Bangkok, Thailand <ul><ul><li>Canal AVIST  Medical Forum </li></ul></ul><ul><ul><li>19 September 2008 </li></ul></ul>Title...
  Bangkok, Thailand Dr Taya Kitiyakara graduated from St Mary’s Hospital, Imperial College, London 1996 after attending Ca...
Colorectal cancer screening, an Asian perspective Dr Taya Kitiyakara  Dept of gastroenterology Faculty of medicine Ramathi...
Content  <ul><li>Incidence </li></ul><ul><li>Investigations/ screening tests </li></ul><ul><li>Implementation/ strategies ...
Incidence
Incidence of colorectal cancer is high <ul><li>Second leading cause of cancer death in the West. </li></ul><ul><li>Estimat...
Incidence of colorectal cancer in Asia Sung et al Lancet 2005
Increasing incidence of colorectal cancer in Asia <ul><li>Increasing incidence of colorectal cancer in Asia </li></ul><ul>...
Increasing mortality from colorectal cancer in Asia <ul><li>Decreasing mortality in western world </li></ul><ul><li>Increa...
Screening is appropriate colorectal cancer <ul><li>Natural history </li></ul><ul><li>Early detection </li></ul><ul><li>Tre...
Evidence for efficacy of screening Author type Initial test/ 2 nd  line n= f/u (mean) % CRC reduction Mandel  1993 RCT FOB...
EFFICACY OF SCREENING- colonoscopy <ul><li>Colonoscopy used in all other screening modalities to remove polyps and confirm...
Asia Pacific consensus recommendations GUT 2008
Investigations and screening tests
Understanding  screening <ul><li>National screening </li></ul><ul><li>Individual screening </li></ul><ul><li>High risk vs....
Tests available for screening <ul><li>Stool tests </li></ul><ul><ul><li>Faecal occult blood (guaiac based) </li></ul></ul>...
Understanding tests <ul><li>Tests for (mainly) early cancer </li></ul><ul><ul><li>Stool tests </li></ul></ul><ul><li>Tests...
Stool tests: FOB tests <ul><li>FOBT sensitivity variable depending on type (high with Hemoccult SENSA) </li></ul><ul><li>H...
FOB in screening studies FOB type N=screened uptake positive +predictive value Hardcastle  et al , lancet 96 Hemoccult n= ...
Immunochemical FOB may be better in Asia <ul><li>Cost-effectiveness: Cost of tests + false positive test  </li></ul><ul><l...
Understanding sensitivity <ul><li>Per Test  sensitivity </li></ul><ul><li>(screening)  programme  sensitivity for test </l...
Imaging-  double contrast barium enema <ul><li>No RCT/ major trials showing reduction in CRC mortality </li></ul><ul><li>I...
CT colonography
Imaging tests- CT colonography <ul><li>CT colonography not in Asia Pacific recommendations. </li></ul><ul><li>Increasing u...
CT colonography- detection rate <ul><li>Sensitivity of CT colonography compared to 2 colonoscopies. </li></ul><ul><li>2 nd...
Endoscopic tests
Flexible sigmoidoscopy <ul><li>Decreasing numbers performed in USA </li></ul><ul><li>‘ incomplete test’ </li></ul><ul><li>...
Colonoscopy- advantages <ul><li>‘ Complete’ test </li></ul><ul><li>10 yr interval </li></ul><ul><li>Expected 90-70% reduct...
Colonoscopy- disadvantages <ul><li>Expensive </li></ul><ul><li>Time and labour intensive </li></ul><ul><li>May be least ac...
Miss rates in back-to-back studies Heresbach et al Endoscopy 2008 Van Rijn et al Am J Gastro 2006 Kaltenbach et al Gut 200...
Quality control requirements for screening <ul><li>Bowel prep </li></ul><ul><li>Training/experience </li></ul><ul><li>Comp...
Implementation  + = ?
FOB may be most cost-effective screening test in Asia <ul><li>Chinese study, Markov model, comparing gFOB, FS, and colonos...
Large variability in compliance in Asia:Population screening studies Saito 2006 Yang et al 2006 Li et al 2003 Weller et al...
Compliance, understanding and barriers to screening <ul><li>Public knowledge of CRC is poor </li></ul><ul><li>Lack of time...
