Methylene blue-directed biopsies improve detection of intestinal metaplasia and dysplasia in Barrett's esophagus

Advanced imaging and technology in gastrointestinal neoplasia: summary of the AGA-NCI Symposium October 4-5, 2004

Imaging and other advanced technologies for detection of gastrointestinal cancers are undergoing a major revolution on several fronts. This is facilitated by convergence of key technologies including advanced endoscopic-detection systems, more specific contrast agents, rapid and high-resolution cross-sectional imaging, and miniaturization of construction systems for making all imaging equipment smaller and less invasive. This convergence is occurring along traditional translational research pathways (clinical medicine-molecular biology) as well as nontraditional lines (clinical medicine-optical physics/engineering and molecular biology-optical physics/engineering). These new efforts are producing a wide array of technologies aimed at improving detection, classification, and monitoring of gastrointestinal neoplasia, especially for colorectal and esophageal cancer because of easier accessibility. A critical goal is to detect lesions at their premalignant stages, thereby permitting meaningful intervention. Inspired by these advances, the American Gastroenterological Association and the National Cancer Institute sponsored a symposium held in Bethesda, MD, from October 4-5, 2004, bringing together leading investigators with diverse backgrounds in imaging technology. The aims of this symposium were to summarize the state of the art and priorities for research in the coming decade in the field of imaging and advanced technology for gastrointestinal neoplasia. In this overview, we summarize the salient results of that symposium. The initial sections discuss the major technologies in each area of endoluminal imaging and molecular imaging followed by applications to specific diseases such as Barrett's esophagus and colon neoplasia. Each section focuses on the current state of the art then lists major priorities for research in the field.

Evaluation of sensitivity and inter- and intra-observer variability in the detection of intestinal metaplasia and dysplasia in Barrett's esophagus with enhanced magnification endoscopy

OBJECTIVE

Magnification endoscopy with acetic acid or dye for diagnosis of Barrett's esophagus is presently undergoing clinical evaluation. Current studies report good accuracy in predicting specialized intestinal metaplasia. To date, however, there is no definitive information on the inter- and intra-observer variability of these methods applied to the diagnosis of normal and dysplastic Barrett's mucosa.

MATERIAL AND METHODS

Sixty patients with endoscopically suspected Barrett's esophagus were investigated prospectively with the zoom endoscope after contrast enhancement of the mucosa with 1.5% acetic acid. Two hundred and twenty-three enlarged and histologically investigated areas of gastric, cardiac, normal and dysplastic Barrett's mucosa were photodocumented and in randomized sequence presented to 4 endoscopists in a blinded manner (2 with and 2 without experience of zoom endoscopy for evaluation). The reference for the first evaluation (A1) was standard endoscopic photographs of the respective, histologically confirmed mucosal entity. In a second evaluation (A2), the pictures were again interpreted by the same blinded investigators, but this time a modified pit-pattern classification as proposed by Sharma et al. was employed as the evaluation reference.

RESULTS

The diagnostic sensitivity for specialized intestinal metaplasia and dysplasia in Barrett's esophagus calculated for the A1 evaluation ranged -- investigator dependently -- from 54.9% to 80.7% and for A2 from 42.2% to 81.5%. The inter- and intra-observer variability for the evaluation procedure A1 and A2 was high (all kappa values <0.4). In particular, the inexperienced investigators demonstrated high intra-observer variability and low sensitivity in comparison with the experienced investigators.

CONCLUSIONS

The diagnosis of Barrett's mucosa using enhanced magnification endoscopy after acetic acid instillation is associated with a high level of interobserver variability. One reason is a frequent mismatch between cardiac mucosa and non-dysplastic Barrett's mucosa.

The endoscopic diagnosis and staging of oesophageal adenocarcinoma

The endoscopic evaluation of patients with oesophageal adenocarcinoma does not only serve the purpose of diagnosing the lesion and obtaining biopsies for histological evaluation: a systematic description of advanced lesions is also required to guide further therapeutic decisions. New endoscopic imaging modalities hold the promise of better endoscopic detection of early cancer and its precursor lesions in Barrett's oesophagus. Video-autofluorescence and narrow band imaging are the most promising techniques in this respect. The former may be used as a 'red flag' technique, identifying lesions that remain occult with white light endoscopy; the latter may be used as a targeted imaging technique, allowing for detailed inspection of the mucosal and vascular patterns that may help to distinguish early neoplasia from non-dysplastic tissue. Currently, prototypes are under investigation that combine high-resolution endoscopy, narrow band imaging and video-autofluorescence in one endoscopy system. Endoscopic ultrasonography (EUS) is superior to any other imaging modality in the assessment of local tumour infiltration of oesophageal adenocarcinoma and locoregional lymph nodes status. EUS allows for the identification of patients with advanced disease who are unlikely to benefit from attempts at curative surgery and in whom a conservative palliative treatment is indicated. EUS may also play a role in the selection of patients for local endoscopic treatment of early oesophageal cancer. EUS guided fine needle aspiration (EUS-FNA) of locoregional lymph nodes is safe with a high sensitivity and an impeccable specificity for assessment of malignant involvement. The indications for EUS-FNA of lymph nodes, however, depend on local treatment protocols: caeliac nodes (M1a) and lymph nodes located at or above the subcarinal area are the most widely used indications. In addition, it may be important if the choice for specific treatment protocols (e.g. neoadjuvant chemoradiotherapy) depends on lymph node status.

Preferred location for the development of esophageal adenocarcinoma within a segment of intestinal metaplasia

BACKGROUND

Barrett's metaplasia is the predominant precursor for the development of esophageal adenocarcinoma. This precancerous lesion has become the focus of various surveillance programs aimed at detecting earlier and therefore potentially curable lesions. However, sampling error by missing invasive cancer lesions is a common problem. This study aimed to identify preferred locations within a segment of Barrett's mucosa for the development of esophageal adenocarcinoma.

METHODS

The study group consisted of 213 patients with histologically proven esophageal adenocarcinoma. Of those, there were 134 cases of early cancer and 79 cases of locally advanced lesions. These patients received neoadjuvant chemotherapy. The frequency of intestinal metaplasia and the location of the tumor occurrence within the segment of intestinal metaplasia were assessed.

RESULTS

Intestinal metaplasia was found in 83% of the early lesions and in 98% of the advanced tumors after neoadjuvant chemotherapy. In 82.2% of the cases, the tumor was located at the distal margin of the intestinal metaplasia in patients with early tumor manifestations. The remaining tumor mass after neoadjuvant therapy also was located predominantly at the distal margin of the segment of intestinal metaplasia (85% of the cases).

