Screening Colonoscopy: Is it Screening Colonoscopy: Is it on the Brink of Extinction ?on the Brink of Extinction ?

Patrick R. Pfau, M.D.Patrick R. Pfau, M.D.

Associate ProfessorAssociate Professor

Chief of Clinical GastroenterologyChief of Clinical Gastroenterology

University of Wisconsin School of University of Wisconsin School of Medicine and Public HealthMedicine and Public Health

Learning ObjectivesLearning Objectives

To determine the present state of To determine the present state of colorectal cancer screening with colorectal cancer screening with colonoscopycolonoscopy

To identify the “threats” to screening To identify the “threats” to screening colonoscopycolonoscopy

To determine what will keep colonoscopy To determine what will keep colonoscopy an important colon cancer screening an important colon cancer screening modality modality

305,866,7775305,866,7775

Is screening colonoscopy Is screening colonoscopy going extinct ?going extinct ?

Number of colonoscopies has risen steadily in Number of colonoscopies has risen steadily in U.S. while Flex-Sig and Barium Enemas has U.S. while Flex-Sig and Barium Enemas has dropped significantlydropped significantly– Harewood G, Harewood G, Clin Gastroenterol HepatolClin Gastroenterol Hepatol 2004 2004

Colonoscopy most common endoscopic Colonoscopy most common endoscopic procedure performed in U.S.procedure performed in U.S.– Sonnenberg A, Sonnenberg A, GIE GIE 20082008

Screening colonoscopy has increased greatly in Screening colonoscopy has increased greatly in Medicare populationMedicare population– Fenton JJ, Fenton JJ, Am J Prev MedAm J Prev Med 2008 2008

Increased CRC screening rates primarily result of Increased CRC screening rates primarily result of screening colonoscopyscreening colonoscopy– Phillips K, Phillips K, Med CareMed Care 2007 2007

Why screening colonoscopy is the Why screening colonoscopy is the king ?king ?

Two large cohort studies (Winawer, Two large cohort studies (Winawer, NEJM NEJM 1993 1993 and Citarda and Citarda GutGut 2001) have demonstrated 2001) have demonstrated significant reductions in colon cancer incidence significant reductions in colon cancer incidence if colonoscopy with polypectomy are performedif colonoscopy with polypectomy are performedFOBT and sigmoidoscopy that lead to FOBT and sigmoidoscopy that lead to colonoscopy with polypectomy have been shown colonoscopy with polypectomy have been shown to significantly reduce colorectal cancer mortalityto significantly reduce colorectal cancer mortalityColon cancer incidence decreased 2.6 %/year Colon cancer incidence decreased 2.6 %/year since 1998 with sharp decrease since 2002 since 1998 with sharp decrease since 2002 ((Cancer Cancer 2007)2007)

What are the “threats” to What are the “threats” to screening colonoscopy ?screening colonoscopy ?

iFOBTiFOBT

Fecal DNAFecal DNA

CT ColonographyCT Colonography

Ourselves – how we perform screening Ourselves – how we perform screening colonoscopycolonoscopy

Quantitative immunochemical Quantitative immunochemical FOBT – Threat #1FOBT – Threat #1

Improved detection of hemoglobin as compared to Improved detection of hemoglobin as compared to guaic based FOBT testsguaic based FOBT tests– Immunochemical FOBT testing uses antibodies to human Immunochemical FOBT testing uses antibodies to human

globin expressed in colorectal bleeding. globin expressed in colorectal bleeding.

Colon Cancer Screening with Colon Cancer Screening with iFOBTiFOBT

94 % sensitivity for cancers and 67 % for advanced adenomas with 94 % sensitivity for cancers and 67 % for advanced adenomas with approximate 90% sensitivity in high risk individuals (Levi Z, approximate 90% sensitivity in high risk individuals (Levi Z, Ann Int Ann Int Med Med 20072007))25 – 27 % sensitivity for advanced adenomas but different iFOBT 25 – 27 % sensitivity for advanced adenomas but different iFOBT tests vary (Hundt ,tests vary (Hundt ,Ann Int MedAnn Int Med, 2009), 2009)

90 % - 256 % more sensitive than guaic based FOBT for advanced 90 % - 256 % more sensitive than guaic based FOBT for advanced neoplasia ( Guittet L, neoplasia ( Guittet L, Gut Gut 2007)2007)7 % sensitivity for adenomas < 10 mm (Morikawa T 7 % sensitivity for adenomas < 10 mm (Morikawa T Am J Gastro Am J Gastro 2007)2007)

iFOBT should replace gFOBT in screening for iFOBT should replace gFOBT in screening for patients who will not or cannot have total colon patients who will not or cannot have total colon screening – only helps screening colonoscopyscreening – only helps screening colonoscopy

