Jasper Vleugels PhD-student AMC Workshop 24-10-2016 Jasper Vleugels PhD-student AMC
Program Introduction Training differentiation Test
Program Introduction Training differentiation Test
Introduction Benign Malignant TP53 18q21 (DCC, SMAD-2/4) TGF-ßRII K-RAS TP53 18q21 (DCC, SMAD-2/4) TGF-ßRII Normal epithelium Aberrant crypt focus (ACF) Adenoma Adenocarcinoma APC mutation Benign Malignant Adapted from from Fearon and Vogelstein et al. Cell 1990, Wilson et al. Gastroenterology 2004
Introduction Benign Malignant TP53 18q21 (DCC, SMAD-2/4) TGF-ßRII K-RAS TP53 18q21 (DCC, SMAD-2/4) TGF-ßRII Normal epithelium Aberrant crypt focus (ACF) Adenoma Adenocarcinoma APC mutation Benign Malignant Adapted from from Fearon and Vogelstein et al. Cell 1990, Wilson et al. Gastroenterology 2004
Background Polyp subtypes: Malignant polyp (contains focus of CRC) Potential harmfull polyp (neoplastic): Adenoma Sessile serrated polyp Harmless polyp (non-neoplastic): Hyperplastic polyp
Background Lifetime risk CRC approximately 5%1 Colonoscopy with polypectomy reduces incidence and mortality of CRC2 Recently Dutch nationwide population screening has started with FIT3 1 Edwards et al. Cancer 2010 2 Zauber et al. New England Journal of Medicine 2014 3 http://www.rivm.nl/Onderwerpen/B/Bevolkingsonderzoek_darmkanker
Background
Background
Background
Background
Background > 90% of polyps detected at screening colonoscopy are small (6-9mm) or diminutive (≤5 mm)1-3 These lesions rarely contain cancer – 0-0.2% for adenomas 6-9mm and 0-0.1% for those <5mm1,3 1Lieberman et al. Gastroenterology 2008 2Chen et al. Am J Gastroenterol 2007 3Rex et al. Am J Gastroenterol 2009
Background Current practice to resect and collect all lesions and send them for histopathology (outcome determines surveillance interval) <5% of tubular adenomas with LGD progress to CRC1 Considerable burden for endoscopist, endoscopy- nurses and pathologist Prolongs procedural time, time to advice surveillance interval and costs 1 Muto et al. Cancer 1975
Optical diagnosis Expert endoscopists accurate endoscopic differentiation in 93-94% between neoplastic and non-neoplastic lesions using NBI1,2 1Rex et al. Gastroenterology 2009 2Ignjatovic et al. Lancet Oncology 2009
Narrow band imaging
Background
Background
Consequences of optical diagnosis Adenomas would be resected but would not need to be retrieved and sent for histopathology, saving time. In addition, patients could be given a surveillance interval immediately following the colonoscopy (again leading to savings in time and cost)1,2 Hyperplastic polyps in the rectum and sigmoid, which have no malignant potential could be left in situ (reducing the risks associated with polypectomy)1,2 1 Rex et al. ASGE PIVI guideline. Gastrointestinal Endoscopy 2012 2 Hassan et al. ESGE advanced endoscopic imaging guideline. Endoscopy 2014
Background Not all lesions can be assessed endoscopically
Background Not all lesions can be assessed endoscopically
Potential effect of optical diagnosis Disadvantages: Slight chance of missing submucosal-invasion (carcinoma) in a small polyp Untill now, optical diagnosis is only reliable when performed by experts
DISCOUNT1 1 Kuiper et al. Clinical Gastroenterology and Hepatology 2012
DISCOUNT1 1 Kuiper et al. Clinical Gastroenterology and Hepatology 2012
Program Introduction Training differentiation Test