Post on 14-Jan-2016
description
Colonoscopy; Surveillance Indications
SR Brown
Colorectal Surgeon
Sheffield Teaching Hospitals
Colorectal cancer screening in high risk groups
Gut 2002;51(Suppl V)
Screening vs Surveillance
• Screening– Asymptomatic population
• Surveillance– Previous symptoms/high risk
High risk groups
• Previous colorectal cancer
• Acromegaly
• Ureterosigmoidostomy
• Hereditary and Familial bowel cancer
• IBD
• Previous polyps
Aims
• To discuss salient aspects of guidelines
• To highlight recent developments in colonoscopic surveillance
Colorectal cancer surveillance
Colorectal cancer surveillance; aims
• Detect recurrence
• Diagnose and treat metachronous neoplasia
• Evaluate anastomosis
Colorectal cancer surveillance
• ‘Incidence metachronous tumours 5-10%’
• Metachronous cancers – approx. 2%– Cochrane review 1.3% (18/1342)
• Metachronous adenomas– 22% (425/1923)
Colorectal cancer surveillance
• Synchronous/‘early’ metachronous cancers– 4%– 0.6% ‘missed’ due to incomplete colon exam
Familial cancer surveillance
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 35-40 years (whichever later)
If initial clear repeat at age 55
1 FDR<45 yr with CRC
Colonoscopy
At 1st consult or age 35-40 years (whichever later)
If initial clear repeat at age 55
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
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 35-40 years (whichever later)
If initial clear repeat at age 55
1 FDR<45 yr with CRC
Colonoscopy
At 1st consult or age 35-40 years (whichever later)
If initial clear repeat at age 55
Chances of preventing death with screening colonoscopy
35 year old with FDR<45 years
• 1 in 25,000 people aged 30-39 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
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 35-40 years (whichever later)
If initial clear repeat at age 55
1 FDR<45 yr with CRC
Colonoscopy
At 1st consult or age 35-40 years (whichever later)
If initial clear repeat at age 55
Chances of preventing death with screening colonoscopy
55 year old with FDR<45 years
• 1 in 1,630 people aged 50-59 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
Hereditary cancer surveillance
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
Puberty Flexi sig yearly
Colectomy if +ve
IBD surveillance
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
Controversies
• ? Survival advantage (Cochrane review 2004)– No clear evidence – May allow earlier detection of cancer– ?lead-time bias
Controversies
• Ongoing inflammation increases risk
• Dysplasia as a marker for cancer– Reliability– Detection– Histological interpretation
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
Ileo-anal pouch surveillance
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
Surveillance recommendations
• Pouchoscopy
• 1st year then 2-3 yearly
• Increased surveillance (yearly) if– Pre-existing dysplasia/cancer– PSC
• Mucosectomy if high risk
Polyp surveillance
Summary
• Read guidelines!!