Resource available? <ul><li>400 endoscopy units in Thailand </li></ul><ul><li>(if  FOB Japanese rates from Saito 2006 used...
Targeted/ stratification screening <ul><li>Selective screening for high risk patients? </li></ul><ul><li>Increased risk fo...
Preparation for screening in UK ‘Fitness to scope’ <ul><li>Capacity evaluation </li></ul><ul><li>Audits </li></ul><ul><ul>...
Improvements
New technologies; too new  <ul><li>New endoscopic equipment:  </li></ul><ul><ul><li>High definition/ Digital chromoendosco...
Flat/ depressed lesion detection <ul><li>Recognised in Japan for many years </li></ul><ul><li>Recently accepted in the wes...
Improvement in already available techniques <ul><li>Endoscopic </li></ul><ul><li>Patient education </li></ul><ul><li>Physi...
Endoscopy Units should strive for quality assurance  <ul><li>Audit cycles </li></ul><ul><li>Local rates eg. for cecal intu...
National programmes should adapt to the country <ul><li>Resource </li></ul><ul><li>Geography </li></ul><ul><li>Patient acc...
More research needed <ul><li>Evidence to base national programme and Policies </li></ul><ul><ul><li>Uptake of each screeni...
Summary  <ul><li>Incidence of colorectal cancer in Asia in rising </li></ul><ul><li>Screening reduces mortality from CRC <...
Summary  <ul><li>Education, reduction in barriers, encouragement by physicians needed </li></ul><ul><li>Quality assurance ...
  Bangkok,  Thailand <ul><ul><li>Canal AVIST  Medical Forum </li></ul></ul><ul><ul><li>19 September 2008 </li></ul></ul>En...
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  1. 1. Bangkok, Thailand <ul><ul><li>Canal AVIST Medical Forum </li></ul></ul><ul><ul><li>19 September 2008 </li></ul></ul>Title : Colorectal cancer screening, an Asian perspective Speaker : Dr Taya Kitiyakara Department of Gastroenterology Faculty of Medicine Ramathibodi Hospital, Mahidol University Time : 09:00 (TH)
  2. 2. Bangkok, Thailand Dr Taya Kitiyakara graduated from St Mary’s Hospital, Imperial College, London 1996 after attending Cambridge University for BA in Medical sciences. He was at King’s college Hospital, London for his Senior House Officer (residency) Medical rotation up to 2000. He trained in Gastroenterology in Oxford, 2000-2007, with one year of liver transplantation at the Royal Prince Alfred Hospital, Sydney, Australia in 2004. He has recently started as consultant Gastroenterologist at Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. <ul><ul><li>Canal AVIST Medical Forum </li></ul></ul><ul><ul><li>19 September 2008 </li></ul></ul>
  3. 3. Colorectal cancer screening, an Asian perspective Dr Taya Kitiyakara Dept of gastroenterology Faculty of medicine Ramathibodi hospital Mahidol University
  4. 4. Content <ul><li>Incidence </li></ul><ul><li>Investigations/ screening tests </li></ul><ul><li>Implementation/ strategies </li></ul><ul><li>Improvements </li></ul>
  5. 5. Incidence
  6. 6. Incidence of colorectal cancer is high <ul><li>Second leading cause of cancer death in the West. </li></ul><ul><li>Estimated 49,960 deaths in USA, 2008 </li></ul>Jemal et al Cancer J Clin 2008
  7. 7. Incidence of colorectal cancer in Asia Sung et al Lancet 2005
  8. 8. Increasing incidence of colorectal cancer in Asia <ul><li>Increasing incidence of colorectal cancer in Asia </li></ul><ul><ul><li>‘ Westernisation’ of diet and lifestyle </li></ul></ul><ul><ul><li>Increasing life expectancy </li></ul></ul>H Sriplung et al 2006 J Ferlay et al 2004 KS Chia et al 1995 L Yang et al 2004
  9. 9. Increasing mortality from colorectal cancer in Asia <ul><li>Decreasing mortality in western world </li></ul><ul><li>Increasing mortality in Asia </li></ul>Sung et al Lancet 2005 Mortality rates: men Mortality rates: women
