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Narrow Band Imaging in Barrett’s Esophagus
CLINICAL GASTROENTEROLOGY AND HEPATOLOGY 2005;3:S21–S22
Narrow Band Imaging in Barrett’s Esophagus PRATEEK SHARMA Division of Gastroenterology and Hepatology, University of Kansas School of Medicine, Kansas City, Missouri
Barrett’sesophagus is the premalignant lesion for esophageal and esophagogastric junction adenocarcinoma. Progression of Barrett’s esophagus to dysplasia and cancer can occur, thus requiring endoscopy with random biopsy examinations. Currently, the diagnosis of metaplastic and dysplastic mucosa within the esophagus requires endoscopy with biopsy examination of abnormal-appearing tissue. The presence of intestinal metaplasia and dysplasia within the esophagus often is patchy, and our current practices of performing standard endoscopy with random biopsy examinations are inaccurate. Narrow band imaging is among several tools used in the esophagus to improve detection of Barrett’s esophagus and associated dysplasia. Current studies show that these techniques are promising, although the results still are preliminary.
he incidence of esophageal adenocarcinoma continues to increase in the United States and the Western world. The 5-year survival rate for this cancer still is very dismal.1 Screening for Barrett’s esophagus at the present time requires an upper endoscopy and esophageal biopsy examination. Barrett’s esophagus is recognized as the presence of columnar mucosa within the esophagus, and biopsy specimens are obtained for the histologic confirmation of specialized intestinal metaplasia. However, biopsy specimens from short segments or tongues of columnar mucosa generally reveal intestinal metaplasia in only 40%– 60% of patients.2 Similarly, the presence of dysplasia or early adenocarcinoma within a segment of Barrett’s esophagus is patchy and focal. Standard endoscopy and random biopsy examinations may fail to detect these lesions.
T
Narrow-Band Imaging Narrow-band imaging (NBI) recently was developed to improve the quality of endoscopic images and to enhance the microvasculature and visualization of its mucosal pit pattern.3 The sequential lighting method in videoendoscopes has a rotation disk with red, green, and blue optical filters in front of a white light source (xenon lamp). NBI is a technique that changes these optical filters to spectral narrow-band filters. The penetration depth of light is dependent on its wavelength, with
visible blue light (415 nm) penetrating only superficial areas of the tissue (narrow band). Therefore, the use of blue light alone with the help of a special NB filter can enable imaging of the superficial tissue surface structures. Preliminary results using NBI have been reported recently4 and presented at Digestive Diseases Week in 2003 and 2004.5–9
Kansas City Experience Using Narrow-Band Imaging in Patients With Barrett’s Esophagus We recently used NBI endoscopy in patients with Barrett’s esophagus presenting for surveillance endoscopy.4,8 Patients are evaluated with a standard magnification endoscope (GIF Q240Z, 115⫻; Olympus, Melville, NY) using a NBI light source. NBI imaging provides a striking contrast between the columnar and squamous mucosa in the distal esophagus without using dye spray (ie, chromoscopy) (Figure 1). Specific capillary and mucosal pit patterns have been observed within the segment of Barrett’s esophagus. Areas of nondysplastic tissue have fine capillary patterns with a normal size and distribution of these fine blood vessels; in contrast, areas harboring high-grade dysplasia have an abnormal capillary pattern with an increased number, size, and dilation of the fine capillaries. NBI thus provides a detailed image of the capillary patterns in patients with Barrett’s esophagus. Recently, the use of NBI in patients with Barrett’s esophagus has been reported by other investigators who indicated the presence of neoplastic lesions in patients with abnormally increased and dilated capillaries seen on NBI imaging.7
Conclusions Several promising endoscopic imaging techniques including magnification endoscopy, NBI, and others currently are being developed for the detection of metaplasia © 2005 by the American Gastroenterological Association
1542-3565/05/$30.00 PII: 10.1053/S1542-3565(05)00281-8
S22
PRATEEK SHARMA
CLINICAL GASTROENTEROLOGY AND HEPATOLOGY Vol. 3, No. 7
these endoscopic techniques should be validated in large, multicenter clinical trials.
References
Figure 1. Endoscopic appearance of the proximally displaced squamocolumnar junction and columnar mucosa as visualized by narrow band imaging.
