Your SlideShare is downloading. ×
Screening  for   colorectal  cancer Lars  Påhlman Dept  Surgery,  Colorectal  unit University  Hospital,  Uppsala, Sweden
What  is screening
‘ The  presumptive  identification  of  unrecognised  disease  or  defect  by  application  of  tests,  examinations  or  ...
Ideal  screening  situation <ul><li>Cut - off  value </li></ul><ul><li>No  disease Disease </li></ul><ul><li>  -  test   +...
The  common  screening  situation <ul><li>Cut - off  value </li></ul><ul><li>  No  disease  Disease </li></ul><ul><li>  - ...
Colorectal  cancer  -  Screening <ul><li>Screening  is  not  a  diagnostic  test. </li></ul><ul><li>A  positive  test  mus...
Colorectal  cancer  -  Screening <ul><li>The  disease  must  be  difficult  to  treat  once  it  is  symptomatic. </li></u...
Colorectal  cancer  -  Screening <ul><li>High  sensitivity ! </li></ul><ul><li>A   negative  predictive  value   is  impor...
Colorectal  cancer  -  Screening <ul><li>Screening  does  not  reduce  the  incidence. </li></ul><ul><li>Data  on  surviva...
A B Detectable by  screening Clinically detectable Length  biased  sampling Time
Length  time  bias <ul><li>  X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><...
Time A B C D The  disease starts Detectable Clinically presented Death Lead  time Lead  time  bias
Lead  time  bias <ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><...
Prevention Cure Early diagnosis
Colorectal  cancer  <ul><li>Prevention </li></ul><ul><li>Changing  life  style  ? </li></ul><ul><li>No </li></ul>
Colorectal  cancer <ul><li>Chemo - prevention ? </li></ul><ul><li>ASA </li></ul><ul><li>Sulindac </li></ul><ul><li>COX - 2...
Colorectal  cancer  <ul><li>Cure </li></ul><ul><li>More  effective  treatment  ? </li></ul><ul><li>Yes </li></ul>
 
Colorectal  cancer  <ul><li>Early  diagnosis </li></ul><ul><li>Screening  ? </li></ul><ul><li>Yes </li></ul>
Colorectal  cancer  -  Screening <ul><li>Identify  risk  groups </li></ul><ul><li>Inflammatory  bowel  disease </li></ul><...
Colorectal  cancer  -  Screening <ul><li>Inflammatory  bowel  disease </li></ul><ul><li>Pancolitis  and  low  age  at  dia...
Colorectal  cancer  -  Screening <ul><li>Familiar  polyposis  coli </li></ul><ul><li>All  known  families  in  register </...
Colorectal  cancer  -  Screening <ul><li>Cancer  family  syndrome  HNPCC </li></ul><ul><li>A  rare  condition ? </li></ul>...
Colorectal  cancer  -  Screening <ul><li>Known  colorectal  cancer </li></ul><ul><li>A  ‘clean’  colon  perioperatively </...
Colorectal  cancer  -  Screening <ul><li>Known  adenomas </li></ul><ul><li>‘ Clean’  the  colon  once </li></ul><ul><li>‘ ...
Colorectal  cancer  -  Screening <ul><li>Known  adenomas </li></ul><ul><li>‘ High - risk’  group </li></ul><ul><li>>  3  a...
Colorectal  cancer  -  Screening <ul><li>Known  adenomas </li></ul><ul><li>‘ Low - risk’  group </li></ul><ul><li><  3  ad...
Screening  för  kolorektal  cancer <ul><li>FOBT </li></ul><ul><li>Tumörmarkörer  i  feaces </li></ul><ul><li>Skopier </li>...
Screening  för  kolorektal  cancer <ul><li>EU  rekommenderar   screening </li></ul><ul><li>Riktlinjerna  FoU </li></ul><ul...
Colorectal  cancer  -  Screening <ul><li>Faecal  occult  blood  testing </li></ul><ul><li>Low  sensitivity </li></ul><ul><...
Colorectal  cancer  -  Screening <ul><li>Faecal  occult  blood  testing </li></ul><ul><li>Minnesota - trial USA </li></ul>...
FOBT  Screening - mortality  from  CRC Heitson et an. Cochrane Database of Systematic Reviews  2007
FOBT  screening -  total  mortality Heitson et an. Cochrane Database of Systematic Reviews  2007
Colorectal  cancer  -  Screening <ul><li>Faecal  occult  blood  testing </li></ul><ul><li>What  do  we  know  from  these ...
Colorectal  cancer  -  Screening <ul><li>Flexible  sigmoidoscopy </li></ul><ul><li>Case-control  studies </li></ul><ul><li...
Colorectal  cancer  -  Screening <ul><li>Flexible  sigmoidoscopy </li></ul><ul><li>Rationale </li></ul><ul><li>Single  sig...
Colorectal  cancer  -  Screening <ul><li>Flexible  sigmoidoscopy </li></ul><ul><li>Rationale </li></ul><ul><li>Cancers  st...
Colorectal  cancer  -  Screening <ul><li>Flexible  sigmoidoscopy </li></ul><ul><li>Rationale </li></ul><ul><li>Identify  t...
Flex-sig  screening - CRC  mortality Atkin et al, Lancet 2010
Colorectal  cancer  -  Screening <ul><li>Colonoscopy  once ? </li></ul><ul><li>Why  not ! </li></ul>
Colorectal  cancer  -  Screening <ul><li>Colonoscopy  once </li></ul><ul><li>Incidence Adenomas </li></ul><ul><li>Cancers ...
Colorectal  cancer  -  Screening <ul><li>NordICC </li></ul><ul><li>Norway,  Sweden </li></ul><ul><li>Poland,  Holland </li...
Colorectal  cancer  -  Screening <ul><li>FOB - testing </li></ul><ul><li>the  only  evidence </li></ul><ul><li>based  tech...
Colorectal  cancer  -  Screening <ul><li>How  to </li></ul><ul><li>Implement </li></ul><ul><li>FOBT – testing ? </li></ul>
Colorectal  cancer  -  Screening <ul><li>How  to  continue </li></ul><ul><li>Implement  it  slowly </li></ul><ul><li>Check...
 
