COPENHAGEN — High-resolution, white-light endoscopy was as good as more targeted endoscopy methods for diagnosing high-grade dysplasia or early cancer in patients with Barrett's esophagus, based on study results from 28 patients.
“The ability of an endoscopist to detect lesions in overview is more important than targeted imaging. For detecting lesions in Barrett's esophagus, high-quality, white-light imaging is the most important technique” available today, Dr. Jacques Bergman said at the 13th United European Gastroenterology Week.
Autofluorescence endoscopy using red light may have potential to improve overview detection of dysplasia and early cancer, but this must be proved in further studies, said Dr. Bergman, a gastroenterologist at the Academic Medical Center, Amsterdam, who also has a PhD.
The study he reported tested two other new methods for improving endoscopy sensitivity: indigo carmine chromoendoscopy (ICC), and narrow-band imaging (NBI).
ICC uses indigo carmine stain to improve visualization of dysplasia. NBI uses filters to produce red-, blue-, and green-light images that highlight different aspects of the esophageal mucosa. For example, blue light, with its shorter wavelength, provides good resolution in the superficial mucosa, while red light, with a longer wavelength, better images deeper tissue.
The study included 17 patients who had been referred to the Academic Medical Center because of suspicion of high-grade dysplasia or early cancer, 6 patients who had undergone treatment for high-grade dysplasia, and 5 patients with Barrett's esophagus who were in a routine surveillance program.
The 28 patients were randomized to an initial examination by high-resolution endoscopy with white light, plus either ICC or NBI. The examination took two biopsies from any identified abnormalities plus random biopsies at 2-cm intervals throughout the area affected by Barrett's esophagus. Patients then underwent a second examination 6 weeks later using the alternate imaging method.
The combined imaging and biopsy data were used to make a definitive diagnosis for each patient. Overall, 14 patients were determined to have high-grade dysplasia or early cancer, 9 had low-grade dysplasia, and 5 had no dysplasia.
Of the 14 patients (93%) with high-grade dysplasia or early cancer, 13 (93%) were diagnosed by ICC, compared with 12 (86%) diagnosed with NBI, Dr. Bergman reported.
But the study's aim was to assess the ability of each method to do targeted imaging. By this standard, both methods flagged lesions for biopsy that identified high-grade dysplasia or early cancer in 11 of the 14 patients (79%).
All of these 11 patients were also diagnosed with high-grade dysplasia or early cancer by high-resolution, white-light endoscopy alone, showing that this method is as good as ICC or NBI for the overview identification of significant disease.
“The high sensitivity of white-light endoscopy reduces the potential, added value of ICC and NBI,” Dr. Bergman said.