A randomized comparison of methylene blue-directed biopsy versus conventional four-quadrant biopsy for the detection of intestinal metaplasia and dysplasia in patients with long-segment Barrett's esophagus.

OBJECTIVES: Methylene blue (MB) selectively stains specialized intestinal metaplasia (SIM) and may assist in surveying a columnar-lined esophagus for Barrett's esophagus associated dysplasia. METHODS: This is a prospective, randomized crossover study comparing 4-quadrant random biopsies (4QB) versus MB-directed biopsies for the detection of SIM and dysplasia in 48 patients with long segment Barrett's esophagus (LSBE). Patients randomly underwent two endoscopies over a 4-wk time period with either 4QB or MB-directed biopsies as their first or second exam. Our aim was to correlate stain intensity with histology. RESULTS: The sensitivity of MB for SIM and dysplasia was 75.2% and 83.1%, respectively. The yield of 4QB for identifying nondysplasia SIM was 57.6% (523/917) and for dysplasia was 12% (111/917). Dark staining was significantly associated with histologic grade (P < 0.007). The final diagnosis was correct in 43 (90%) patients using MB and in 45 (94%) using 4QB. The 4QB technique missed dysplasia in 3 of 21 patients while MB biopsies missed dysplasia in 5 of 21 patients. The discordance between the two techniques was not significant (P= 0.727, McNemar's test). The mean number of biopsies taken during 4QB was 18.92 +/- 6.36 and with MB was 9.23 +/- 2.89 (P < 0.001). CONCLUSION: MB requires significantly fewer biopsies than 4QB to evaluate for SIM and dysplasia. Dark staining correlates more with HGD than LGD in our experience. While MB is not more accurate than 4QB, MB may help to define areas to target for biopsy during surveillance endoscopy in patients with LSBE.

Use of methylene blue for detection of specialized intestinal metaplasia in GERD patients presenting for screening upper endoscopy.

The ability of randomly obtained biopsy specimens to identify intestinal metaplasia in the distal esophagus is low. Use of vital staining has been suggested, as stains are taken up by areas histologically identified as specialized intestinal metaplasia (SIM). This study evaluated the role of methylene blue (MB) staining for identification of SIM in GERD patients undergoing a screening endoscopy. Chromoendoscopy of the distal esophagus using 1% MB was performed on 52 GERD patients presenting for their first endoscopy. Biopsies were obtained from areas that were stained darkly, stained lightly, unstained, or macroscopically abnormal. In patients with no MB staining, four-quadrant biopsy of the distal esophagus was performed. Twenty-seven patients (52%) showed staining with MB, while 25 patients did not. Two hundred sixty-six biopsies were obtained. SIM was detected in 11 (21%) subjects (SIM+) but not in the remaining 41 (SIM-). One hundred sixty-five biopsies were unstained (25 SIM+, 140 SIM-) and 101 were stained (12 SIM+, 89 SIM-). The per-biopsy sensitivity and specificity of MB for detection of SIM were 32.4 and 85%, while the per-patient sensitivity and specificity were 63.3 and 51.2%. MB staining for detection of SIM in GERD patients without a macroscopic appearance suggestive of a columnar-lined esophagus is a poor screening tool for SIM.