CONCLUSIONS

The results demonstrate that almost all adenocarcinomas of the esophagus are based on the development of a segment of intestinal metaplasia. The distal margin of Barrett's mucosa seems to be the most vulnerable location for the development of invasive cancer.

Diagnostic and therapeutic endoscopy

Within the gastrointestinal tract, there is no shorter segment with a higher cancer incidence than the gastro-esophageal junction. Flexible endoscopy is the mainstay for diagnosis of early and advanced esophageal adenocarcinoma, for the treatment of early lesions, and also for the palliation of advanced cancer. New developments in endoscopy aim to improve the diagnosis and treatment of esophageal cancer. These include high resolution and magnification endoscopy in combination with chromendoscopy, and techniques based on modulation of the features of light bundles, such as narrow band imaging, fluorescence endoscopy, and elastic scattering spectroscopy. The value of these techniques for the surveillance of distal esophageal neoplasia needs further study. Furthermore, new methods of tissue sampling and evaluation are being studied to augment identification and staging of patients at risk for cancer. Finally, newer instruments may decrease patient burden during endoscopy, making screening and surveillance more acceptable from a patient's perspective. This review discusses the new developments in flexible endoscopy for diagnosis and therapy of early and advanced and advanced esophageal adenocarcinoma.

Barrett’s Esophagus: Diagnostic Approaches and Surveillance

In an effort to identify those patients at risk for developing esophageal adenocarcinoma, the American College of Gastroenterology recommends screening endoscopy in patients with chronic gastroesophageal reflux disease. Surveillance endoscopy is recommended every 3 years in those patients without dysplasia. For those patients with verified low-grade dysplasia, yearly surveillance endoscopy is recommended. In the case of high-grade dysplasia (HGD), either intensive endoscopic surveillance (focal HGD) or ablation/resection can be performed (multifocal HGD). Both observational and cost-effectiveness analyses suggest a potential benefit of endoscopic screening and surveillance, though these findings remain to be validated in controlled clinical trials. The development of new endoscopic imaging modalities may enhance the yield of biopsies obtained during screening and surveillance regimens.

Endoscopic treatment of high-grade intraepithelial neoplasia and early cancer in Barrett oesophagus

In the last 5 years, endoscopic therapy for high-grade intraepithelial neoplasia (HGIN) and early cancer (EC) in Barrett oesophagus has emerged as an effective and safe alternative to surgery. Adequate work-up of patients includes histopathological review of the initial biopsies, a high-resolution endoscopy with four-quadrant random biopsies every 1cm of Barrett mucosa and staging with endoscopic ultrasonography. Endoscopic resection (ER) forms the mainstay of the endoscopic treatment since it provides large tissue specimens for optimal histopathological evaluation. The ER-cap technique with submucosal injection and the 'suck-band-and cut' method are the resection methods most widely used in Barrett oesophagus patients. ER monotherapy for HGIN or EC in Barrett oesophagus is associated with recurrent lesions in up to 30% of treated patients. ER may be combined with ablative techniques such as photodynamic therapy (PDT) to treat all of the mucosa at risk for neoplastic progression. Unlike ER, PDT lacks histopathological correlation and residual Barrett mucosa may remain after treatment or may be hidden underneath the neosquamous epithelium. Management of Barrett oesophagus patients with HGIN or EC should be performed in centres with multi-disciplinary experience in this field and future studies should focus on development of ER techniques that allow radical resection of the whole Barrett segment.

Endoscopic detection of early upper GI cancers

The detection of early-stage neoplastic lesions in the upper GI tract is associated with improved survival and the potential for complete endoscopic resection that is minimally invasive and less morbid than surgery. Despite technological advances in standard white-light endoscopy, the ability of the endoscopist to reliably detect dysplastic and early cancerous changes in the upper GI tract remains limited. In conditions such as Barrett's oesophagus, practice guidelines recommend periodic endoscopic surveillance with multiple biopsies, a methodology that is hindered by random sampling error, inconsistent histopathological interpretation, and delay in diagnosis. Early detection may be enhanced by several promising diagnostic modalities such as chromoendoscopy, magnification endoscopy, and optical spectroscopic/imaging techniques, as these modalities offer the potential to identify in real-time lesions that are inconspicuous under conventional endoscopy. The combination of novel diagnostic techniques and local endoscopic therapies will provide the endoscopist with much needed tools that can considerably enhance the detection and management of early stage lesions in the upper GI tract.

Value of endoscopic methylene blue and Lugol's iodine double staining and detection of GST-Π and telomerase in the early diagnosis of esophageal carcinoma

AIM: To explore the expressions of GST-Π and telomerase activity in esophageal carcinoma and premalignant lesions and to investigate the value of endoscopic methylene blue (MB) and Lugol's iodine double staining.

METHODS: Seventy-two patients with esophagopathy were sprayed endoscopically with MB and Lugol's iodine in proper order and the areas stained blue and brown, and the area between the blue and brown stains were obtained. Depending on the pattern of mucosal staining, biopsy specimen was obtained. GST-Π and telomerase activity in specimens were examined by immunohis-tochemistry and PCR-based silver staining telomeric repeat amplification protocol, respectively.

RESULTS: After MB and Lugol's iodine staining, the area between both the colors was obtained in 64 of the 72 patients and the areas were stained blue and brown in all of the 72 patients. Association test of two simultaneous ordinal categorical data showed a correlation between the esophageal mucosal staining and the esophageal histology (P<0.005). The expression of GST-Π and telomerase activity in esophageal carcinoma and premalignant lesions increased. The expression of GST-Π and telomerase activity in dysplasia and carcinoma was significantly higher than that in normal epithelium (P<0.005). The expression in hyperplasia was slightly higher than that in normal epithelium. With the lesions progressing from low- to moderate- to high-grade dysplasia, the positive rate increased (P<0.025). Expression of GST-Π was correlated with that of telomerase activity in dysplasia and carcinoma (j = 0.4831, P<0.005; j = 0.3031, P<0.025, respectively); but there was no correlation between them in normal epithelium and hyperplasia.

CONCLUSION: The expression of GST-Π and telomerase may be an early event in the carcinogenesis of esophagus. They may play an induced and synergistic role with each other in the carcinogenesis of esophagus. Endoscopic MB and Lugol's iodine double staining and detection of GST-Π and telomerase activity may contribute to the early diagnosis of esophageal carcinoma.