Fecal DNA Analysis - Threat #2Fecal DNA Analysis - Threat #2

Adenoma and carcinoma cells contain Adenoma and carcinoma cells contain altered DNA that are shed continuouslyaltered DNA that are shed continuouslyMultitarget DNA stool assayMultitarget DNA stool assayRequires entire stool specimen (must be Requires entire stool specimen (must be mailed)mailed)

Fecal DNA and colon cancer Fecal DNA and colon cancer screeningscreening

Ahlquist D, Ahlquist D, GastroenterologyGastroenterology 2000 studied patients with colon cancers, large 2000 studied patients with colon cancers, large adenomas, and normal colonsadenomas, and normal colons– Sensitivity of 91% for colon cancer, 82% for large adenomas and a specificity of Sensitivity of 91% for colon cancer, 82% for large adenomas and a specificity of

93%93%

Imperiale T, Imperiale T, NEJM NEJM 2004 studied patients in a screening population2004 studied patients in a screening population– Poor sensitivity for invasive cancers (52%) and advanced polyps (15%)Poor sensitivity for invasive cancers (52%) and advanced polyps (15%)

Ahlquist D, Ahlquist D, Ann Int Med, 2009, Ann Int Med, 2009, Zou H, Zou H, GastroenterologyGastroenterology 2009 2009– Latest assays approximately 2-3 times more sensitive than earlier assays – detected 46 % - Latest assays approximately 2-3 times more sensitive than earlier assays – detected 46 % -

59% advanced adenomas59% advanced adenomas

Fecal DNA analysis will only lead to more colonoscopies and Fecal DNA analysis will only lead to more colonoscopies and more positive/therapeutic colonoscopiesmore positive/therapeutic colonoscopies

CT Colonography (CTC) – Threat # 3CT Colonography (CTC) – Threat # 3

Joint guideline from the ACS, US Multi-Society Joint guideline from the ACS, US Multi-Society Task Force on CRC, and the ACR (Levin B, Task Force on CRC, and the ACR (Levin B, GastroGastro 2008) 2008)– CTC is comparable to colonoscopy for detection of CTC is comparable to colonoscopy for detection of

polyps of a significant sizepolyps of a significant size– Panel concludes that there are sufficient data to Panel concludes that there are sufficient data to

include CTC as an acceptable option for CRC include CTC as an acceptable option for CRC screening screening

ACRIN study (Johnson C, ACRIN study (Johnson C, NEJMNEJM, 2008), 2008)– CTC should have role in CRC screening for average CTC should have role in CRC screening for average

risk patientsrisk patients

Does CTC screening affect Does CTC screening affect screening with colonoscopy ?screening with colonoscopy ?

(Are our jobs in jeopardy ?)(Are our jobs in jeopardy ?)

Van Dam J, Van Dam J, GastroGastro 2004 2004– CTC would likely have a “significant” impact CTC would likely have a “significant” impact

on the practice of gastroenterology in Americaon the practice of gastroenterology in America

Hur C, Hur C, Clin Gastroenterol HepatolClin Gastroenterol Hepatol 2004 - 2004 -Mathematical ModelMathematical Model– 9-22 % reduction in colonoscopies9-22 % reduction in colonoscopies– Reduction based on referral rate from CTC Reduction based on referral rate from CTC

Schwartz, D , AJG 2007

Schwartz, D , AJG 2007

Schwartz, D , AJG 2007

Schwartz, D , AJG 2007

Schwartz, D , AJG 2007

Impact of CTC on ColonoscopyImpact of CTC on Colonoscopy

Schwartz D, Schwartz D, AJGAJG 2007 2007– A fully operational third party insurer covered A fully operational third party insurer covered

CTC program had no effect on colonoscopies CTC program had no effect on colonoscopies performed, screening colonoscopies performed, screening colonoscopies performed, colonoscopies with polypectomy performed, colonoscopies with polypectomy performed, nor requests for screening performed, nor requests for screening colonoscopy after greater than 3 yearscolonoscopy after greater than 3 years

Bucky and Colon Cancer Bucky and Colon Cancer ScreeningScreening

CRC screening at UW five years after CRC screening at UW five years after initiation of CTC program (2008)initiation of CTC program (2008)

TestTest TotalTotal

ColonoscopyColonoscopy 63.7%63.7%

Barium enemaBarium enema .1%.1%

Flex SigFlex Sig 1.3%1.3%

FOBTFOBT 27.6%27.6%

CT ColonographyCT Colonography 7.2%7.2%

Why has CTC not affected Why has CTC not affected screening colonoscopy ?screening colonoscopy ?

