WEO CRC SC Meeting. Barcelona, Spain October 23, 2015

Transcription

1 WEO CRC SC Meeting Barcelona, Spain October 23, 2015

2 Identification of serrated polyposis syndrome in the context of population-based CRC screening programs Evelien Dekker Academic Medical Center Amsterdam, NL

3 Serrated neoplasia pathway ±15-30% of all colorectal cancers (CRC) arise from serrated polyps (SP) Evelien Dekker

4 Serrated neoplasia pathway ±15-30% of all colorectal cancers (CRC) arise from serrated polyps (SP) Relatively large part of interval cancers originate from SPs (BRAF, CIMP-high etc) IJspeert Nat Rev Gastro 2015, Nishihara NEJM 2013

5 Prevention of CRC during colonoscopy Detect and resect: All adenomas Serrated polyps: Sessile serrated adenomas/polyps: all Hyperplastic polyps: large and/or right-sided Traditional serrated adenomas Evelien Dekker

6 Serrated polyps: difficult to diagnose By endoscopist By pathologist..

7 Endoscopist Detection, recognition, understanding malignant potential, treatment..

8 Pathologist Adenoma (AD) Sessile serrated adenoma (SSA) Hyperplastic polyp (HP) Accuracy,.. inter-observer & intra-observer accuracy

9 Detection rates of SPs vary.. Kahi, CGH 2011

10 Inadequate detection of relevant SPs Clinically relevant SP = all SPs except HPs 5mm in the rectosigmoid Routine practice Comparison of the performance in SP detection between the 25% highest and 75% lowest performers Detection rate high-performers (%) Detection rate low-performers (%) Corrected OR (95% CI) p-value Relevant SPs 1-5mm 6-9mm >10mm ( ) 1.41 ( ) 2.68 ( ) 2.64 ( ) < <0.001 <0.01 IJspeert, GIE 2015

11 Serrated polyps - underdiagnosis Minimal detection standards can be set No data on SPDR and interval carcinomas Evelien Dekker

12 Serrated polyposis syndrome Also patients with multiple serrated polyps: serrated polyposis syndrome

13 Evelien Dekker

14 Serrated polyposis syndrome Serrated polyposis syndrome (SPS) is characterized by multiple SPs Germline mutation for SPS not yet identified WHO-definition SPS WHO 1 WHO 2 WHO 3 5 SP proximal to rectosigmoid, 2 of which are 10mm in size Any SP proximal to rectosigmoid and a first degree relative with SPS 20 SP of any size distributed throughout the colon Evelien Dekker

15 Background Patients with serrated polyposis syndrome (SPS) are at increased risk of CRC Hyman, Dis Colon & Rectum 2004, 2 Chow, Gastro 2006, 3 Boparai, Gut 2010, 4 Edelstein, Gut 2013

16 Background Patients with serrated polyposis syndrome (SPS) are at increased risk of CRC 1-4 When appropriate surveillance: risk significantly reduced 5 So: detection is important 1 Hyman, Dis Colon & Rectum 2004, 2 Chow, Gastro 2006, 3 Boparai, Gut 2010, 4 Edelstein, Gut 2013, 5 Hazewinkel, Gastro 2014

17 Prevalence of SPS underestimated 529 consecutive patients referred to tertiary center for polyp-resection 20 (4%) met WHO-criteria for SPS; only one case suspected 1. 1 Verapamulli GIE Evelien Dekker

18 Prevalence of SPS Prevalence of SPS in general population largely unknown

19 Prevalence of SPS Prevalence of SPS in general population largely unknown Recent review in Endoscopy: few studies 1. 1 Van Herwaarden Endoscopy 2015

20 Prevalence of SPS sigmo colo FOBT. 1 Van Herwaarden Endoscopy 2015.

21 Prevalence of SPS FOBT: %: selection based on blood in stool 1 Screening colonoscopy: % 1 However, most patients with SPS are diagnosed during surveillance 2,3!. 1 Van Herwaarden Endoscopy 2015, 2 Edelstein GUT 2013, 3 Vemulapalli GIE 2012.

22 European analysis Aim: To evaluate and compare the prevalence of SP subtypes and SPS among European colonoscopy cohorts Design: International multicentre prospective observational design Inclusion criteria: Screening or case-mix cohorts of >1000 colonoscopies Colonoscopies performed 2009 Patient aged 50 years Polyp diagnosis based on histopathology. 1 IJspeert, abstract UEGW 2015

23 Baseline characteristics UK Spain Italy-1 Italy-2 NL-1 NL-2 Poland Cohort type gfobt FIT FIT Case-mix Case-mix Primary Primary colonoscopy colonoscopy Cohort size Age in years Male gender 58% 55% 55% 50% 48% 51% 47% Quality indicators GI-pathologist N/A Yes N/A Yes Yes Yes Yes Cecal intubation 97% 97% 91% 91% 96% 99% 98% Adequate bowel preparation 97% 95% 94% 85% 89% 92% 92% ADR 43% 47% 48% 32% 42% 30% 32%. 1 IJspeert, abstract UEGW 2015

24 Prevalence of SP overall. 1 IJspeert, abstract UEGW 2015

25 Prevalence of SSA/P. 1 IJspeert, abstract UEGW 2015

26 Prevalence of SPS Patients diagnosed with serrated polyposis syndrome Cohort name UK Spain NL-1 NL-2 Poland Cohort type gfobt FIT Case-mix Primary Primary colonoscopy colonoscopy Cohort size, n Diagnosed with SPS at initial colonoscopy, n (%) 65 (0.03) 28 (0.5) (0.1) Diagnosed with SPS during surveillance, n (%) - 20 (0.3) 15 (0.6) 6 (0.4) - Number needed to screen No data retrieved for the Italy-1 and Italy-2 cohorts. Detection via screening: %, substantial % during surveillance. 1 IJspeert, abstract UEGW 2015

27 In conclusion (1) Serrated polyps are premalignant SPS is high risk syndrome Detection is underestimated: for SPs as well as SPS... leading to interval cancers Detection of multiple SPs -> suspicion of SPS: Surveillance! Optimal prep, your best endoscope, (digital) chromoendoscopy? Evelien Dekker

28 In conclusion (2) Based on prospective (screening-) cohorts: minimal detection standards can be set Increased awareness, training, benchmarking & feedback is needed to achieve optimal efficacy of screening programs in preventing CRC Evelien Dekker

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