Gastroesophageal reflux and cancer

The causal relationship between GERD and esophageal adenocarcinoma, although unclear just a few decades ago, now is established fairly well. The physiologic changes and the biocellular alterations of the damaged esophageal mucosa are documented better. Despite this knowledge, the dramatic increase in the incidence of esophageal cancer cannot be explained. The absolute risk of esophageal adenocarcinoma arising from GERD is low, and, at present, does not justify population-screening programs. Still, with the notion that adenocarcinoma of the esophagus is an aggressive cancer once documented, important questions still are in need of answers for patients suffering from reflux symptoms. Patients who have reflux disease are not necessarily symptomatic. It remains unclear if patients experiencing reflux symptoms should undergo mandatory endoscopy with biopsies at the esophagogastric junction. Furthermore, metaplasia of the lower esophagus often is not readily recognizable at endoscopy, and only biopsies can document abnormal histology. A severe and prolonged history of reflux always should orient to the possibility of a reflux-related columnar-lined esophagus. Once documented, Barrett's esophagus needs to be seen as a premalignant condition not necessarily leading to adenocarcinoma formation; despite their increased risk of tumor formation, most patients who have Barrett's esophagus die of other causes. During regular endoscopic follow-up, multilevel circumferential biopsies should document the evolution of the histologic changes in the lower esophagus and at the gastroesophageal junction of these patients. It is the only method available to document the appearance of dysplasia. It still is unclear if medicine or surgery provides the best quality of life and the best protection against the development of dysplasia and the possible progression toward adenocarcinoma formation when intestinal metaplasia is present in the esophagus.

Chromoendoscopy and magnifying endoscopy for Barrett's esophagus

Chromoendoscopy and magnification endoscopy are 2 endoscopic techniques used to improve visualization and diagnosis of gastrointestinal mucosa. This article summarizes the principles behind magnification endoscopy, with and without chromoendoscopy, for the diagnosis of Barrett's esophagus, dysplasia, and adenocarcinoma. Furthermore, this article discusses the possible clinical use of magnification endoscopy and chromoendoscopy in evaluating patients with chronic gastroesophageal reflux disease and Barrett's esophagus.

Is cytokeratin immunoreactivity useful in the diagnosis of short-segment Barrett's oesophagus in Korea?

BACKGROUND

Cytokeratin 7/20 staining has been reported to be helpful in diagnosing Barrett's oesophagus and gastric intestinal metaplasia. However, this is still a matter of some controversy.

OBJECTIVE

To determine the diagnostic usefulness of cytokeratin 7/20 immunostaining for short-segment Barrett's oesophagus in Korea.

METHODS

In patients with Barrett's oesophagus, diagnosed endoscopically, at least two biopsy specimens were taken from just below the squamocolumnar junction. If goblet cells were found histologically with alcian blue staining, cytokeratin 7/20 immunohistochemical stains were performed. Intestinal metaplasia at the cardia was diagnosed whenever biopsy specimens taken from within 2 cm below the oesophagogastric junction revealed intestinal metaplasia. Barrett's cytokeratin 7/20 pattern was defined as cytokeratin 20 positivity in only the superficial gland, combined with cytokeratin 7 positivity in both the superficial and deep glands.

RESULTS

Barrett's cytokeratin 7/20 pattern was observed in 28 out of 36 cases (77.8%) with short-segment Barrett's oesophagus, 11 out of 28 cases (39.3%) with intestinal metaplasia at the cardia, and nine out of 61 cases (14.8%) with gastric intestinal metaplasia. The sensitivity and specificity of Barrett's cytokeratin 7/20 pattern were 77.8 and 77.5%, respectively.

CONCLUSION

Barrett's cytokeratin 7/20 pattern can be a useful marker for the diagnosis of short-segment Barrett's oesophagus, although the false positive or false negative rate is approximately 25%.

Endoscopic treatment of high-grade dysplasia and early cancer in Barrett's oesophagus

Barrett's oesophagus is the premalignant precursor of oesophageal adenocarcinoma. Non-dysplastic metaplasia can progress to low-grade dysplasia, high-grade dysplasia, and finally to invasive cancer. Although the frequency of adenocarcinoma in patients with Barrett's oesophagus is low, surveillance is justified because the outcome of adenocarcinoma is poor. Oesophagectomy remains the standard treatment for patients with high-grade dysplasia and superficial carcinoma. However, it has been associated with substantial morbidity and mortality and some patients are judged unfit for surgery. In this review, the present status of less invasive procedures is discussed. Endotherapy preserves the integrity of the oesophagus and allows a better quality of life to patients at low risk of developing lymph-node metastases. Opposition to endoscopic treatment is based mainly on the identification of undetected foci of cancer and high-grade dysplasia in oesophagectomy samples. The current ablative techniques used are photodynamic therapy, argon plasma coagulation, laser treatment, and endoscopic mucosal resection.

A randomized crossover study comparing light-induced fluorescence endoscopy with standard videoendoscopy for the detection of early neoplasia in Barrett's esophagus

BACKGROUND

Light-induced fluorescence endoscopy (LIFE) may improve the detection of high-grade dysplasia (HGD) and early stage cancer (EC) in Barrett's esophagus (BE). The aim of this study was to compare LIFE with standard endoscopy (SE) in a randomized crossover study.

METHODS

Fifty patients with BE underwent SE and LIFE in a randomized sequence (4 to 6-week interval between procedures). The two procedures were performed by two different endoscopists who were blinded to the findings of the other examination. Targeted biopsy specimens were taken from detected lesions, followed by random biopsy specimens with a 2-cm interval, 4-quadrant protocol. Biopsy specimens were routinely evaluated and subsequently reviewed by a single, blinded expert GI pathologist.

RESULTS

Targeted biopsy specimens had a sensitivity for the diagnosis of HGD/EC of 62% (8/13) for both techniques. The overall sensitivity (all biopsy specimens) was 85% for SE and 69% for LIFE (p = 0.69). All targeted biopsy specimens had a positive predictive value (PPV) for HGD/EC of 41% for SE and 28% for LIFE (p = 0.40); autofluorescence-targeted biopsy specimens had a PPV of 13%. False-positive lesions had a significantly higher rate of acute inflammation than random biopsy specimens.

CONCLUSIONS

In this study, LIFE did not improve the detection of HGD or EC in patients with BE compared with SE.