CTC does not replace colonoscopy but CTC does not replace colonoscopy but simply adds an additional test (there are a simply adds an additional test (there are a lot of colons out there)lot of colons out there)CTC has distinct disadvantages compared CTC has distinct disadvantages compared to colonoscopyto colonoscopyIf CTC employs “selective polypectomy” it If CTC employs “selective polypectomy” it will not lead to an additional # of will not lead to an additional # of therapeutic colonoscopiestherapeutic colonoscopies

Extinction of Screening Extinction of Screening Colonoscopy – Ourselves to Colonoscopy – Ourselves to

Blame ? Threat # 4Blame ? Threat # 4Complication Complication (Perforation) rate(Perforation) rate– .016 % (1 in 6000) .016 % (1 in 6000)

Rathgaber S, Rathgaber S, GIEGIE 20062006

– .2 % (1 in 500) Kim D, .2 % (1 in 500) Kim D, NEJMNEJM 2007 2007

– .85 per 1000 .85 per 1000 Rabeneck L, Rabeneck L, Gastro Gastro 20082008

How good are we at detecting How good are we at detecting adenomas ?adenomas ?

Adenoma detection rate (ADR)Adenoma detection rate (ADR)– Barclay R, Barclay R, NEJMNEJM 2006 – ADR ranged from .1 2006 – ADR ranged from .1

to 1.05 at institutionto 1.05 at institution

– Chen Chen AJGAJG 2007 – patients detected with 2007 – patients detected with adenomas ranged from 16-41 % between 9 adenomas ranged from 16-41 % between 9 academic gastroenterologists with ADR academic gastroenterologists with ADR varying from .21 - .86varying from .21 - .86

PhysicianPhysician Cecal Cecal Intub.Intub.%%

Intub.Intub.

time time (min)(min)

W/drawal W/drawal time. time. PolypPolyp

W/drawal W/drawal time. time. No PolypNo Polyp

W/drawal W/drawal timetime

totaltotal

% pts w/ % pts w/ AdemonaAdemona

Adenoma Adenoma Det. RateDet. Rate

11 100100 8.18.1 14.014.0 9.09.0 12.512.5 3737 .82.82

22 100100 6.06.0 13.513.5 8.78.7 10.910.9 3030 .73.73

33 100100 7.97.9 12.712.7 9.69.6 10.710.7 2525 .73.73

44 9898 5.75.7 9.89.8 4.34.3 7.07.0 3030 .67.67

55 9191 9.89.8 10.010.0 7.07.0 8.08.0 1313 .43.43

66 100100 7.07.0 7.27.2 4.54.5 5.65.6 2121 .39.39

77 100100 8.68.6 7.87.8 4.44.4 5.65.6 2020 .26.26

88 100100 8.98.9 5.55.5 3.43.4 4.04.0 2121 .24.24

99 9898 9.89.8 9.89.8 6.26.2 7.47.4 1616 .23.23

1010 9595 9.69.6 8.48.4 5.45.4 6.26.2 77 .09.09

VCVC 55 .11.11

Benson, M Dig Dis Sci, 2009

How can screening colonoscopy How can screening colonoscopy be saved ?be saved ?

Do a better colonoscopyDo a better colonoscopy– TrainingTraining– TimeTime– TechnologyTechnology

Use competing technologies to benefit screening Use competing technologies to benefit screening colonoscopycolonoscopyWork to get more patients screened no matter the Work to get more patients screened no matter the method – everything feeds into colonoscopy eventuallymethod – everything feeds into colonoscopy eventuallyDo not become addicted to screening colonoscopyDo not become addicted to screening colonoscopy

Doing a Better Screening Doing a Better Screening ColonoscopyColonoscopy

TrainingTraining– ASGE and ACGME – 140 colonoscopies during GI ASGE and ACGME – 140 colonoscopies during GI

fellowshipfellowshipChak A GIE 1996 – Trainees do not achieve competence at Chak A GIE 1996 – Trainees do not achieve competence at 100 colonoscopies100 colonoscopiesLee S GIE 2008 – competence in screening colonoscopy Lee S GIE 2008 – competence in screening colonoscopy requires more than 150 casesrequires more than 150 casesSpier B GIE/DDW 2009Spier B GIE/DDW 2009

– No trainee reached independence (>90% cecal intubation) after No trainee reached independence (>90% cecal intubation) after 140 cases140 cases