Colorectal  cancer  -  Screening <ul><li>Stop  the  experiment </li></ul><ul><li>if  the  endpoints </li></ul><ul><li>are ...
Colorectal  cancer  -  Screening <ul><li>Do  we  know  the  endpoints ? </li></ul><ul><li>We  can  use  surrogate  endpoin...
Colorectal  cancer  -  Screening <ul><li>Surrogate  endpoints </li></ul><ul><li>Compliance     60 % </li></ul><ul><li>  P...
Upcoming SlideShare
Loading in...5
×

MCC 2011 - Slide 18

1,215

Published on

0 Comments
1 Like
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
1,215
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
1
Comments
0
Likes
1
Embeds 0
No embeds

No notes for slide

Transcript of "MCC 2011 - Slide 18"

  1. 1. Screening for colorectal cancer Lars Påhlman Dept Surgery, Colorectal unit University Hospital, Uppsala, Sweden
  2. 2. What is screening
  3. 3. ‘ The presumptive identification of unrecognised disease or defect by application of tests, examinations or other procedures that can be applied rapidly’ U.S. Commission on Chronic Illness
  4. 4. Ideal screening situation <ul><li>Cut - off value </li></ul><ul><li>No disease Disease </li></ul><ul><li> - test + test </li></ul>
  5. 5. The common screening situation <ul><li>Cut - off value </li></ul><ul><li> No disease Disease </li></ul><ul><li> - test + test </li></ul>
  6. 6. Colorectal cancer - Screening <ul><li>Screening is not a diagnostic test. </li></ul><ul><li>A positive test must in most situations be followed by another test. </li></ul>
  7. 7. Colorectal cancer - Screening <ul><li>The disease must be difficult to treat once it is symptomatic. </li></ul><ul><li>There must be advantages with early detection. </li></ul><ul><li>The test must detect pre -clinical lesions </li></ul>
  8. 8. Colorectal cancer - Screening <ul><li>High sensitivity ! </li></ul><ul><li>A negative predictive value is important, i.e., to give a correct answer when the test is negative. </li></ul><ul><li>High specificity ! </li></ul><ul><li>Important to avoid false positive test , i.e., reduce unnecessary investigations. </li></ul>
  9. 9. Colorectal cancer - Screening <ul><li>Screening does not reduce the incidence. </li></ul><ul><li>Data on survival and stage are difficult to interpret; ( length time bias and lead-time bias ). </li></ul><ul><li>Mortality the ‘true’ endpoint </li></ul><ul><li>Risk for selection bias ( randomised trials preferable). </li></ul>
  10. 10. A B Detectable by screening Clinically detectable Length biased sampling Time
  11. 11. Length time bias <ul><li> X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul>
  12. 12. Time A B C D The disease starts Detectable Clinically presented Death Lead time Lead time bias
  13. 13. Lead time bias <ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul><ul><li>X </li></ul>
  14. 14. Prevention Cure Early diagnosis
  15. 15. Colorectal cancer <ul><li>Prevention </li></ul><ul><li>Changing life style ? </li></ul><ul><li>No </li></ul>
  16. 16. Colorectal cancer <ul><li>Chemo - prevention ? </li></ul><ul><li>ASA </li></ul><ul><li>Sulindac </li></ul><ul><li>COX - 2 inhibitors </li></ul>
  17. 17. Colorectal cancer <ul><li>Cure </li></ul><ul><li>More effective treatment ? </li></ul><ul><li>Yes </li></ul>