Advances in Barrett's esophagus and esophageal adenocarcinoma

Despite advances in diagnosis and therapy, esophageal adenocarcinoma remains an aggressive and usually lethal tumor. This review focuses on the epidemiology of esophageal adenocarcinoma and its presumed precursor lesion, Barrett's esophagus; the pathogenesis of the cancer; advances in treatment of adenocarcinoma and Barrett's esophagus; and strategies for cancer prevention. Emphasis is placed on recent literature. Although the absolute number of cases of adenocarcinoma in the United States is still small, the incidence of this cancer has increased dramatically in the last 40 years, and adenocarcinoma is now the predominant form of esophageal cancer in this country. Recent evidence suggests that Barrett's esophagus is more prevalent in asymptomatic individuals than previously appreciated. The pathogenesis of Barrett's esophagus is poorly understood. Given that some subjects will have repeated bouts of severe erosive esophagitis and never develop Barrett's esophagus, host factors must play an important role. The utility of neoadjuvant radiation and chemotherapy in those with adenocarcinoma, although they are widely practiced, is not of clear benefit, and some authorities recommend against it. Ablative therapies, as well as endoscopic mucosal resection, hold promise for those with superficial cancer or high-grade dysplasia. Most series using these modalities feature relatively short follow-up, and longer-term data will be necessary to better describe the effects of these therapies. The value of chemoprevention in subjects with dysplastic Barrett's esophagus by use of cyclooxygenase 2 inhibitors, nonsteroidal anti-inflammatory drugs, or proton pump inhibitors is unknown. Similarly, although endoscopic screening is widely practiced, its value in patients with chronic gastroesophageal reflux disease symptoms is of unproven value, and recommending bodies are divided as to its practice.

Present status of photodynamic therapy for high-grade dysplasia in Barrett's esophagus

GOALS

Review recent developments in Barrett's dysplasia including regulatory approval of porfimer sodium photodynamic therapy.

BACKGROUND

Barrett's esophagus is thought to be the result of long-standing gastroesophageal reflux disease and is known to be the most important risk factor for the development of esophageal adenocarcinoma. The natural history of Barrett's esophagus is not well known, but the annual incidence of invasive adenocarcinoma is estimated to be 0.5% (reported range, 0.2%-2.0%). This represents an increased risk for esophageal cancer of 30 to 60 times higher than normal subjects. As for colorectal cancer, malignant degeneration is Barrett's esophagus is thought to occur through a continuum of histologic stages: metaplasia, dysplasia and neoplasia. Barrett's high-grade dysplasia (formerly referred to as carcinoma in situ) is the histologic stage of disease that immediately precedes the development of invasive carcinoma.

CONCLUSIONS

Previously, Barrett's high-grade dysplasia patients were routinely referred for esophageal resection surgery based upon the assumption of inevitable progression to cancer, the high rate of undiagnosed synchronous cancers, and few treatment alternatives. Important developments in Barrett's high-grade dysplasia include recent publications regarding the natural history of Barrett's high-grade dysplasia and the regulatory approval for endoscopic ablation therapy using porfimer sodium photodynamic therapy (Photofrin PDT).

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.

Prevention and management of early esophageal cancer

Early esophageal cancer is defined by its limitation to the esophageal mucosa and submucosa. It has become a curable malignant disease, in sharp contrast to the dismal prognosis of esophageal cancer at advanced stages, which still represents the majority of patients. Understanding the risk factors, establishing surveillance programs for patients at risk, and developing preventative interventions such as dietary and lifestyle changes or pharmacologic interventions hold the potential of reducing the incidence of the disease and of shifting the stage distribution toward early cancer. Endoscopic ultrasound examination is pivotal for distinguishing early from advanced stages of the disease because it allows for accurate assessment of tumor infiltration and regional lymph node involvement. The therapeutic mainstay for early esophageal cancer remains surgery. New, less invasive surgical techniques are being tested that are associated with less morbidity and mortality than standard radical esophagectomies. For patients who are not candidates for surgery, definitive chemoradiation is a viable alternative. New endoscopic ablation techniques, such as endoscopic mucosa resection and photodynamic therapy, are potential alternatives to surgery in patients with cancers limited to the mucosa. For patients with adenocarcinoma of the gastroesophageal junction with submucosal involvement, adjuvant chemoradiation should be considered because of its potential to increase survival.

Advanced esophageal cancer

Although the prognosis for patients with early cancer is good, throughout the world the majority of patients present with advanced disease, and in them, survival is poor. Accurate staging is essential to inform prognosis; to select candidates who may be cured by surgery alone; to select patients requiring neoadjuvant therapy, especially when new protocols are being studied; and to detect patients with advanced disease who would be best served by palliative therapy.

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Prediction of appropriateness of local endoscopic treatment for high-grade dysplasia and early adenocarcinoma by EUS and histopathologic features

BACKGROUND

Endoscopic techniques are being developed for the local treatment of early stage esophageal cancer. However, such therapy is not appropriate for patients with lymph node metastasis. The aim of this study was to analyze the histopathologic features of high-grade dysplasia and early stage adenocarcinoma and to relate these to lymph node involvement.

METHODS

Pathology reports were reviewed for all 367 patients who underwent subtotal esophagectomy for high-grade dysplasia or adenocarcinoma of the esophagus or the gastroesophageal junction between January 1993 and December 2001. Patients with histopathologically confirmed high-grade dysplasia or T1 carcinoma were included (n = 77). Pre-operative EUS results were assessed. All lesions were histopathologically subdivided in 6 different stages (mucosal 1-3 and submucosal 1-3).

RESULTS

EUS staged 61 patients as N0. EUS correctly predicted the absence of positive lymph nodes in 57 (93%) of these patients. Histopathologically, m1, m2, m3, and sm1 cancers never had lymph node metastases, whereas 3 of 13 sm2 tumors (23%) and 9 of 13 sm3 tumors (69%) had lymph node involvement. Lymphangio invasion was present exclusively in sm2 and sm3 cancers. Factors that predicted the presence of lymph node metastasis were the following: tumor diameter greater than 3 cm, infiltration of malignancy beyond sm1, poor differentiation grade, and lymphangio invasion, although only infiltration beyond sm1 remained significant in the definitive multivariate analysis.

CONCLUSIONS

EUS and the histopathologic features of high-grade dysplasia and early stage adenocarcinoma of the esophagus or the gastroesophageal junction can predict the presence of lymph node involvement. These data can be used to identify patients for whom local endoscopic treatment may be appropriate.

