

Rd 1 Rd 2 Rd 3

How many tests are positive?

7.50%

5.90%

5.20%

8.50%

5.40%5.00%

5.50%5.80%

4.70%

0%

2%

5%

7%

9%

Overall Positivity First screen (ageing or moving in) First screen (spoilt or did notrespond to previous invites)

Subsequent screen (successful inone or more previous rounds and

invited again)

Round 1 Round 2 Round 3

7.5% positive test in round 1 – subsequent rounds lower

Bowel screening pilot results (to April 2016 )

Rd 1 Rd 2 Rd3

CRC detection rate DR/1000 screened 2.8

(1-8-9.5)

1.5 1.6

Advanced adenoma DR 15.5 7.7 4.3

Adenoma DR 36.2

(13.3-22.3)

23.7 21.8

PPV Colorectal Ca % 4.3

(4.5-8.6)

3.1 3.8

PPV Advanced adenoma % 24.0 15.8 10.6

PPV adenoma % 56.1

(9.6-40.3)

48.3 53.2

Numbers cancers found (private) 192

(22)

108

(12)

13

(0)

positive predictor value (PPV) is a measure of how many positive results have an outcome of an abnormality or cancer being found. In bowel

screening PPV is the number of cancers found per 100 colonoscopies performed following a positive FIT result.

Did Bowel Screening Pilot find cancers

earlier?

Colorectal Cancer Stage at diagnosis (including polyp cancers)

Rd 1 Rd 2 Rd 3Without

screening *

Stage 1 44.9% 49.5% 72.7% 12%

Stage 2 24.9% 17.9% 9.1% 27%

Stage 3 22.2% 27.4% 9.1% 29%

Stage 4 8.1% 5.3% 9.1% 28%

Stage 1 bowel cancer has > 90% chance of

being successfully treated

Workforce & Resource implications… for CDHB

• There are currently not enough endoscopists to do the work –Gastroenterologists & surgeons

• Waitemata struggled

• Diagnostic work and waiting times affected

• Solutions? Increase trainees, Non specialist endoscopy - limited

• Need ½ a surgeon

• Need ½ a pathologist

• Endoscopy nurses

• GP’s

• Endoscopy physical capacity, administration, clerical

Budget 2016 Announcement

$39.3 million over 4 years for design, planning and set up of National Bowel

Screening Programme

Progressive roll out from mid 2017

Starting with Lower Hutt and Wairarapa

2017-2018 Southern DHB

2018-2019 Canterbury DHB

National Bowel Screening Programme

The Age Range has been raised to 60-74yrs

The threshold for a positive FIT test raised to 200ngHb/ ml buffer

Results from the New Zealand Bowel Screening Pilot

82 % of all cancers in BSP found in those aged 60-74yrs

80% of cancers were found following a FIT result > 200ng Hb/ml

47% positive FIT results were for Hb between 75 & 200ng

Therefore more likelihood of a cancer /advanced adenoma at colonoscopy, reduced colonoscopy requirements and so allows a National Screening Programme to start earlier...

Bowel Screening Programme Configuration

Ministry of Health NBSP

NBSP IT System

(TBC)

National Coordination Centre and Laboratory

Test Kit Provider

Bowel Screening Regional Centres

District Health Boards

Primary Health Organisations

National Quality Improvement

NHI database extract

BSP register

Pre invitation letter

Invitation letter, test kit , consent form

Sample returned to laboratory

Result to register and GP

10 days

GP/Endo nurse refers to

Colonoscopy

42 days

Result letter to participant

Recall to screening in

2 years

Colonoscopy

Recall to screeningin 5 yearsSurveillance

Opt off

Treatment

Opt off

NegativePositive

DHB Population (60-74)

Colonoscopydemand -Round 1 Year 1*

Cancers –Round 1 Year 1*

Colonoscopydemand - Round 1 Year 2*

Cancers -Round 1 Year 2*

Canterbury 82,660 1,212 92 1,254 95

Southern 50,840 744 56 768 58

West Coast 6,250 92 7 95 7

SouthCanterbury

11,670 170 12 175 13

NelsonMarlborough

30,470 447 34 458 35

NBSP - Population, Colonoscopy requirements and Cancers

*These volumes are based on the Bowel Screening Pilot results from

Waitemata

Conclusion - Colorectal Cancer Screening 2017

Colorectal Cancer:

One of New Zealand’s most Common Cancers & 2nd highest cause

of Ca death

New Zealand has highest incidence rates in world

Currently no screening for average risk or slightly increased risk

individuals

Bowel Screening detects cancer at earlier stage & saves lives.

Pilot successful – 300 cancers detected thus far & at earlier stage

National Bowel Screening Programme rolling out …

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