1. Colonoscopy; Surveillance Indications
SR Brown
Colorectal Surgeon
Sheffield Teaching Hospitals

2. Colorectal cancer screening in high risk groups
Gut 2002;51(Suppl V)

4. Screening vs Surveillance
Asymptomatic population
Surveillance
Previous symptoms/high risk

5. High risk groups Previous colorectal cancer Acromegaly
Ureterosigmoidostomy
Hereditary and Familial bowel cancer
IBD
Previous polyps

6. Aims To discuss salient aspects of guidelines
To highlight recent developments in colonoscopic surveillance

7. Colorectal cancer surveillance

8. Colorectal cancer surveillance; aims
Detect recurrence
Diagnose and treat metachronous neoplasia
Evaluate anastomosis

9. Colorectal cancer surveillance
‘Incidence metachronous tumours 5-10%’
Metachronous cancers
approx. 2%
Cochrane review 1.3% (18/1342)
Metachronous adenomas
22% (425/1923)

10. Colorectal cancer surveillance
Synchronous/‘early’ metachronous cancers 4%
0.6% ‘missed’ due to incomplete colon exam

11. Familial cancer surveillance

12. Familial Cancer Summary
Family group
Screening procedure
Age at initial screen
Screening procedure and interval
2 FDR with CRC
Colonoscopy
At 1st consult or age years (whichever later)
If initial clear repeat at age 55
1 FDR<45 yr with CRC

13. Lifetime risk of colorectal cancer
Risk Group
Risk (of dying)
General population
1:50
Any family history
1:17
One affected relative <45 years
1:10
Two affected relatives
1:6
Houlston et al. 1970

14. Familial Cancer Summary
Family group
Screening procedure
Age at initial screen
Screening procedure and interval
2 FDR with CRC
Colonoscopy
At 1st consult or age years (whichever later)
If initial clear repeat at age 55
1 FDR<45 yr with CRC

15. Chances of preventing death with screening colonoscopy 35 year old with FDR<45 years
1 in 25,000 people aged develop colorectal cancer per year
Relative risk = 5
Risk of cancer = 1 in 5000 in per year
Assume asymptomatic cancer dwell time of 3 years
Chance of detecting cancer 1 in 1660

16. Familial Cancer Summary
Family group
Screening procedure
Age at initial screen
Screening procedure and interval
2 FDR with CRC
Colonoscopy
At 1st consult or age years (whichever later)
If initial clear repeat at age 55
1 FDR<45 yr with CRC

17. Chances of preventing death with screening colonoscopy 55 year old with FDR<45 years
1 in 1,630 people aged develop colorectal cancer per year
Relative risk = 3
Risk of cancer = 1 in 543 per year
Assume asymptomatic cancer dwell time of 3 years
Chance of detecting cancer 1 in 181

18. Hereditary cancer surveillance

19. Hereditary Cancer Summary
Family group
Screening procedure
Age at initial screen
Screening procedure and interval
FAP
Genetic testing Flexi sig+OGD
Puberty
Flexi sig yearly
Colectomy if +ve
HNPCC
Colonoscopy +/- OGD
25 yrs or 5 yrs before earliest CRC in family
2 yearly colonoscopy and OGD
Juvenile polyposis
Peutz-Jegher
Genetic testing
Colonoscopy + OGD

20. IBD surveillance

21. IBD Summary Disease group Screening procedure Age at initial screen
Screening procedure and interval
UC or Crohn’s coloitis
Colonoscopy+ biopsies every 10cm
After 8 years for pan colitis, 15 years for left sided colitis
3 yrly 2nd decade, 2yrly 3rd decade, yrly thereafter
UC + PSC
Colonoscopy
At diagnosis PSC
Annually

22. Controversies ? Survival advantage (Cochrane review 2004)
No clear evidence
May allow earlier detection of cancer
?lead-time bias

23. Controversies Ongoing inflammation increases risk
Dysplasia as a marker for cancer
Reliability
Detection
Histological interpretation

24. Controversies;detection
Pan-chromoscopy and targeted biopsy (Rutter 2004)
Back-to-back colonoscopy
Conventional then dye-spray
Conventional no dysplasia in 2904 random biopsies
Targeted 157 biopsies 7 patients with dysplasia

25. Ileo-anal pouch surveillance

26. Pouch cancer 15 case reports 10 residual rectal mucosa
5 ??pouch mucosa
All pre-existing dysplasia
8 had cancer in original resection
9 had mucosectomy

27. Surveillance recommendations
Pouchoscopy
1st year then 2-3 yearly
Increased surveillance (yearly) if
Pre-existing dysplasia/cancer
PSC
Mucosectomy if high risk

28. Polyp surveillance

30. Summary
Read guidelines!!