Methylene blue-aided chromoendoscopy for the detection of intraepithelial neoplasia and colon cancer in ulcerative colitis.
OBJECTIVE
Timely diagnosis of intraepithelial neoplasias (IN) and colitis-associated colon carcinomas (CRC) is crucially important for the treatment of ulcerative colitis (UC). We performed a randomized, controlled trial to test whether chromoendoscopy (CE) might facilitate early detection of IN and CRC in UC.


METHODS
A total of 263 patients with long-standing UC (>or=8 years) were screened for potential inclusion in the study, 165 of whom were randomized at a 1:1 ratio to undergo conventional colonoscopy or colonoscopy with CE using 0.1% methylene blue. Five mucosal biopsy specimens were taken every 10 cm between the rectum and cecum. Circumscript lesions in the colon were evaluated according to a modified pit pattern classification.


RESULTS
In the CE group, there was a significantly better correlation between the endoscopic assessment of degree (P = 0.0002) and extent (89% vs. 52%; P < 0.0001) of colonic inflammation and the histopathologic findings compared with the conventional colonoscopy group. More targeted biopsies were possible, and significantly more IN were detected in the CE group (32 vs. 10; P = 0.003). Using the modified pit pattern classification, both the sensitivity and specificity for differentiation between non-neoplastic and neoplastic lesions were 93%.


CONCLUSIONS
Based on our prospective randomized trial, CE permits more accurate diagnosis of the extent and severity of the inflammatory activity in UC compared with conventional colonoscopy. In addition, CE with methylene blue is a novel tool for the early detection of IN and CRC in patients with UC. These findings have important implications for medical and surgical interventions.
Kiesslich
Ralf
R
I. Medical Clinic, Johannes Gutenberg University of Mainz, Mainz, Germany. kiesslic@mail.uni-mainz.de
Fritsch
Johannes
J
Holtmann
Martin
M
Koehler
Heinz H
HH
Stolte
Manfred
M
Kanzler
Stephan
S
Nafe
Bernhard
B
Jung
Michael
M
Galle
Peter R
PR
Neurath
Markus F
MF
D000328:Adult; D000368:Aged; D001706:Biopsy; D002278:Carcinoma in Situ / Q000209:etiology / Q000473:pathology*; D003093:Colitis, Ulcerative / Q000150:complications*; D003110:Colonic Neoplasms / Q000209:etiology / Q000473:pathology*; D003113:Colonoscopy / Q000379:methods*; D004396:Coloring Agents; D006801:Humans; D008751:Methylene Blue; D008875:Middle Aged; D010865:Pilot Projects; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012720:Severity of Illness Index
D004396:Coloring Agents; D008751:Methylene Blue