Colonoscopy – Ready Colonoscopy – Ready to be Replaced as a to be Replaced as a

Screening Tool?Screening Tool?

Vivien WongVivien Wong

North District HospitalNorth District Hospital

January 16January 16thth, 2010, 2010

Joint Hospital Surgical Grand Round

Colorectal CancerColorectal Cancer High incidence among both male and High incidence among both male and

female in Hong Kongfemale in Hong Kong– 22ndnd most commonly diagnosed cancer most commonly diagnosed cancer

4000 cases per year4000 cases per year– 22ndnd most common cause for cancer death most common cause for cancer death

1700 cases per year1700 cases per yearHong Kong Cancer Registry 2007Hong Kong Cancer Registry 2007

Well-established treatmentWell-established treatment Known possible malignant transformation Known possible malignant transformation

of benign adenomatous polypsof benign adenomatous polyps– Removal of benign polyps can prevent Removal of benign polyps can prevent

development into invasive carcinomadevelopment into invasive carcinoma

ColonoscopyColonoscopy

Investigation of Investigation of choicechoice

InvasiveInvasive Risk of perforationRisk of perforation DiscomfortDiscomfort Sedation/GASedation/GA

Any non-invasive method to replace Any non-invasive method to replace colonoscopy for screening?colonoscopy for screening?

Barium enemaBarium enema

The conventional alternative in The conventional alternative in patients not suitable or unwilling to patients not suitable or unwilling to perform colonoscopyperform colonoscopy

Efficacy significantly lower compared Efficacy significantly lower compared to colonoscopyto colonoscopy

Sosna et al. Critical Analysis of the Performance of Double-Contrast Barium Enema for Detecting Colorectal Polyps 6 mm

in the Era of CT Colonography. Am J Roentgenol, Feb 2008; 190: 374 - 385.

Polyps ≥ Polyps ≥ 10mm10mm

Polyps 6-9 mmPolyps 6-9 mm

SensitivitySensitivity 70%70% 45%45%

SpecificitySpecificity 85%85%

New technologyNew technology

CT ColonographyCT ColonographyCapsule endoscopyCapsule endoscopy

CT ColonographyCT Colonography

CT Colonography (CTC)CT Colonography (CTC)

Introduced since mid-1990sIntroduced since mid-1990s

Uses computed tomography to Uses computed tomography to perform an imaging evaluation of the perform an imaging evaluation of the coloncolon

Requires distension of large bowel Requires distension of large bowel for viewing of intraluminal lesionsfor viewing of intraluminal lesions

a.k.a. “Virtual Colonoscopy”a.k.a. “Virtual Colonoscopy”

Recent screening guidelinesRecent screening guidelines– The ACS guideline 2010The ACS guideline 2010

CTC is listed as one of the option of CRC CTC is listed as one of the option of CRC screening in average-risk population over screening in average-risk population over age of 50age of 50

– The ACG guideline 2009The ACG guideline 2009 CTC every 5 years replaced barium enema CTC every 5 years replaced barium enema

as the alternative colorectal cancer as the alternative colorectal cancer prevention testprevention test

Advantages:Advantages: Non-invasiveNon-invasive Assessment of extra-colonic pathologyAssessment of extra-colonic pathology

Concerns:Concerns: Sensitivity and SpecificitySensitivity and Specificity Safety issueSafety issue

– Bowel preparationBowel preparation– Colonic distentionColonic distention– RadiationRadiation

Sensitivity and SpecificitySensitivity and Specificity

Initial small trials involved polyp-rich Initial small trials involved polyp-rich cohorts and focused largely on cohorts and focused largely on technique developmenttechnique development

Subsequent larger trials 2003-2005Subsequent larger trials 2003-2005

No. of No. of patientspatients

Polyps ≥ 6mmPolyps ≥ 6mm

SensitivitySensitivity SpecificitySpecificity

Cotton Cotton et al et al 20042004 600600 39%39% 90.5%90.5%

Rockey Rockey et al et al 614614 51%51% ----

Johnson Johnson et al et al 703703 57%57% 95%95%

New techniques developedNew techniques developed– Stool taggingStool tagging– 3D-reconstruction views3D-reconstruction views– Multidetector row CT scannersMultidetector row CT scanners