(screening) and dysplasia/cancer (surveillance). These new technologies represent a significant improvement over standard endoscopy for diagnosing metaplasia and dysplasia and even early cancer. NBI technology is undergoing rapid development and holds promise for the accurate detection of Barrett’s metaplasia and dysplasia. At this point, standard endoscopy with random biopsy examination remains the gold standard. However, these new endoscopic techniques are likely to modify clinical practice in the near future. The preliminary results using
1. Brown LM, Devesa SS. Epidemiologic trends in esophageal and gastric cancer in the United States. Surg Oncol Clin N Am 2002; 11:235–256. 2. Sharma P, Morales TG, Sampliner RE. Short segment Barrett’s esophagus: the need for standardization of the definition and of endoscopic criteria. Am J Gastroenterol 1998;93:1033–1036. 3. Gono K, Obi T, Yamaguchi M, et al. Appearance of enhanced tissue features in narrow-band endoscopic imaging. J Biomed Opt 2004; 9:568 –577. 4. Hamamoto Y, Endo T, Nosho K, et al. Usefulness of narrow-band imaging endoscopy for diagnosis of Barrett’s esophagus. J Gastroenterol 2004;39:14 –20. 5. Sharma P, McGregor D, Cherian R, et al. Use of narrow band imaging, a novel imaging technique, to detect intestinal metaplasia and high-grade dysplasia in patients with Barrett’s esophagus. Gastrointest Endosc 2003;57:AB77. 6. Kara MA, Bergman JJ, Fockens P, et al. Narrow band imaging for improved mucosal pattern recognition in Barrett’s esophagus. Gastrointest Endosc 2003;57:AB176. 7. Fujisaki J, Saito N, Matsuda K, et al. Clinicopathological analysis of superficial type Barrett’s esophageal cancer and efficacy of magnifying endoscopy with narrow band image system for specialized columnar epithelium. Gastrointest Endosc 2003;57:AB179. 8. Kara M, Ennahachi M, Fockens P, et al. Narrow-band imaging (NBI) in Barrett’s esophagus (BE): what features are relevant for the detection of high-grade dysplasia (HGD) and early cancer (EC)? Gastroenterology 2004;126:A-50. 9. Sharma P, Mathur S, Dixon A, et al. Narrow band imaging endoscopy for the detection of dysplastic and non dysplastic Barrett’s esophagus. Gastrointest Endosc 2004;59:AB263.
Address requests for reprints to: Prateek Sharma, MD, Division of Gastroenterology and Hepatology, University of Kansas School of Medicine, VA Medical Center, Kansas City, Missouri. e-mail: [email protected]; fax: (816) 922-4692.
Narrow Band Imaging in Barrett’s Esophagus PRATEEK SHARMA Division of Gastroenterology and Hepatology, University of Kansas School of Medicine, Kansas City, Missouri
Barrett’sesophagus is the premalignant lesion for esophageal and esophagogastric junction adenocarcinoma. Progression of Barrett’s esophagus to dysplasia and cancer can occur, thus requiring endoscopy with random biopsy examinations. Currently, the diagnosis of metaplastic and dysplastic mucosa within the esophagus requires endoscopy with biopsy examination of abnormal-appearing tissue. The presence of intestinal metaplasia and dysplasia within the esophagus often is patchy, and our current practices of performing standard endoscopy with random biopsy examinations are inaccurate. Narrow band imaging is among several tools used in the esophagus to improve detection of Barrett’s esophagus and associated dysplasia. Current studies show that these techniques are promising, although the results still are preliminary.
he incidence of esophageal adenocarcinoma continues to increase in the United States and the Western world. The 5-year survival rate for this cancer still is very dismal.1 Screening for Barrett’s esophagus at the present time requires an upper endoscopy and esophageal biopsy examination. Barrett’s esophagus is recognized as the presence of columnar mucosa within the esophagus, and biopsy specimens are obtained for the histologic confirmation of specialized intestinal metaplasia. However, biopsy specimens from short segments or tongues of columnar mucosa generally reveal intestinal metaplasia in only 40%– 60% of patients.2 Similarly, the presence of dysplasia or early adenocarcinoma within a segment of Barrett’s esophagus is patchy and focal. Standard endoscopy and random biopsy examinations may fail to detect these lesions.