  10. 10. Screening is appropriate colorectal cancer <ul><li>Natural history </li></ul><ul><li>Early detection </li></ul><ul><li>Treatment available and acceptable </li></ul><ul><li>Change in outcome </li></ul>R Rerknimitr et al 2006
  11. 11. Evidence for efficacy of screening Author type Initial test/ 2 nd line n= f/u (mean) % CRC reduction Mandel 1993 RCT FOB/ Colonoscopy 46,551 13 yrs 33% Hardcastle 1996 RCT FOB/ Colonoscopy 152,850 7.8yrs 15% Kronborg 1996 RCT FOB/ Colonoscopy 61,833 10 yrs 18% Winawer et al 1993 Historical controls Colonoscopy 1418 5.9 yrs 90-76%
  12. 12. EFFICACY OF SCREENING- colonoscopy <ul><li>Colonoscopy used in all other screening modalities to remove polyps and confirm CRC </li></ul>Gupta et al 2005
  13. 13. Asia Pacific consensus recommendations GUT 2008
  14. 14. Investigations and screening tests
  15. 15. Understanding screening <ul><li>National screening </li></ul><ul><li>Individual screening </li></ul><ul><li>High risk vs. average risk screening </li></ul><ul><li>asymptomatic </li></ul>
  16. 16. Tests available for screening <ul><li>Stool tests </li></ul><ul><ul><li>Faecal occult blood (guaiac based) </li></ul></ul><ul><ul><li>Faecal occult blood (immunobased) </li></ul></ul><ul><ul><li>Stool DNA testing </li></ul></ul><ul><li>Imaging tests </li></ul><ul><ul><li>Barium tests </li></ul></ul><ul><ul><li>CT colonography </li></ul></ul><ul><li>Endoscopy tests </li></ul><ul><ul><li>Flexible sigmoidoscopy </li></ul></ul><ul><ul><li>Colonoscopy </li></ul></ul>
  17. 17. Understanding tests <ul><li>Tests for (mainly) early cancer </li></ul><ul><ul><li>Stool tests </li></ul></ul><ul><li>Tests for polyps and cancer </li></ul><ul><ul><li>Colonoscopy, </li></ul></ul><ul><ul><li>CT colonography, </li></ul></ul><ul><ul><li>DCBE </li></ul></ul>Joint Guideline , US Multi-society task force on colorectal cancer 2008
  18. 18. Stool tests: FOB tests <ul><li>FOBT sensitivity variable depending on type (high with Hemoccult SENSA) </li></ul><ul><li>Higher sensitivity = lower specificity </li></ul><ul><li>Requires annual/biennial testing </li></ul><ul><li>Further colonoscopy needed if positive </li></ul><ul><li>Acceptable test to initiate screening </li></ul>Detects Collection Cost One-time SENS/SPEC for CRC gFOB pseudoperoxidase complicated cheap (37-79%) / (87-98%) FIT Human globin easier More expensive (65-94%) / (87-97%)
  19. 19. FOB in screening studies FOB type N=screened uptake positive +predictive value Hardcastle et al , lancet 96 Hemoccult n= 152,850 59.6-38% 2.1% 12% CRC 46% neoplasia Kronborg et al Lancet 96 Hemoccult II n=61,833 67% 1.0% 11% CRC 27% adenoma >1cm Mandel et al NEMJ 93 Hemoccult N=46,551 90.2-46% 2.4% 5.6% for CRC Uk 1 st round screen Hema-screen N=478,000 56.8% 1.9% 10.9% cancer 35% adenoma Sung et al Gastroent 03 Hemoccult II N=505 all 20% 8.9% advanced lesions 28.7% neoplasia Sumetchotimaytha et al 2007 Hema-screen n=20,377 all 12.6% 0.8% CRC 3.4% polyps Li et al Chin Med J 2003 FOBT N= 26,827 74% 35.6% 0.2% CRC 0.59% Adenoma
  20. 20. Immunochemical FOB may be better in Asia <ul><li>Cost-effectiveness: Cost of tests + false positive test </li></ul><ul><li>Dietary manipulation is thought difficult in many Asian countries </li></ul>FOB+ FIT+ SENS FOB SENS FIT SPEC FOB SPEC FIT + predict value FOB +predict value FIT Sumetchotimaytha et al 2007 12.6% Hemascreen 12.8% Occultech 0.8% CRC 3.4% polyps 1.1% CRC 8.9% polyps Li et al 2003 35.6% 5.6% 0.2% CRC 0.6% adenomas Not specified (at best 1.3% CRC 3.7% adenomas) Wong et al 2007 41% 14% 100% 89% 70% 94% 16% CRC 42% CRC
  21. 21. Understanding sensitivity <ul><li>Per Test sensitivity </li></ul><ul><li>(screening) programme sensitivity for test </li></ul><ul><ul><li>Repeated chance of detecting lesion </li></ul></ul><ul><ul><li>May be better at detecting rapidly growing cancer compared to an infrequent test </li></ul></ul>Ransohoff Gastroenterology 2005