No. of No. of PatientPatient

ss

Polyps Polyps ≥ 6mm≥ 6mm

Adenoma Adenoma ≥ 10mm≥ 10mm

SensitivitSensitivityy

SpecificiSpecificityty

SensitiviSensitivityty

SpecificiSpecificityty

Pickardt Pickardt et alet al 12331233 89%89% 94%94% 89%89%Stool taggingStool tagging3D polyp detection3D polyp detection

ACRIN 6664ACRIN 6664

>2500>2500in 15 in 15

centercenterss

---- 90%90% 86%86%

Stool taggingStool taggingAutomated CO2 deliveryAutomated CO2 delivery≥≥16 slice multidetector 16 slice multidetector row CTrow CT2D and 3D polyp detection2D and 3D polyp detection

MunichMunich 300300 ---- 92%92%64 slice multidetector CT64 slice multidetector CT3D polyp detection3D polyp detection

Mayo ClinicMayo Clinic 452452 ---- 95%95% 3D polyp detection3D polyp detection

Regge Regge et alet al

937937in 20 in 20

centercenterss

85%85% 88%88% ---- ----

The Recommended The Recommended SpecificationsSpecifications

Bowel preparationBowel preparation PEG or phosphosodaPEG or phosphosoda

Stool & fluid taggingStool & fluid tagging Not mandatory but recommended and Not mandatory but recommended and validatedvalidated

Bowel distensionBowel distension Scanning in two positionsScanning in two positions Automatic insufflation recommendedAutomatic insufflation recommended

Acquisition Acquisition parameters & parameters & radiation doseradiation dose

Multidetector CT ≥ 4 sliceMultidetector CT ≥ 4 slice Slice thickness ≤ 3mmSlice thickness ≤ 3mm Reconstruction level ≤ 2mmReconstruction level ≤ 2mm Low radiation dose, ≤ 50% of the diagnostic Low radiation dose, ≤ 50% of the diagnostic reference level for routine abdominopelvic CTreference level for routine abdominopelvic CT

Data interpretationData interpretation To ensure adequate bowel distension: 2D viewTo ensure adequate bowel distension: 2D view Polyp detection: Primary 2D or 3D searchPolyp detection: Primary 2D or 3D search Polyp characterization: 2D multiplanar or 3D Polyp characterization: 2D multiplanar or 3D images, data from both positions, and multiple images, data from both positions, and multiple window settingswindow settingsMcFarland et al. ACR Colon Cancer Committee White Paper: Status of

CT Colonography 2009. J Am Coll Radiology 2009;6:756-772

Capsule EndoscopyCapsule Endoscopyof the Colonof the Colon

Capsule endoscopy of the Capsule endoscopy of the coloncolon

Cleared for marketing in European Cleared for marketing in European Union since 2006Union since 2006

Uses an ingestibleUses an ingestiblecapsule with camerascapsule with camerasto acquire videoto acquire videoimages of the colonicimages of the colonicmucosa as it goesmucosa as it goesthrough the bowelthrough the bowel

PillCam Colon (Given Imaging, Yoqneam, Israel)PillCam Colon (Given Imaging, Yoqneam, Israel)

Capsule endoscopy of the Capsule endoscopy of the coloncolon

Cleared for marketing in European Cleared for marketing in European Union since 2006Union since 2006

Uses an ingestibleUses an ingestiblecapsule with camerascapsule with camerasto acquire videoto acquire videoimages of the colonicimages of the colonicmucosa as it goesmucosa as it goesthrough the bowelthrough the bowel

PillCam Colon (Given Imaging, Yoqneam, Israel)PillCam Colon (Given Imaging, Yoqneam, Israel)