– First fellow to achieve > 90% cecal intubation took over 300 First fellow to achieve > 90% cecal intubation took over 300 casescases

– Not until 500 colonoscopies were performed that all fellows Not until 500 colonoscopies were performed that all fellows achieved > 90 % cecal intubation rateachieved > 90 % cecal intubation rate

Doing a Better Screening Doing a Better Screening ColonoscopyColonoscopy

TimeTime– Sanchez W, Sanchez W, AJG – AJG – Colonoscopy procedure time correlates with Colonoscopy procedure time correlates with

3 – fold difference in polyp detection3 – fold difference in polyp detection– Barclay R Barclay R NEJMNEJM 2006 – Colonoscopists who had withdrawal 2006 – Colonoscopists who had withdrawal

times > 6 min. found more patients with adenomas (23.8 % vs. times > 6 min. found more patients with adenomas (23.8 % vs. 11.8 %) and advanced adenomas (6.4 % vs. 2.6 %)11.8 %) and advanced adenomas (6.4 % vs. 2.6 %)

– Simmons D Simmons D Aliment Pharmacol TherAliment Pharmacol Ther 2006 – Longer withdrawal 2006 – Longer withdrawal time correlated with more polyps being found – suggested 7 time correlated with more polyps being found – suggested 7 minute withdrawalminute withdrawal

– Barclay R Clin Gastroenterol Hepatol – Implementation of 8 Barclay R Clin Gastroenterol Hepatol – Implementation of 8 minute withdrawal time increased number of adenomas detected minute withdrawal time increased number of adenomas detected (34.7 % vs. 23.5 %)(34.7 % vs. 23.5 %)

– Sawhney M, Sawhney M, GastroGastro 2008 – increasing withdrawal times to 7 2008 – increasing withdrawal times to 7 minutes did not increase adenoma detection rateminutes did not increase adenoma detection rate

PhysicianPhysician Cecal Cecal Intub.Intub.%%

Intub.Intub.

time time (min)(min)

W/drawal W/drawal time. time. PolypPolyp

W/drawal W/drawal time. time. No PolypNo Polyp

W/drawal W/drawal timetime

totaltotal

% pts w/ % pts w/ AdemonaAdemona

Adenoma Adenoma Det. RateDet. Rate

11 100100 8.18.1 14.014.0 9.09.0 12.512.5 3737 .82.82

22 100100 6.06.0 13.513.5 8.78.7 10.910.9 3030 .73.73

33 100100 7.97.9 12.712.7 9.69.6 10.710.7 2525 .73.73

44 9898 5.75.7 9.89.8 4.34.3 7.07.0 3030 .67.67

55 9191 9.89.8 10.010.0 7.07.0 8.08.0 1313 .43.43

66 100100 7.07.0 7.27.2 4.54.5 5.65.6 2121 .39.39

77 100100 8.68.6 7.87.8 4.44.4 5.65.6 2020 .26.26

88 100100 8.98.9 5.55.5 3.43.4 4.04.0 2121 .24.24

99 9898 9.89.8 9.89.8 6.26.2 7.47.4 1616 .23.23

1010 9595 9.69.6 8.48.4 5.45.4 6.26.2 77 .09.09

VCVC 55 .11.11

Benson, M Dig Dis Sci, 2009

Doing a Better Screening Doing a Better Screening ColonoscopyColonoscopy

TechnologyTechnology– ColonoscopesColonoscopes

Self-propelling scopesSelf-propelling scopesRetro scopesRetro scopesCapsule colonoscopyCapsule colonoscopyWide - angleWide - angle

– Auxillary DevicesAuxillary DevicesHoods and capsHoods and capsChromoendoscopyChromoendoscopy

– ImagingImagingNarrow Band ImagingNarrow Band ImagingMagnifying Magnifying AutofluorescenceAutofluorescenceOptical Coherence TomographyOptical Coherence TomographyConfocal MicroscopyConfocal Microscopy

– Added last night – better sedation with propofolAdded last night – better sedation with propofol

Screening Colonoscopy – Is it Screening Colonoscopy – Is it Dying ?Dying ?

External Threats – No real threats at External Threats – No real threats at presentpresent– No test matches colonoscopy for CRC No test matches colonoscopy for CRC

screeningscreening– External threats actually benefit colonoscopyExternal threats actually benefit colonoscopy

Internal Threats – Do a better colonoscopyInternal Threats – Do a better colonoscopy– Know and improve your own personal Know and improve your own personal

complication and adenoma detection rates – complication and adenoma detection rates – each gastroenterologist has to meet a each gastroenterologist has to meet a minimum of standardsminimum of standards