  22. 22. Imaging- double contrast barium enema <ul><li>No RCT/ major trials showing reduction in CRC mortality </li></ul><ul><li>Interval not determined </li></ul><ul><li>Decreasing use </li></ul><ul><li>Labour intensive </li></ul><ul><li>Training issues </li></ul><ul><li>Radiation </li></ul><ul><li>Superceded by CT colonography </li></ul>
  23. 23. CT colonography
  24. 24. Imaging tests- CT colonography <ul><li>CT colonography not in Asia Pacific recommendations. </li></ul><ul><li>Increasing use/availability </li></ul><ul><li>More acceptable than colonoscopy </li></ul><ul><li>Extra-luminal imaging </li></ul><ul><li>Costly </li></ul><ul><li>Radiation </li></ul><ul><li>Flat/ depressed lesions difficult to image </li></ul><ul><li>Criteria needed for best sensitivity: </li></ul><ul><ul><li>Excellent bowel prep </li></ul></ul><ul><ul><li>Fecal tagging </li></ul></ul><ul><ul><li>Cutting edge equipment </li></ul></ul><ul><ul><li>Analysis of both 2D and 3D images </li></ul></ul><ul><ul><li>Experience of radiologist </li></ul></ul>Castells Gastroenterology 2008
  25. 25. CT colonography- detection rate <ul><li>Sensitivity of CT colonography compared to 2 colonoscopies. </li></ul><ul><li>2 nd colonoscopy aware of all lesions detected from CT and initial colonoscopy </li></ul><ul><li>Minimised known miss rate- true sensitivity of CT results </li></ul>Iannaccone et al 2005 All polyps >6mm Neoplastic >6mm Neoplastic >10mm (n=7) All polyps All neoplastic Second colonoscopy 100% 100% 100% 100% 100% Initial colonoscopy 84% (69-92%) 91% (71-97%) 86% (49-97%) 83% (74-89%) 87% (73-94%) CT colon (3 observers) 86% (72-94%) 81% (60-92%) 100% (70-100%) 63% (53-72%) 64% (48-77%)
  26. 26. Endoscopic tests
  27. 27. Flexible sigmoidoscopy <ul><li>Decreasing numbers performed in USA </li></ul><ul><li>‘ incomplete test’ </li></ul><ul><li>Miss proximal lesions </li></ul><ul><li>False sense of reassurance </li></ul><ul><li>Benefit of cost-effectiveness vs thoroughness may be lost to screenee </li></ul><ul><li>Legal implications? </li></ul><ul><li>Quality of procedure very variable in studies. </li></ul>
  28. 28. Colonoscopy- advantages <ul><li>‘ Complete’ test </li></ul><ul><li>10 yr interval </li></ul><ul><li>Expected 90-70% reduction in CRC mortality </li></ul>
  29. 29. Colonoscopy- disadvantages <ul><li>Expensive </li></ul><ul><li>Time and labour intensive </li></ul><ul><li>May be least acceptable of screening tests </li></ul><ul><li>Recognised complications </li></ul><ul><li>Miss rates and interval cancers </li></ul>Ransohoff Gastroenterology 2005
  30. 30. Miss rates in back-to-back studies Heresbach et al Endoscopy 2008 Van Rijn et al Am J Gastro 2006 Kaltenbach et al Gut 2008 Iannaccone et al Radiology 2005 Year , n= All polyps Adenomas 5-10mm Adenomas >10mm or advanced Systematic review (6 studies) <2004, n=465 21% 13% 2% (0.3-7.3%) Multi-centre study 2001-2005, n=286 28% 9% 11% Double colonoscopy with CT colon 2002-2003, n=88 36% 17% 13% (6-17%) single centre study vs. NBI 2006-2007, n=142 13% 9.5% 0% (0-1.1%)
  31. 31. Quality control requirements for screening <ul><li>Bowel prep </li></ul><ul><li>Training/experience </li></ul><ul><li>Complete insertion rate </li></ul><ul><li>Withdrawal time/technique and polyp detection rate </li></ul><ul><li>Proper consent </li></ul><ul><li>Complete polyp removal </li></ul><ul><li>Timely detection and appropriate management of complications </li></ul><ul><li>Follow-up protocol </li></ul>Joint Guideline , US Multi-society task force on colorectal cancer 2008
  32. 32. Implementation + = ?