•31mm x 11mm•Two cameras at each end covering 156°•Acquires pictures at rate of 4 fps

Esophagus& Stomach

SmallIntestine

Terminal ileum& ColonSleep

modeReactivationafter 2 hours

Bowel preparationBowel preparation– Polyethylene glycol solutionPolyethylene glycol solution– Sodium phosphateSodium phosphate– DomperidoneDomperidone– Bisacodyl rectal suppositoryBisacodyl rectal suppository

Data recordingData recording– Data transmitted from capsule to a data Data transmitted from capsule to a data

recorder connected to the patient during the recorder connected to the patient during the procedureprocedure

AnalysisAnalysis– Given Imaging RAPID workstationGiven Imaging RAPID workstation

Non-invasiveNon-invasive Less discomfortLess discomfort Sedation-freeSedation-free Away from doctor’s officeAway from doctor’s office

– Less disruption to patient’s routineLess disruption to patient’s routine

How well does it do?How well does it do?

Pubmed and MEDLINE search:Pubmed and MEDLINE search:– ““Pillcam colon”, “capsule colon Pillcam colon”, “capsule colon

endoscopy”endoscopy”

Six prospective trialsSix prospective trials One cost-effectiveness studyOne cost-effectiveness study One safety study with pacemakersOne safety study with pacemakers Case reportsCase reports

Venue of Venue of studystudy

Patients Patients recruited recruited (analyzed(analyzed

))

Age of Age of patientpatient

s s (mean)(mean)

Any polypsAny polyps Polyp ≥ 6mmPolyp ≥ 6mm

SensitiviSensitivity (95% ty (95%

CI)CI)

SpecificitSpecificityy

(95% CI)(95% CI)

SensitiviSensitivity (95% ty (95%

CI)CI)

SpecificitSpecificityy

(95% CI) (95% CI)

EliakimEliakim et al 2006 et al 2006 IsraelIsrael 9191(84)(84)

26-75 26-75 (57)(57)

56%56%(39-72)(39-72)

69%69%(56-82)(56-82)

50%50%(26-75)(26-75)

83%83%(73-91)(73-91)

Schoofs Schoofs et al et al 20062006 BelgiumBelgium 4141

(36)(36)26-75 26-75 (56)(56) 76%76% 64%64% 60%60% 73%73%

Gay Gay et al 2009et al 2009 FranceFrance 128128(126)(126)

n/an/a(55)(55) 76%76% 76%76% 69%69% n/an/a

Sieg Sieg et al 2009et al 2009 GermanGermanyy

3838(36)(36)

23-73 23-73 (56)(56) 55%55% 96%96% n/an/a n/an/a

Gossum Gossum et al et al 20092009

8 8 EuropeaEuropea

n n centrescentres

332332(320)(320)

22-84 22-84 (58)(58)

72%72%(68-75)(68-75)

78%78%(71-84)(71-84)

64%64%(59-72)(59-72)

84%84%(81-87)(81-87)

Comparative Studies:Comparative Studies:Pillcam Colon vs ColonoscopyPillcam Colon vs Colonoscopy

Venue of Venue of studystudy

Patients Patients recruited recruited (analyzed(analyzed

))

Age of Age of patientpatient

s s (mean)(mean)

Any polypsAny polyps Polyp ≥ 6mmPolyp ≥ 6mm

SensitiviSensitivity (95% ty (95%

CI)CI)

SpecificitSpecificityy

(95% CI)(95% CI)

SensitiviSensitivity (95% ty (95%

CI)CI)

SpecificitSpecificityy

(95% CI) (95% CI)

EliakimEliakim et al 2006 et al 2006 IsraelIsrael 9191(84)(84)

26-75 26-75 (57)(57)

56%56%(39-72)(39-72)

69%69%(56-82)(56-82)

50%50%(26-75)(26-75)

83%83%(73-91)(73-91)