  18. 19. Colorectal cancer <ul><li>Early diagnosis </li></ul><ul><li>Screening ? </li></ul><ul><li>Yes </li></ul>
  19. 20. Colorectal cancer - Screening <ul><li>Identify risk groups </li></ul><ul><li>Inflammatory bowel disease </li></ul><ul><li>Polyposis coli </li></ul><ul><li>Cancer family syndrome </li></ul><ul><li>Known colorectal cancer </li></ul><ul><li>Known adenomas </li></ul>
  20. 21. Colorectal cancer - Screening <ul><li>Inflammatory bowel disease </li></ul><ul><li>Pancolitis and low age at diagnosis </li></ul><ul><li>Family history of colorectal cancer </li></ul><ul><li>Sclerotic cholangitis </li></ul><ul><li>Best prevention is </li></ul><ul><li>Surgery ! </li></ul>
  21. 22. Colorectal cancer - Screening <ul><li>Familiar polyposis coli </li></ul><ul><li>All known families in register </li></ul><ul><li>Early endoscopy </li></ul><ul><li>Gene - mapping </li></ul><ul><li>Surgery when adenomas occur </li></ul>
  22. 23. Colorectal cancer - Screening <ul><li>Cancer family syndrome HNPCC </li></ul><ul><li>A rare condition ? </li></ul><ul><li>Gene - mapping </li></ul><ul><li>Right - sided colon cancer </li></ul><ul><li>Low age at diagnosis </li></ul><ul><li>Ovarian and uterus cancer </li></ul>
  23. 24. Colorectal cancer - Screening <ul><li>Known colorectal cancer </li></ul><ul><li>A ‘clean’ colon perioperatively </li></ul><ul><li>Colonoscopy every 5th year </li></ul><ul><li>Metachronous cancer ( < 3%) </li></ul><ul><li>Selection due to age </li></ul>
  24. 25. Colorectal cancer - Screening <ul><li>Known adenomas </li></ul><ul><li>‘ Clean’ the colon once </li></ul><ul><li>‘ High-risk’; - treat as a cancer </li></ul><ul><li>‘ Low-risk’; - no more follow-up </li></ul><ul><li>Selection due to age </li></ul>
  25. 26. Colorectal cancer - Screening <ul><li>Known adenomas </li></ul><ul><li>‘ High - risk’ group </li></ul><ul><li>> 3 adenomas </li></ul><ul><li>> 5 hyperplastic polyps in rectum </li></ul><ul><li>Size > 1 cm </li></ul><ul><li>Tubulovillous or villous </li></ul><ul><li>Dysplasia; severe or malignant </li></ul>
  26. 27. Colorectal cancer - Screening <ul><li>Known adenomas </li></ul><ul><li>‘ Low - risk’ group </li></ul><ul><li>< 3 adenomas </li></ul><ul><li>< 5 hyperplastic polyps in rectum </li></ul><ul><li>Size < 1 cm </li></ul><ul><li>Tubular </li></ul><ul><li>Dysplasia; mild or moderate </li></ul>
  27. 28. Screening för kolorektal cancer <ul><li>FOBT </li></ul><ul><li>Tumörmarkörer i feaces </li></ul><ul><li>Skopier </li></ul>
  28. 29. Screening för kolorektal cancer <ul><li>EU rekommenderar screening </li></ul><ul><li>Riktlinjerna FoU </li></ul><ul><li>FOBT ej FoU </li></ul><ul><li>Skopier </li></ul>
  29. 30. Colorectal cancer - Screening <ul><li>Faecal occult blood testing </li></ul><ul><li>Low sensitivity </li></ul><ul><li>40 % cancer missed </li></ul><ul><li>80 % adenomas missed </li></ul><ul><li>‘ Late stage’ lesions bleed </li></ul><ul><li>Frequent testing but inexpensive </li></ul>
  30. 31. Colorectal cancer - Screening <ul><li>Faecal occult blood testing </li></ul><ul><li>Minnesota - trial USA </li></ul><ul><li>Funen - trial Denmark </li></ul><ul><li>Nottingham - trial UK </li></ul><ul><li>Gothenburg - trial Sweden </li></ul>