Chromoendoscopy and magnification endoscopy for diagnosing esophageal cancer and dysplasia

Based on preliminary reports, the use of chromoendoscopy and magnification endoscopy appears to be a valuable adjunct to standard endoscopy for the detection and classification of metaplastic and dysplastic lesions of the esophagus. Ideally, the use of this technique would enable the endoscopist to rule in or out the presence of intestinal metaplasia and dysplastic/cancerous epithelium by obtaining only a minimal number of targeted biopsy specimens--or potentially taking no biopsies at all, which could transform upper endoscopy into a much more effective screening and surveillance tool. There are several problems with the use of chromoendoscopy and magnification endoscopy in the esophagus. This technique is operator-dependent (ie, dependent on the skill and experience of the endoscopist). Studies reporting the accuracy of chromoendoscopy remain mixed, especially for Barrett's esophagus and dysplasia, which is likely explained by differences in techniques and materials used in the investigations. Staining within the esophagus is often patchy and uneven. Poor spraying technique can exaggerate irregular uptake by the mucosa. There is a high false-positive rate when staining gastric-type epithelium or in the setting of inflammation. Areas of dysplasia or cancer might take up stain in an irregular manner or might not stain at all. Magnification only allows the endoscopist to observe small areas of mucosa at a time, increasing the overall difficulty of the procedure and procedure length. Currently, the greatest body of literature exists concerning the use of Lugol's solution for the diagnosis of squamous cell dysplasia/carcinoma of the esophagus and methylene blue for diagnosing Barrett's esophagus. If used consistently by practicing physicians, the accuracy of biopsies could be improved. If endoscopic ablative therapy for high-grade dysplasia and early carcinoma (eg, photodynamic therapy and endoscopic mucosal resection) becomes accepted, sensitive methods of detecting residual metaplastic or dysplastic epithelium after ablation will be needed to help guide additional endoscopic therapy. Chromoendoscopy and magnification endoscopy could prove helpful in this setting. Further research in this field needs to be performed. As a first step, a uniform classification system for staining and magnification patterns should be devised. Future studies could then be performed using consistent terminologies. More controlled investigations with larger numbers of patients must be performed before tissue staining and magnification endoscopy become a part of day-to-day endoscopic practice. Lugol's chromoendoscopy is a simple technique for the detection of synchronous squamous dysplasia and cancer, but a substantial amount of work remains to be performed for the validation of chromoendoscopy for the detection of Barrett's esophagus and dysplasia. The ultimate aim of chromoendoscopy and magnification endoscopy in the esophagus is to show improved outcomes (ie, early detection of cancer and improved survival). These goals have not yet been realized and will require welldesigned studies in the future.

Review article: emerging techniques for screening and surveillance in Barrett's oesophagus

The incidence of oesophageal adenocarcinoma continues to increase in the US and the Western world, with the 5-year survival rate for this cancer still being very dismal. The diagnosis of Barrett's metaplasia and dysplasia (i.e. screening and surveillance) currently requires endoscopy with biopsy of the abnormally appearing distal oesophagus. Surveillance endoscopy in patients with Barrett's oesophagus relies on the performance of random biopsies from the metaplastic segment, with the aim of identifying dysplasia and/or cancer. However, intestinal metaplasia and dysplasia are not uniformly distributed within the columnar-lined mucosa in the distal oesophagus, and the sensitivity of standard endoscopy with biopsy for the detection of these lesions is low. New techniques to improve the accuracy of endoscopic diagnosis, as well as to identify patients at high risk for neoplasia development, have recently been developed and most are currently being evaluated in clinical studies. The results with these techniques, although promising, are still preliminary. They hold promise for the improved detection of dysplasia and neoplasia at an early stage of development, with a greater chance for early treatment, and therefore a greater likelihood of either cure of adenocarcinoma or prevention of its development from dysplasia.

A critical review of the diagnosis and management of Barrett's esophagus: the AGA Chicago Workshop

BACKGROUND & AIMS

The diagnosis and management of Barrett's esophagus (BE) are controversial. We conducted a critical review of the literature in BE to provide guidance on clinically relevant issues.

METHODS

A multidisciplinary group of 18 participants evaluated the strength and the grade of evidence for 42 statements pertaining to the diagnosis, screening, surveillance, and treatment of BE. Each member anonymously voted to accept or reject statements based on the strength of evidence and his own expert opinion.

RESULTS

There was strong consensus on most statements for acceptance or rejection. Members rejected statements that screening for BE has been shown to improve mortality from adenocarcinoma or to be cost-effective. Contrary to published clinical guidelines, they did not feel that screening should be recommended for adults over age 50, regardless of age or duration of heartburn. Members were divided on whether surveillance prolongs survival, although the majority agreed that it detects curable neoplasia and can be cost-effective in selected patients. The majority did not feel that acid-reduction therapy reduces the risk of esophageal adenocarcinoma but did agree that nonsteroidal antiinflammatory drugs are associated with a cancer risk reduction and are of promising (but unproven) value. Participants rejected the notion that mucosal ablation with acid suppression prevents adenocarcinoma in BE but agreed that this may be an appropriate strategy in a subgroup of patients with high-grade dysplasia.

CONCLUSIONS

Based on this review of BE, the opinions of workshop members on issues pertaining to screening and surveillance are at variance with published clinical guidelines.

Cardia-type metaplasia arising in the remnant esophagus after cardia resection

BACKGROUND

Specialized intestinalized metaplasia in the distal esophagus (Barrett's esophagus) is a recognized precursor of esophageal adenocarcinoma, but its pathogenesis is incompletely understood. The aim of this study was to investigate the mucosal effects of esophagogastrostomy, an artificial interface between esophageal squamous and gastric oxyntic epithelium.

METHODS

EGD was performed in 14 consecutive patients (median age 63 years, range 26-71 years) who had undergone esophagogastrostomy from 3 to 88 months earlier. Biopsy specimens were obtained in 13 patients from the anastomosis and, when present, columnar epithelium in the remnant esophagus.

RESULTS

In 10 patients, EGD demonstrated tongue-shaped segments of columnar epithelium extending from 0.3 to 7 cm into the remnant esophagus. Biopsy specimens revealed cardia-type mucosa in all patients, whether at the anastomosis or proximally in esophageal segments of columnar epithelium. Magnification endoscopy of cardia-type mucosa visualized a long-oval, tubular, or ridged surface pattern. In 3 cases, complete intestinal metaplasia was observed within the cardia-type mucosa.

CONCLUSIONS

The frequent transformation of squamous epithelium into cardia-type mucosa in the distal remnant esophagus after esophagogastrostomy supports the concept that cardia-type mucosa is a reflux-induced metaplasia that may give rise to the subsequent development of specialized intestinalized metaplasia.

Detection of intestinal metaplasia in distal esophagus and esophagogastric junction by enhanced-magnification endoscopy

BACKGROUND

Standard videoendoscopy identifies columnar-lined esophagus but cannot distinguish intestinal metaplasia from other types of epithelium. Enhanced-magnification endoscopy identifies different mucosal pit patterns. A preliminary study suggested that a type 3 pattern is associated with the presence of intestinal metaplasia. This study assesses the value of enhanced-magnification endoscopy for the detection of intestinal metaplasia in the distal esophagus and esophagogastric junction in patients undergoing diagnostic EGD.