Schoofs Schoofs et al et al 20062006 BelgiumBelgium 4141

(36)(36)26-75 26-75 (56)(56) 76%76% 64%64% 60%60% 73%73%

Gay Gay et al 2009et al 2009 FranceFrance 128128(126)(126)

n/an/a(55)(55) 76%76% 76%76% 69%69% n/an/a

Sieg Sieg et al 2009et al 2009 GermanGermanyy

3838(36)(36)

23-73 23-73 (56)(56) 55%55% 96%96% n/an/a n/an/a

Gossum Gossum et al et al 20092009

8 8 EuropeaEuropea

n n centrescentres

332332(320)(320)

22-84 22-84 (58)(58)

72%72%(68-75)(68-75)

78%78%(71-84)(71-84)

64%64%(59-72)(59-72)

84%84%(81-87)(81-87)

Comparative Studies vs Comparative Studies vs ColonoscopyColonoscopy

11.6mm x 31.5mm11.6mm x 31.5mm Increased angle of Increased angle of

view to 172°view to 172°

Adjusts frame rate Adjusts frame rate automaticallyautomatically– 35 fps while in 35 fps while in

motionmotion– 4 fps while 4 fps while

stationarystationary

Measuring tool in Measuring tool in the analysis the analysis software for polyp software for polyp sizesize

Venue of studyVenue of study 5 Israeli centres5 Israeli centres

Patients recruitedPatients recruited 104104

Patients analyzedPatients analyzed 9898

Age of patients (mean)Age of patients (mean) 18-57 (50)18-57 (50)

Polyps ≥ 6mmPolyps ≥ 6mm

SensitivitySensitivity 8989

SpecificitySpecificity 7676

Polyps ≥ 10mmPolyps ≥ 10mm

SensitivitySensitivity 8888

SpecificitySpecificity 8989Eliakim et al. Prospective mulitcenter performance evaluation of the second-generation colon capsule

compared with colonoscopy. Endoscopy 2009;41:1026-1031.

Comparative Study:Comparative Study:Pillcam Colon Pillcam Colon 22 vs Colonoscopy vs Colonoscopy

SafetySafety– No complication from the capsule in all No complication from the capsule in all

the six prospective trialsthe six prospective trials– Incompliance mainly due to anxiety (and Incompliance mainly due to anxiety (and

hence inability to swallow the capsule)hence inability to swallow the capsule)– Capsules were proven safe to use in Capsules were proven safe to use in

patients with implantable cardioverter-patients with implantable cardioverter-defibrillatorsdefibrillators Bandorski et al. Do endoscopy capsules interfere with

implantable cardioverter-defibrillators? Endoscopy 2009;41:457-461

ConclusionConclusion Colorectal cancer is a significant disease Colorectal cancer is a significant disease

suitable for population screeningsuitable for population screening Colonoscopy is the screening tool of Colonoscopy is the screening tool of

choice at the moment in suitable patientschoice at the moment in suitable patients Non-invasive screening tool is under Non-invasive screening tool is under

development in hope to replace the development in hope to replace the invasive colonoscopyinvasive colonoscopy

CT colonography is now accepted as a CT colonography is now accepted as a primary screening tool in the average-risk primary screening tool in the average-risk population in Americapopulation in America

Efficacy of colon capsule endoscopy is yet Efficacy of colon capsule endoscopy is yet to be provento be proven

In our locality…?In our locality…?

HospitalHospital ColonoscopyColonoscopy CTCCTC CapsuleCapsule

AA $14820-$27840$14820-$27840 $5800$5800 $17000-$17000-$20000$20000

BB $7300$7300 $5000-$7600$5000-$7600 n/an/a

CC n/an/a $4500$4500 n/an/a

No official colorectal cancer screening No official colorectal cancer screening programme launched yetprogramme launched yet

Which method to adopt as the primary Which method to adopt as the primary investigation to achieve best efficacy is investigation to achieve best efficacy is still yet to be definedstill yet to be defined

Thank youThank you