1. Joint Hospital Surgical Grand Round 19 June 2004

2. Colorectal Polyps Management Dr. Kwong Wing Hang Department of Surgery NDH / AHNH

3. Adenomatous colonic polyp

4. What is the clinical significant value of colorectal adenomatous polyps? Adenomatous polyp is precursor of colorectal cancer Epidemiology Epidemiology Pathology Pathology Adenoma-carcinoma sequence Adenoma-carcinoma sequence

5. Adenoma-Carcinoma sequence Multi-steps and accumulative DNA changes Normal Colonic epithelium Small adenoma Large adenoma Pre-malignant changes Colorectal cancer Invasion APC Ki-ras Smad 4 p53 E-cadherin

6. 95% colorectal cancers arise in benign colonic adenomatous polyps Takes 10 years to become invasive cancer Interruption of adenoma-carcinoma sequence

7. Do all colorectal adenomatous polyps have high malignant potential? Small ( 60) Correa P. Gastroenterology 1979

8. Do all colorectal adenomatous polyps have high malignant potential? Tubular adenoma have low malignant potential Most of them remain static or regress Few will increase in size, develop villous changes, high grade dysplasia and invasive carcinoma Hoff G. Scand J Gastroenterology 1986

9. Advanced adenoma Concept >1cm, villous change, high grade dysplasia, invasive carcinoma US National Polyp Study

10. Natural history of untreated colonic polyps Total 226 patients with polyps >1cm Mean 68 months mean 5.2 surveillance barium enema 83 (37%) polyps enlarged 21 (9%) cancers Stryker SJ. Gastroenterology 1987

11. Natural history of untreated colonic polyps Cumulative risk of malignancy with polyp >1cm at 5, 10, and 20 years was 2.5%, 8% and 24% Stryker SJ. Gastroenterology 1987

12. Management of colorectal polyp Pathological Diagnosis and risks stratification Diagnosis and Endoscopic Polypectomy Follow up surveillance

13. Diagnosis and Surveillance Tools Colonoscopy Vs Double contrast barium enema Colonoscopy more accurate with sensitivity of 94% Barium enema 67% Hogan et al. Gastrointest Endosc 1977

14. Effect of Polypectomy Several Case control studies from US, Norway and Italy demonstrated that Endoscopic polypectomy decreased in incidence and mortality of colorectal cancer Winawer SJ. N Engl J Med 1995 This-Evensen E. Scnd J Gastroenterol 1999 Zauber AG. Gastroenterology 2000

15. Initial Management of Polyps Endoscopic polypectomy Complete colonoscopy to remove all the synchronous adenoma Complete colonoscopy to remove all the synchronous adenoma Achieve detailed histological diagnosis Achieve detailed histological diagnosis

16. Treatment of Small benign polyps Endoscopic polypectomy Electro-cautery Electro-cauterySnaring Hot biopsy

17. Treatment of Large sessile polyps Large sessile polyp (>2cm) contains villous tissue high malignant potential high malignant potential High local recurrence High local recurrence Follow up colonoscopy 3-6 months Surgery

18. Long term results of endoscopic removal of large colorectal adenomas 288 patients with total 302 polyps larger than 3cm removed endoscopically in 12 years 244 sessile and 78 pedunculated Recurrence rate 17% 2 patients developed malignant recurrence U. Seitz. Endoscopy 2003

19. Treatment of Malignant Colonic Polyp Risk of local recurrence and lymph node metastasis vs Risk of Surgery Malignant Polyp with High recurrence risk vs Low recurrence risk Malignant Polyp with High recurrence risk vs Low recurrence risk High surgical risk patient vs Low surgical risk patient High surgical risk patient vs Low surgical risk patient

20. Unfavorable criteria for malignant polyp with high recurrence risk with high recurrence risk Positive margin involvement of resected polyp Positive margin involvement of resected polyp Poorly differentiated Poorly differentiated Presence of vascular or lymphatic invasion Presence of vascular or lymphatic invasion Coutsoftides T. Ann Surg1978

21. Unfavorable criteria for malignant polyp with high recurrence risk Cleveland clinic Without unfavorable criteria Without unfavorable criteria Cranley JP. Gastroenterology 1986 pedunculatedsessile Incidence of residual cancer 0.3%1.5%

22. Unfavorable criteria for malignant polyp with high recurrence risk Italian study Cases with one or more unfavorable criteria Cases with one or more unfavorable criteria Coverlizza S. Cancer 1989 PedunculatedSessile Incidence of residual cancer 8.5%14.4%

23. Management Of Malignant Polyp High recurrent risk malignant polyp Low recurrent risk malignant polyp Low surgical risk patient SurgerySurgeryor FU surveillance High surgical risk patient Endoscopic polypectomy and FU surveillance

24. Post polypectomy Surveillance When?

25. Relative risk of developing colorectal cancer after polypectomy in Mayo clinic Mayo Clin Proc 1986 RR <1cm1 >1cm2.7 No =3 / >3 5

26. 1618 patients in St Mark Hospital, London Atkin WS. N Engl J Med 1992 RR If resected polyp <1cm 1 >1cm or presence of villous tissue 3.6 If number of polyps> 3 6.6

27. US National Polyp Study 7-center trial 1418 patients with at least one newly diagnosed colorectal adenoma after colonoscopy and polypectomy FU colonoscopy at 1 year then 3 years Vs every 3 years

28. US National Polyp Study FU colonoscopy at 1 years and then 3 years FU colonoscopy at 3 years “Recurrent” adenoma 41.7%32-42% Large advanced adenoma 3.3%3.3% Winawer SJ, N Eng J Med 1993

29. Predictive factors - Increase chance of having advanced adenoma if n >/= 3 if n >/= 3 large adenoma >/= 1cm large adenoma >/= 1cm Family history of Colorectal cancer (1st degree relative) Family history of Colorectal cancer (1st degree relative)

30. US National Polyp Prevention Study 479 patients Predictors for advanced metachronous adenoma Multiple adenoma >/=3 Multiple adenoma >/=3 Presence of villous histology Presence of villous histology Van Stolk RU. Gastroenterology 1998

31. Very low risk of recurrent advanced adenoma at 3 years Only one or two small tubular adenoma Only one or two small tubular adenoma No family history of colorectal cancer No family history of colorectal cancer

32. Post Polypectomy surveillance recommendations Complete colonoscopy to clear all polyps Additional clearing exam after resection of a large sessile adenoma or uncertainty of complete resection High risk patients (n>/=3, >/=1cm, villous histology, high grade dysplasia, Family Hx of CR cancer) FU colonoscopy at 3 years FU colonoscopy at 3 years Low risk patient FU colonoscopy at 5 years FU colonoscopy at 5 years

33. Post Polypectomy surveillance recommendations Selected low risk patients may not require follow–up surveillance colonoscopy for advanced age or co- morbidity After one negative follow-up surveillance colonoscopy, subsequent surveillance interval increase to 5 years Surveillance should be discontinued for advanced age or co-morbidity Winawer SJ. Gastroenterology 2003

34. Summary Colorectal polyps Endoscopic polypectomy Benign Malignant Risk stratificationLow riskHigh risk FU Colonoscopy 3 years Fu colonoscopy 5 year High risk malignant polyp Low risk malignant polyp Low surgical risk patient SurgerySurgeryOrSurveillance High surgical risk patient Endoscopic polypectomy Normal FU Colonoscopy Surgery

35. Thank You