METHODS

Patients undergoing diagnostic endoscopy for upper-GI symptoms underwent enhanced-magnification endoscopy after instillation of 1.5% acetic acid. The enhanced-magnification endoscopy mucosal pattern was classified into 3 types: 1, normal pits; 2, slit-reticular pattern; and 3, gyrus-villous pattern. Preliminary studies indicated that the type 3 pattern was related to intestinal metaplasia. One to 6 biopsies were targeted to areas having a type 3 pattern in columnar-appearing mucosa in the distal esophagus or esophagogastric junction. In the absence of type 3 pattern, one to 8 biopsies were targeted to areas with a type 2 pattern in columnar-appearing mucosa in the distal esophagus or esophagogastric junction.

RESULTS

The overall frequency of intestinal metaplasia in the esophagus and esophagogastric junction was 38.8% (26/67 patients). There was a good correlation between the type 3 pattern and intestinal metaplasia in targeted biopsy specimens (sensitivity 88.5%, specificity 90.2%, positive predictive value 85.2%, negative predictive value 92.5%, overall accuracy 90.0%).

CONCLUSIONS

Enhanced-magnification endoscopy is useful for detection of intestinal metaplasia in distal esophagus and esophagogastric junction.

Screening for Barrett's esophagus in colonoscopy patients with and without heartburn

BACKGROUND & AIMS

The population prevalence of Barrett's esophagus (BE) is uncertain. Our aim was to describe the prevalence of BE in a volunteer population.

METHODS

Upper endoscopy (EGD) was performed in 961 persons with no prior history of EGD who were scheduled for colonoscopy. Symptom questionnaires were completed prior to endoscopy. Biopsy specimens were taken from the gastric cardia and any columnar mucosa extending > or =5 mm into the tubular esophagus and from the stomach for H. pylori infection in the last 812 patients.

RESULTS

The study sample was biased toward persons undergoing colonoscopy, males, and persons with upper GI symptoms. The prevalence of BE was 65 of 961 (6.8%) patients, including 12 (1.2%) with long-segment BE (LSBE). Among 556 subjects who had never had heartburn, the prevalences of BE and LSBE were 5.6% and 0.36%, respectively. Among 384 subjects with a history of any heartburn, the prevalences of BE and LSBE were 8.3% and 2.6%, respectively. In a univariate analysis, LSBE was more common in those with any heartburn vs. those with no heartburn (P = 0.01), but the sample size was insufficient to allow multivariate analysis of predictors of LSBE. In a multivariate analysis, BE was associated with increasing age (P = 0.02), white race (P = 0.03), and negative H. pylori status (P = 0.04). Overall, BE was not associated with heartburn, although heartburn was more common in persons with LSBE or circumferential short segments.

CONCLUSIONS

LSBE is very uncommon in patients who have no history of heartburn. SSBE is relatively common in persons age > or =40 years with no prior endoscopy, irrespective of heartburn history.

Cromoendoscopia com azul de metileno para diagnóstico de esôfago de Barrett

RACIONAL: O esôfago de Barrett é uma condição na qual a mucosa escamosa esofágica é substituída por metaplasia intestinal especializada, que predispõe o paciente ao desenvolvimento de adenocarcinoma esofágico. Este é precedido por displasia e carcinoma precoce; o rastreamento dessas lesões faz-se através de endoscopias digestivas periódicas com biopsias randomizadas. A incidência aumentada desse, tem despertado interesse no desenvolvimento de novas técnicas endoscópicas, como a cromoendoscopia com azul de metileno, para melhorar a identificação do esôfago de Barrett e suas complicações. OBJETIVO: Determinar se as biopsias dirigidas pela cromoendoscopia com azul de metileno oferecem vantagem em relação ao método convencional na detecção do esôfago de Barrett. MATERIAL E MÉTODO: Estudaram-se 45 pacientes com diagnóstico prévio de esôfago de Barrett, todos submetidos a dois exames de endoscopia digestiva alta com biopsias, em intervalo de 4 semanas, um convencional e outro com aplicação do corante, no período entre abril e outubro de 2002. RESULTADOS: Os resultados histológicos das biopsias de todos os exames foram comparados. Observou-se sensibilidade de 62,5%, especificidade de 15,4%, valor preditivo positivo de 57,7% e valor preditivo negativo de 18,2%. Não houve diferença significativa quanto ao número de biopsias. O tempo de duração da técnica de cromoendoscopia foi significativamente maior quando comparado ao da técnica convencional. CONCLUSÃO: Não se observou vantagem na utilização da cromoendoscopia em relação à técnica randomizada no diagnóstico do esôfago de Barrett.

Follow-up for high-grade dysplasia in Barrett's esophagus

This article will focus on the value of endoscopic follow-up for patients with high-grade dysplasia (HGD). Because the diagnosis of HGD in Barrett's esophagus is not a simple straightforward task, the article first will discuss the controversies regarding the histological diagnosis, followed by a discussion of the importance of endoscopic imaging for making the clinical diagnosis of HGD, and a systematic review of the literature relating to the presence of synchronous cancers in patients with HGD and the occurrence of cancer during endoscopic follow-up in these patients (metachronous cancers). Furthermore, the article will also discuss endoscopic techniques currently available for surveillance of these patients and make recommendations regarding surveillance intervals and the optimal biopsy protocol.

Barrett esophagus: endoscopic findings and what to biopsy

Barrett esophagus (BE) is considered the precursor for nearly all cases of esophageal adenocarcinoma. The potential sequence from intestinal metaplasia to dysplasia to cancer can best be monitored by careful endoscopic observation and surveillance biopsies. The ability to diagnose BE, biopsy accurately, and appropriately monitor are requisites for all who care for patients with this disorder. The normal endoscopic anatomy of the esophagogastric junction region and the changes that are associated with BE are discussed. The relationship of the squamocolumnar mucosal junction to the proximal margin of the gastric folds and the distal extent of the linear esophageal vessels is the principal landmark for diagnosis. Chromoendoscopy with methylene blue and Lugol iodine will enhance endoscopic observation, thereby allowing directed biopsies. Biopsy forceps and technique are reviewed along with the when and where for surveillance biopsies. Since most dysplasia and intramucosal cancer is focal and invisible to the endoscopist, it is easy to understand why the sampling error exceeds 95% using a standard four-quadrant biopsy protocol. Currently, this sampling error can be reduced by four-quadrant biopsies at closer intervals and biopsies of even the most minor focal abnormalities of mucosa in the BE segment. Screening may be enhanced in the future depending upon successful development of new cytologic, spectrographic, and tomographic methods capable of identifying foci of dysplasia or cancer that can be confirmed by targeted biopsies.