  31. 32. FOBT Screening - mortality from CRC Heitson et an. Cochrane Database of Systematic Reviews 2007
  32. 33. FOBT screening - total mortality Heitson et an. Cochrane Database of Systematic Reviews 2007
  33. 34. Colorectal cancer - Screening <ul><li>Faecal occult blood testing </li></ul><ul><li>What do we know from these trials ? </li></ul><ul><li>There is a survival benefit ! </li></ul><ul><li>What type of test ? </li></ul><ul><li>Annually or biannually ? </li></ul>
  34. 35. Colorectal cancer - Screening <ul><li>Flexible sigmoidoscopy </li></ul><ul><li>Case-control studies </li></ul><ul><li>J Clin Epidemiol 1988;41:427-34 </li></ul><ul><li>N Engl J Med 1992;326:653-7 </li></ul><ul><li>J Natl Cancer Inst 1992;84:1572-5 </li></ul>
  35. 36. Colorectal cancer - Screening <ul><li>Flexible sigmoidoscopy </li></ul><ul><li>Rationale </li></ul><ul><li>Single sigmoidoscopy at age 60 </li></ul><ul><li>5 % of colorectal cancers occur before the age of 50 </li></ul><ul><li>4 % between ages 50-55 years </li></ul>
  36. 37. Colorectal cancer - Screening <ul><li>Flexible sigmoidoscopy </li></ul><ul><li>Rationale </li></ul><ul><li>Cancers start as an adenoma </li></ul><ul><li>Small adenomas don't bleed </li></ul><ul><li>Treatment immediately </li></ul>
  37. 38. Colorectal cancer - Screening <ul><li>Flexible sigmoidoscopy </li></ul><ul><li>Rationale </li></ul><ul><li>Identify the ‘high’ and ‘low risk’ patient </li></ul><ul><li>Colonoscopy for a ‘high risk’ patient </li></ul><ul><li>Follow the ‘high risk’ group every 5th year </li></ul>
  38. 39. Flex-sig screening - CRC mortality Atkin et al, Lancet 2010
  39. 40. Colorectal cancer - Screening <ul><li>Colonoscopy once ? </li></ul><ul><li>Why not ! </li></ul>
  40. 41. Colorectal cancer - Screening <ul><li>Colonoscopy once </li></ul><ul><li>Incidence Adenomas </li></ul><ul><li>Cancers </li></ul><ul><li> Age 50 60 70 </li></ul>
  41. 42. Colorectal cancer - Screening <ul><li>NordICC </li></ul><ul><li>Norway, Sweden </li></ul><ul><li>Poland, Holland </li></ul><ul><li>Baltic states </li></ul><ul><li> 50.000 </li></ul>
  42. 43. Colorectal cancer - Screening <ul><li>FOB - testing </li></ul><ul><li>the only evidence </li></ul><ul><li>based technique ! </li></ul>
  43. 44. Colorectal cancer - Screening <ul><li>How to </li></ul><ul><li>Implement </li></ul><ul><li>FOBT – testing ? </li></ul>
  44. 45. Colorectal cancer - Screening <ul><li>How to continue </li></ul><ul><li>Implement it slowly </li></ul><ul><li>Check quality </li></ul><ul><li>Must be able to evaluate </li></ul><ul><li>Surrogate end - points </li></ul><ul><li>Must be able to stop the process </li></ul>
  45. 47. Colorectal cancer - Screening <ul><li>Stop the experiment </li></ul><ul><li>if the endpoints </li></ul><ul><li>are not reached </li></ul>
  46. 48. Colorectal cancer - Screening <ul><li>Do we know the endpoints ? </li></ul><ul><li>We can use surrogate endpoints </li></ul>
  47. 49. Colorectal cancer - Screening <ul><li>Surrogate endpoints </li></ul><ul><li>Compliance  60 % </li></ul><ul><li> Pos. pred. value FOB - test  12 % </li></ul><ul><li>Completion rate colonoscopy  85 % </li></ul><ul><li>Complication at colonoscopy  0.02 % </li></ul><ul><li>Stage I or II cancer  55 % </li></ul>

×