T
Narrow-Band Imaging Narrow-band imaging (NBI) recently was developed to improve the quality of endoscopic images and to enhance the microvasculature and visualization of its mucosal pit pattern.3 The sequential lighting method in videoendoscopes has a rotation disk with red, green, and blue optical filters in front of a white light source (xenon lamp). NBI is a technique that changes these optical filters to spectral narrow-band filters. The penetration depth of light is dependent on its wavelength, with
visible blue light (415 nm) penetrating only superficial areas of the tissue (narrow band). Therefore, the use of blue light alone with the help of a special NB filter can enable imaging of the superficial tissue surface structures. Preliminary results using NBI have been reported recently4 and presented at Digestive Diseases Week in 2003 and 2004.5–9
Kansas City Experience Using Narrow-Band Imaging in Patients With Barrett’s Esophagus We recently used NBI endoscopy in patients with Barrett’s esophagus presenting for surveillance endoscopy.4,8 Patients are evaluated with a standard magnification endoscope (GIF Q240Z, 115⫻; Olympus, Melville, NY) using a NBI light source. NBI imaging provides a striking contrast between the columnar and squamous mucosa in the distal esophagus without using dye spray (ie, chromoscopy) (Figure 1). Specific capillary and mucosal pit patterns have been observed within the segment of Barrett’s esophagus. Areas of nondysplastic tissue have fine capillary patterns with a normal size and distribution of these fine blood vessels; in contrast, areas harboring high-grade dysplasia have an abnormal capillary pattern with an increased number, size, and dilation of the fine capillaries. NBI thus provides a detailed image of the capillary patterns in patients with Barrett’s esophagus. Recently, the use of NBI in patients with Barrett’s esophagus has been reported by other investigators who indicated the presence of neoplastic lesions in patients with abnormally increased and dilated capillaries seen on NBI imaging.7
Conclusions Several promising endoscopic imaging techniques including magnification endoscopy, NBI, and others currently are being developed for the detection of metaplasia © 2005 by the American Gastroenterological Association
1542-3565/05/$30.00 PII: 10.1053/S1542-3565(05)00281-8
S22
PRATEEK SHARMA
CLINICAL GASTROENTEROLOGY AND HEPATOLOGY Vol. 3, No. 7
these endoscopic techniques should be validated in large, multicenter clinical trials.
References
Figure 1. Endoscopic appearance of the proximally displaced squamocolumnar junction and columnar mucosa as visualized by narrow band imaging.
(screening) and dysplasia/cancer (surveillance). These new technologies represent a significant improvement over standard endoscopy for diagnosing metaplasia and dysplasia and even early cancer. NBI technology is undergoing rapid development and holds promise for the accurate detection of Barrett’s metaplasia and dysplasia. At this point, standard endoscopy with random biopsy examination remains the gold standard. However, these new endoscopic techniques are likely to modify clinical practice in the near future. The preliminary results using
1. Brown LM, Devesa SS. Epidemiologic trends in esophageal and gastric cancer in the United States. Surg Oncol Clin N Am 2002; 11:235–256. 2. Sharma P, Morales TG, Sampliner RE. Short segment Barrett’s esophagus: the need for standardization of the definition and of endoscopic criteria. Am J Gastroenterol 1998;93:1033–1036. 3. Gono K, Obi T, Yamaguchi M, et al. Appearance of enhanced tissue features in narrow-band endoscopic imaging. J Biomed Opt 2004; 9:568 –577. 4. Hamamoto Y, Endo T, Nosho K, et al. Usefulness of narrow-band imaging endoscopy for diagnosis of Barrett’s esophagus. J Gastroenterol 2004;39:14 –20. 5. Sharma P, McGregor D, Cherian R, et al. Use of narrow band imaging, a novel imaging technique, to detect intestinal metaplasia and high-grade dysplasia in patients with Barrett’s esophagus. Gastrointest Endosc 2003;57:AB77. 6. Kara MA, Bergman JJ, Fockens P, et al. Narrow band imaging for improved mucosal pattern recognition in Barrett’s esophagus. Gastrointest Endosc 2003;57:AB176. 7. Fujisaki J, Saito N, Matsuda K, et al. Clinicopathological analysis of superficial type Barrett’s esophageal cancer and efficacy of magnifying endoscopy with narrow band image system for specialized columnar epithelium. Gastrointest Endosc 2003;57:AB179. 8. Kara M, Ennahachi M, Fockens P, et al. Narrow-band imaging (NBI) in Barrett’s esophagus (BE): what features are relevant for the detection of high-grade dysplasia (HGD) and early cancer (EC)? Gastroenterology 2004;126:A-50. 9. Sharma P, Mathur S, Dixon A, et al. Narrow band imaging endoscopy for the detection of dysplastic and non dysplastic Barrett’s esophagus. Gastrointest Endosc 2004;59:AB263.
Address requests for reprints to: Prateek Sharma, MD, Division of Gastroenterology and Hepatology, University of Kansas School of Medicine, VA Medical Center, Kansas City, Missouri. e-mail: [email protected]; fax: (816) 922-4692.