Magnification chromoendoscopy for the diagnosis of gastric intestinal metaplasia and dysplasia

BACKGROUND

The aim of this study was to define the reproducibility and accuracy of magnification chromoendoscopy for the diagnosis of lesions associated with gastric cancer (intestinal metaplasia and dysplasia).

METHODS

A total of 136 patients with previously diagnosed lesions and 5 gastrectomy specimens were studied. Endoscopic examination was performed with a magnification endoscope after methylene blue (1%) spraying. According to differences in color and mucosal pattern, groups and subgroups of endoscopic images were defined, and biopsies taken (n = 462). Five endoscopists were asked to classify individually 2 endoscopic images per subgroup on 2 separate occasions.

RESULTS

Three groups of endoscopic images were defined: nonmetaplastic, nondysplastic mucosa (I); metaplastic mucosa (II); and dysplastic mucosa (III). Ten subgroups were defined according to pit pattern: round small (IA), round and tubular small (IB), coarse round (IC), and course round pits with a straight pit (ID); blue irregular marks (IIA), blue round and tubular pits (IIB), blue villi (IIC), and blue small pits (IID); and loss of clear pattern, with depression (IIIA) or with slight elevation (IIIB). The kappa statistic for intraobserver agreement on the classification of endoscopic images in groups was 0.86; for interobserver agreement, it was 0.74. For classification into subgroups, kappa values ranged from 0.48 to 0.78. For 85% of the areas classified endoscopically as Group I (n = 146), no mucosal lesions or gastritis was described at histologic examination; for 83% of those in Group II (n = 198), intestinal metaplasia was found. Subgroups IIA and IIB were more often associated with complete intestinal metaplasia (62%), and IIC and IID with incomplete metaplasia (67%); in Group III (n = 118), dysplasia was diagnosed histopathologically in 33%. For the diagnosis of dysplasia, specificity was 81% (95% CI [77%, 85%]) and negative predictive value 99% (95% CI [99%, 100%]).

CONCLUSIONS

Gastric endoscopic patterns with chromoendoscopy and magnification seem reproducible and valid for the diagnosis of lesions associated with gastric cancer. This procedure may improve the follow-up of individuals at high-risk of gastric cancer, at least for the exclusion of severe lesions.

Does methylene blue detect intestinal metaplasia in Barrett's esophagus?

BACKGROUND

Methylene blue has been used to selectively stain areas of specialized intestinal metaplasia in Barrett's esophagus. The sensitivity, specificity, and negative and positive predictive values for the detection of specialized intestinal metaplasia by methylene blue chromoendoscopy were determined in patients with Barrett's esophagus.

METHODS

Thirty patients with Barrett's esophagus underwent endoscopy with biopsy specimens obtained from areas that stained positive and negative with methylene blue. Histopathologic findings were compared with methylene blue chromoendoscopy findings.

RESULTS

Two hundred ninety-two biopsy specimens (mean 9.7/patient) were obtained: 203 from stained and 89 from unstained areas. Sensitivity, specificity, and negative and positive predictive values for detection of specialized intestinal metaplasia were, respectively, 72%, 46%, 22%, and 89%. Comparing 187 biopsy specimens from patients with long-segment Barrett's esophagus with 105 specimens from patients with short-segment Barrett's esophagus, the sensitivity, specificity, and negative and positive predictive values were, respectively, 77% versus 63% (p = 0.044), 79% versus 21% (p < 0.002), 28% versus 14% (p = 0.219), and 97% versus 73% (p < 0.002). The odds ratio for detection of specialized intestinal metaplasia in stained areas was 12.40 in long-segment and 0.45 in short-segment Barrett's esophagus.

CONCLUSIONS

Data from this study confirm the value of methylene blue chromoendoscopy for detection of specialized intestinal metaplasia in long-segment Barrett's esophagus, but not in short-segment Barrett's esophagus.

Chromoendoscopy and magnification endoscopy in Barrett's esophagus

Chromoendoscopy and magnification endoscopy appear to be a valuable adjuncts for the detection and classification of BE. These techniques may also prove to be useful aids in surveillance protocols for identifying dysplastic epithelium or early cancer within a segment of BE. Ideally, the use of these techniques would enable the endoscopist to rule in or out the presence of IM and of dysplastic or cancerous epithelium by obtaining only a minimal number of targeted biopsy specimens, or potentially performing no biopsies at all. This could transform upper endoscopy into a much more effective screening and surveillance tool for BE. Several problems currently exist for the use of chromoendoscopy for BE. Results of studies reporting the accuracy of chromoendoscopy remain mixed,and are likely explained by the wide range of techniques and materials used in the investigations. Staining adds several steps, and likely several minutes, to an upper endoscopy. Staining within the esophagus is often patchy and uneven. In addition, poor spraying technique exaggerates the irregular uptake by the mucosa. There is a high false-positive rate when staining gastric-type epithelium and denuded epithelium. Areas of dysplasia or cancer may take up stain in an irregular manner, or may not stain at all. Chromoendoscopy is a relatively new technique in the management of BE and depends on the skill and experience of the endoscopist. Magnification, however, only allows the endoscopist to observe small areas of mucosa at a time, increasing the overall complexity and length of the procedure. The learning curve for this procedure is relatively short, however, and endoscopists can usually become proficient in the technique quickly. Currently, the greatest body of literature exists concerning the use of methylene blue for diagnosing BE. At the present time, chromoendoscopy and magnification endoscopy appear to be most beneficial in detecting IM in short segments of esophageal columnar-appearing mucosa. If used consistently by practicing physicians, the accuracy of biopsies for IM could be improved. If endoscopic ablative therapy for HGD and early adenocarcinoma becomes accepted, sensitive methods of detecting residual BE after ablation will be needed to help guide additional endoscopic therapy. Chromoendoscopy and magnification endoscopy could prove helpful in this setting. Further research in this field remains to be performed. As a first step, a uniform classification system for staining and magnification patterns should be devised. If investigators can reach a consensus, and validate classification, terminology, and pattern-types, future studies could be performed using "common and similar language." More controlled investigations with larger numbers of patients must be performed before tissue staining and magnification endoscopy become a part of the practicing endoscopist's armamentarium. The ultimate aims of chromoendoscopy and magnification endoscopy in the setting of BE are to show improved outcomes--namely, early detection of cancer and improved survival rates. These goals have not yet been realized and meeting them will require well-designed studies in the future.

