Impact of Chromoscopy on Adenoma Detection in Patients With Lynch Syndrome: A Prospective, Multicenter, Blinded, Tandem Colonoscopy Study

Abstract

In Lynch syndrome, fl at and diminutive adenomas are particularly prone to malignant transformation, but they can be missed by standard colonoscopy. It is not known whether chromocolonoscopy is able to detect more adenomas than standard colonoscopy in patients with Lynch syndrome. METHODS:We conducted a prospective, multicenter, randomized trial to compare standard colonoscopy with standard colonoscopy followed by pancolonic chromoscopy with indigo carmine in patients with a proven germline mutation in a mismatch-repair gene related to Lynch syndrome and who were undergoing screening or surveillance colonoscopy. Standard colonoscopy was used fi rst to detect visible lesions. Colonoscopy with chromoscopy was then performed by a second gastroenterologist (blinded to the fi ndings of the fi rst colonoscopy) to detect additional lesions. The primary end point was the number of patients in whom at least one adenoma was detected. RESULTS:A total of 78 eligible patients (median age, 45 years) were enrolled at 10 centers from July 2008 to August 2009. Signifi cantly more patients with at least one adenoma were identifi ed by chromocolonoscopy (32/78 (41%)) than by standard colonoscopy (18/78 (23%); P <0.001). The percentage of patients in whom at least one additional adenoma was detected during the chromoscopy was 31% (24/78). Overall, chromocolonoscopy plus colonoscopy detected a total of 55 adenomas in 32 patients (mean number of adenomas detected per patient: 0.7 vs. standard colonoscopy alone: 0.3; P <0.001). CONCLUSION: The results support the proposition that chromocolonoscopy may signifi cantly improve the detection rate of colorectal adenomas in patients undergoing screening or surveillance colonoscopy for Lynch syndrome.

S3-Leitlinie – Kolorektales Karzinom

“…Bei Patienten mit Colitis ulcerosa [458 -462] oder HNPCC [463,464] ist eine höhere Detektionsrate neoplastischer Läsionen durch Chromoendoskopie wahrscheinlich, allerdings ohne bewiesenen Effekt auf den Gesamt-Outcome [462]. Es ist bisher nicht geklärt, ob die Erkennung höherer Raten vorwiegend kleiner Veränderungen dem Patienten nutzen und den erhöhten Zeitaufwand der direkten Chromoendoskopie rechtfertigen.…”

Hereditary gastrointestinal cancers: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up†

“…Chromoendoscopy with indigo carmine added to the standard colonoscopy has been shown to be substantially more effective than colonoscopy alone in LS individuals [26]. High-quality colonoscopy carried out in dedicated centres is advised [IV, C].…”

Hereditary Cancer Syndromes—A Primer on Diagnosis and Management, Part 2: Gastrointestinal Cancer Syndromes

“…Existing studies have limited generalizability because of their retrospective nature or small sample size. 95,96 The European Society of Gastrointestinal Endoscopy does recommend using chromoendoscopy over white-light imaging in patients with established or suspected LS. 97 Larger prospective trials using highdefinition colonoscopes with assessment of long-term outcomes are needed before routine use of chromoendoscopy in patients with LS can be added to US guidelines.…”