  33. 33. FOB may be most cost-effective screening test in Asia <ul><li>Chinese study, Markov model, comparing gFOB, FS, and colonoscopy (population age 50-80yrs) </li></ul><ul><li>Colonoscopy used if initial test positive </li></ul><ul><li>Colonoscopic screening reduced CRC the most (54.1%) </li></ul><ul><li>FOB is most cost-effective (then colonoscopy ,then FS) – US$ 6222 /life year saved </li></ul><ul><li>FOB remains most cost-effective with different compliance to screening, but not if sensitivity is 30-60%, and specificity is 20-50% </li></ul>Tsoi et al APT 2008
  34. 34. Large variability in compliance in Asia:Population screening studies Saito 2006 Yang et al 2006 Li et al 2003 Weller et al 2007 Denis et al 2007 Japan Taiwan China UK 2 ND ROUND France Health care system 1/3 FIT cost paid by screenee Combined screening of 5 cancers Pay system not specified NHS state funded State funded N= 35,602,782 26,008 26,827 127,746 182,274 Test FIT FIT FOB/FIT FOB FOB Uptake 17% 82% 74% 52.1% 55.4% Positive test (of returned tests) 7% 5.6% 35.6/5.6% 1.77% 3.4% %follow up colonoscopy 58% 68% 7.1% 82.8% 87.9% % with CRC of participants 0.16% 0.19% 0.07% 0.094% 0.23%
  35. 35. Compliance, understanding and barriers to screening <ul><li>Public knowledge of CRC is poor </li></ul><ul><li>Lack of time, financial constraints </li></ul><ul><li>Lack of physician’s recommendation </li></ul><ul><li>Lower knowledge about cancer and screening tests less likely to screen </li></ul><ul><li>Tests – embarrassing </li></ul><ul><li>No health insurance </li></ul><ul><li>‘ Ostrich’ strategy </li></ul><ul><li>Popular support from press and public figures </li></ul>Sung et al 2008 Ransohoff et al 2005
  36. 36. Resource available? <ul><li>400 endoscopy units in Thailand </li></ul><ul><li>(if FOB Japanese rates from Saito 2006 used ) </li></ul><ul><li>=126,405 colonoscopies needed </li></ul><ul><li>= 316 additional colonoscopies/ unit </li></ul><ul><li>Not counting further surveillance colonoscopies needed </li></ul>National database 2007 Department of Provincial Administration Ministry of Interior Thailand Men aged 50-70yrs 4,993,425 Women aged 50-70yr 5,628,906 Total 10,622,331 Total aged 49yrs 821,922
  37. 37. Targeted/ stratification screening <ul><li>Selective screening for high risk patients? </li></ul><ul><li>Increased risk for those with FH of CRC </li></ul><ul><li>‘ Relaxed’ FH screening guideline may be of benefit </li></ul><ul><li>RISK SCORING for deciding initial test </li></ul><ul><ul><li>Using age/ sex/ FH or distal findings </li></ul></ul><ul><ul><li>Reducing number of colonoscopy required by 40% </li></ul></ul><ul><ul><li>Detecting 89-92% of CRCs </li></ul></ul>Johns et al Am J Gastro 2001 Lin et al Gastroenterology 2006 Imperiale et al Ann Intern Med 2003 Subramanian et al Colorectal Dis 2008
  38. 38. Preparation for screening in UK ‘Fitness to scope’ <ul><li>Capacity evaluation </li></ul><ul><li>Audits </li></ul><ul><ul><li>Complete caecal intubation rate (national) </li></ul></ul><ul><ul><li>Improving endoscopy list efficiency </li></ul></ul><ul><li>Global rating score </li></ul><ul><li>‘ Driving’ test </li></ul><ul><li>National endoscopy training centres </li></ul><ul><li>JAG accreditation </li></ul><ul><li>Funding incentives </li></ul>Nnoaham et al Gut 2008 Pickard et al Colorectal dis 2006 Bowles et al Gut 2004 Ball et al BMJ 2004 www.grs.nhs.uk