Magnification chromoendoscopy for the detection of intestinal metaplasia and dysplasia in Barrett's oesophagus

BACKGROUND

The presence of intestinal metaplasia (IM) in the columnar lined distal oesophagus defines Barrett's oesophagus with the risk of future malignant transformation. The distribution of both IM and dysplasia (low grade (LGD) and high grade (HGD)) within the columnar lined oesophagus is patchy and mosaic requiring random biopsies. Techniques that could help target areas of high yield within Barrett's mucosa would be helpful.

AIM

To study the utility of high magnification chromoendoscopy (MCE) in the detection of IM, LGD, and HGD in patients with Barrett's oesophagus.

METHODS

Consecutive patients detected with columnar mucosa in the distal oesophagus were studied using an Olympus magnification endoscope (GIF-Q16OZ, 115x). The distal oesophagus was sprayed with indigo carmine solution and the oesophageal columnar mucosa patterns were noted under high magnification and targeted for biopsy. All biopsies were read by pathologists blinded to the endoscopic findings.

RESULTS

Eighty patients with suspected Barrett's oesophagus (that is, columnar lined distal oesophagus) were studied: mean age 62.7 years (range 35-81). Mean length of columnar mucosa was 3.7 cm (range 0.5-17). Three types of mucosal patterns were noted within the columnar mucosa after spraying indigo carmine and using MCE: ridged/villous pattern, circular pattern, and irregular/distorted pattern. The yield of IM on target biopsies according to the patterns was: ridged/villous 57/62 (97%) and circular 2/12 (17%). Six patients had an irregular/distorted pattern and all had HGD on biopsy (6/6 (100%)). Eighteen patients had LGD on target biopsies; all had the ridged/villous pattern. All patients with long segment Barrett's were identified using MCE whereas 23/28 patients (82%) with short segment Barrett's had the ridged/villous pattern.

CONCLUSIONS

MCE helps visually identify areas with IM and HGD having specific patterns but not patients with LGD (appear similar to IM). MCE may be a useful clinical tool for the increased detection of patients with IM as well as for surveillance of patients for the detection of HGD. If these preliminary results are validated, MCE would help identify high yield areas, potentially eliminating the need for random biopsies.

Endoscopically observed lower esophageal capillary patterns

BACKGROUND

It has been reported that there are four zones of distinct venous patterns around the gastroesophageal junction (GEJ); i.e. truncal, perforating, palisade (PZ) and gastric zones. Using the distal end of PZ as a marker for GEJ, this study was done to assess the length and patterns of PZ in Koreans, and to assess the prevalence of endoscopic Barrett's esophagus (E-BE) and hiatal hernia (E-HH).

METHODS

847 consecutive patients undergoing diagnostic endoscopy were included. During endoscopy, PZ, squamocolumnar junction (SCJ) and pinchcock action (PCA) were identified. Patterns were classified according to the relationships of the distal end of PZ with SCJ and PCA; A: all three at the same level, B: SCJ proximal to the other two which are at the same level, C: PCA distal to the other two which are at the same level, D: SCJ proximal to the distal end of PZ which is proximal to PCA. Cases with patterns B and D were thought to have E-BE, and those with patterns C and D to have E-HH.

RESULTS

Patterns A, B, C and D were 79.2%, 12.1%, 3.8% and 4.9%, respectively. Length of PZ was 3.0 +/- 0.1 cm. E-BE and E-HH were found in 17.0% and 8.7%, respectively. Both E-BE and E-HH were more frequently found in males and in cases with reflux esophagitis.

CONCLUSION

E-BE and E-HH are not so infrequent in Koreans as previously thought, if we use the distal end of PZ as an endoscopic marker of GEJ.

Barrett's esophagus and esophageal adenocarcinoma: pathogenesis, diagnosis, and therapy

Gastric juice that refluxes into the esophagus can injure esophageal squamous epithelium. When the injury heals through a metaplastic process in which an abnormal columnar epithelium replaces the injured squamous one, the resulting condition is called Barrett's esophagus. Gastroesophageal reflux disease and Barrett's esophagus are the most important risk factors for esophageal adenocarcinoma. This article examines such issues as the treatment, endoscopic surveillance, and chemoprevention of Barrett's esophagus. Also included are published guidelines and recommendations.

Barrett's esophagus

Barrett's esophagus is an acquired condition resulting from severe esophageal mucosal injury. It still remains unclear why some patients with gastroesophageal reflux disease develop Barrett's esophagus whereas others do not. The diagnosis of Barrett's esophagus is established if the squamocolumnar junction is displaced proximal to the gastroesophageal junction and if intestinal metaplasia is detected by biopsy. Despite this seemingly simple definition, diagnostic inconsistencies remain a problem, especially in distinguishing short segment Barrett's esophagus from intestinal metaplasia of the gastric cardia. Barrett's esophagus would be of little importance were it not for its well-recognized association with adenocarcinoma of the esophagus. The incidence of esophageal adenocarcinoma continues to increase and the 5-year survival rate for this cancer remains dismal. However, cancer risk for a given patient with Barrett's esophagus is lower than previously estimated. Current strategies for improved survival in patients with esophageal adenocarcinoma focus on cancer detection at an early and potentially curable stage. This can be accomplished either by screening more patients for Barrett's esophagus or with endoscopic surveillance of patients with known Barrett's esophagus. Current screening and surveillance strategies are inherently expensive and inefficient. New techniques to improve the efficiency of cancer surveillance are evolving rapidly and hold the promise to change clinical practice in the future. Treatment options include aggressive acid suppression, antireflux surgery, chemoprevention, and ablation therapy, but there is still no clear consensus on the optimal treatment for these patients.

Interventional endoscopy in the diagnosis and staging of upper gastrointestinal malignancy

Increased population longevity as well as an emphasis on earlier diagnosis and more effective treatment of cancer have created an environment for new technologies and techniques to flourish. Some of the endoscopic entities discussed in this article have not been fully validated in clinical practice. Innovative spectroscopic modalities hold a great deal of promise, but are years away from general applicability. In contrast, many interventional endoscopic techniques are currently available and confer heightened levels of diagnostic and staging accuracy for gastric and esophageal malignancies. Earlier diagnosis can identify patients who may be eligible for less-invasive treatment options such as EMR. Minimally invasive treatment options and maximum staging accuracy are more important for patients who are marginal surgical candidates and for accurate comparison of clinical trials studying treatment options. Our challenge for the future is to properly integrate these technologic advances with the science of good medical practice.