Background: Barrett's oesophagus embodies the risk of malignant transformation. High-grade intraepithelial neoplasia and early cancer in Barrett's oesophagus are often discrete or macroscopically occult lesions and show a patchy distribution and therefore, directed biopsies in combination with four-quadrant random biopsies are the gold standard for surveillance.
Aims: The aim of this prospective study was to compare methylene blue staining and random biopsies in patients with early Barrett's neoplasia.
Patients and methods: Eighty-six patients (mean age 65+/-8 years) with histologically proven but macroscopically in evident high-grade intraepithelial neoplasia (n=17) or early cancer in Barrett's oesophagus (n=69) on HR-endoscopy with all together 98 lesions, were included. In the first step, four-quadrant random biopsies were taken during routine endoscopy (group I). In a second step, staining was performed with a 0.5% solution of methylene blue with a spray catheter. Biopsies of focal areas with decreased stain, heterogeneity of stain or absence stain were taken (group II).
Results: In 75/86 patients, high-grade intraepithelial neoplasia or early cancer in Barrett's oesophagus could be diagnosed in the methylene blue group while 56 patients were determined in the random biopsies group (P=0.053). High-grade intraepithelial neoplasia or early cancer was diagnosed in significantly more methylene blue-directed biopsies (80.9% versus 26.4%, P<0.005) and also significantly more lesions could be identified in the methylene blue group (96/98; 98%) while in the random biopsies group only 58/98 lesions (59%) could be localised (P<0.05). When methylene blue was used (1217 versus 562, P<0.0001), the average number of specimens taken with methylene blue per patient was about half of that with random biopsy (6.5 versus 14.1, P<0.0001).
Conclusions: Chromoendoscopy with methylene blue diagnosed significantly more patients and lesions with intraepithelial neoplasia or early cancer in Barrett's oesophagus compared to random biopsies. In addition, significantly less biopsies were needed with methylene blue compared to random biopsies. The use of methylene blue-directed biopsies appears to improve the detection of intraepithelial neoplasia and early cancer in Barrett's oesophagus.