  39. 39. Improvements
  40. 40. New technologies; too new <ul><li>New endoscopic equipment: </li></ul><ul><ul><li>High definition/ Digital chromoendoscopy eg. NBI (Olympus), i-scan (Pentax) </li></ul></ul><ul><ul><li>confocal microendoscopy </li></ul></ul><ul><li>Capsule endoscopy (colonic setting) </li></ul><ul><li>Fecal DNA </li></ul>
  41. 41. Flat/ depressed lesion detection <ul><li>Recognised in Japan for many years </li></ul><ul><li>Recently accepted in the west </li></ul><ul><li>Difficult to detect </li></ul><ul><li>Higher proportion of high-grade dysplasia/ carcinoma </li></ul><ul><li>May be one factor for interval cancers </li></ul>Muto et al Dis Colon Rectum 1985 Kudo et al World J Surg 2000 Soetikno et al JAMA 2008 Rembacken et al Lancet 2000
  42. 42. Improvement in already available techniques <ul><li>Endoscopic </li></ul><ul><li>Patient education </li></ul><ul><li>Physician education- referral/ follow-up </li></ul><ul><li>General satisfaction </li></ul>East et al APT 2008 Sung et al Am J Gastro 2008 Turner et al J Gen Intern Med 2003
  43. 43. Endoscopy Units should strive for quality assurance <ul><li>Audit cycles </li></ul><ul><li>Local rates eg. for cecal intubation, polyp detection, interval cancers, complications </li></ul><ul><li>Appropriate indication and intervals for procedures according to guidelines (improving cost-effectiveness) </li></ul><ul><li>Training in detecting flat polyps </li></ul><ul><li>Consenting </li></ul><ul><li>Training trainers/trainees </li></ul>
  44. 44. National programmes should adapt to the country <ul><li>Resource </li></ul><ul><li>Geography </li></ul><ul><li>Patient acceptance/education </li></ul><ul><li>Healthcare system and infrastructure </li></ul><ul><li>Funding of screening </li></ul>
  45. 45. More research needed <ul><li>Evidence to base national programme and Policies </li></ul><ul><ul><li>Uptake of each screening modality? </li></ul></ul><ul><ul><li>Barriers to screening in each country? </li></ul></ul><ul><ul><li>Dietary restrictions for FOB possible? </li></ul></ul><ul><ul><li>Possibility of mixed strategies or targeted screening? </li></ul></ul><ul><ul><li>Pilot studies. </li></ul></ul><ul><ul><li>Increase in number of colonoscopist/ pathologist/ surgeons needed? </li></ul></ul>
  46. 46. Summary <ul><li>Incidence of colorectal cancer in Asia in rising </li></ul><ul><li>Screening reduces mortality from CRC </li></ul><ul><li>Screening tests available include FOB, CT colonography, colonoscopy </li></ul><ul><li>Per-test sensitivity vs per- programme sensitivity (which require infrastructure to ensure repeat testing) </li></ul>
  47. 47. Summary <ul><li>Education, reduction in barriers, encouragement by physicians needed </li></ul><ul><li>Quality assurance is needed for colonoscopy and CT colonography </li></ul><ul><li>Resource may be a limitation </li></ul><ul><li>Stratification or mixed strategies may be more cost-effective </li></ul><ul><li>Pilot studies in screening general population likely to be needed- up-take/ capacity/ cost-effectiveness for each country </li></ul>
  48. 48. Bangkok, Thailand <ul><ul><li>Canal AVIST Medical Forum </li></ul></ul><ul><ul><li>19 September 2008 </li></ul></ul>End of Presentation by Dr Taya Kitiyakara

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