Mucosectomy for high‐grade dysplasia in Barrett's esophagus

Reports on the natural history of high‐grade dysplasia (HGD) are sometimes contradictory, but suggest that 10–30% of patients with HGD in Barrett's esophagus (BE) will develop a demonstrable malignancy within five years of the initial diagnosis. Surgery has to be considered the best treatment for HGD or superficial carcinoma, but is contraindicated in patients with severe comorbidities. Non‐surgical treatments such as intensive endoscopic surveillance, endoscopic ablative therapies, and endoscopic mucosal resection (EMR) have been proposed. EMR is a newly developed procedure promising to become a safe and reliable non‐operative option for the endoscopic removal of HGD or early cancer within BE. It is important to assess the depth of invasion of the lesion and lymph node involvement before choosing EMR. This technique permits more effective staging of disease obtaining a large sample leading to a precise assessment of the depth of malignant invasion. Complications such as bleeding and perforation may occur, but can be treated endoscopically. Trials are needed to compare endoscopic therapy with surgical resection to establish clear criteria for EMR and ablative therapies.     

Barrett's esophagus

Esophageal cancer staging is a widely accepted indication for endoscopic ultrasonography (EUS). The evaluation of Barrett's esophagus (BE) with EUS is indicated only when there is high-grade dysplasia or a concern for malignancy in an endoscopic lesion. Because the options for the management of BE and early adenocarcinoma are diverse, proper selection of patients by accurate staging with EUS is critical, particularly when nonoperative management is considered. For example, patients with BE with high-grade dysplasia may be offered esophagectomy in some medical centers, but nonoperative therapies such as endoscopic ablative therapy or mucosal resection may be the preferred treatment options in other gastroenterology practices. This article discusses the scientific evidence for the use of EUS in BE or early esophageal adenocarcinoma.     

黏膜切除治疗Barrett食管疗效及安全性的Meta分析

目的评价黏膜切除(EMR)对于Barrett食管(BE)治疗的有效性、持久性及不良事件发生率。方法计算机检索Embase、PubMed、维普、中国期刊全文数据库、万方数字化期刊全文数据库等。提取各病理类型的BE接受EMR治疗后根除肠上皮化生(CE-IM)、上皮内瘤变(CE-N)的比率,治疗随访期间肠上皮化(IM)或瘤变复发及不良事件发生率,应用R3.1.3软件合并数据进行统计学分析,计算其有效性、持久性及不良事件发生率。结果共纳入4篇研究,总病例130例。EMR治疗异型增生或黏膜内癌的BE患者中,达到CE-N为97%(95%CI:0.91~0.99),达到CE-IM为91%(95%CI:0.83~0.95),在随访过程中瘤变或IM复发率为8%,常见并发症食管狭窄与出血,其发生率分别为39%和6%。结论 EMR作为BE内镜治疗的推荐方式,其在治疗伴异型增生或黏膜内癌的BE上有确切的效果,但其并发症特别是食管狭窄发生率较高。     

The role of endoscopic ultrasound in the diagnosis and management of Barrett's esophagus

Although initial studies suggest a limited role for EUS in the detection of BE and the diagnosis and staging of dysplasia, a defined role in several specific situations is emerging. EUS is useful in selecting appropriate candidates for nonoperative therapies by excluding patients with submucosal cancers and those with malignant lymph nodes. EUS may also help in the selection of patients for EMR, either alone or in combination with ablative therapies.     

Diagnosis and management of Barrett's esophagus: What's next?

The past decade has led to marked improvements in our understanding regarding the pathogenesis and risk of progression of Barrett's esophagus (BE), enhanced imaging technology to improve dysplasia detection, and the development and refinement of endoscopic techniques, such as mucosal ablation and endoscopic mucosal resection(EMR), to eradicate BE. However, many questions remain including identifying which, if any, candidates are most appropriate for screening for BE; how to improve current surveillance protocols; predicting which patients with BE will develop neoplastic progression; identifying the most appropriate candidates for endoscopic eradication therapy; developing algorithms for appropriate management posteradication; and understanding the potential role of chemoprophylaxis. This article describes potential future advances regarding screening, surveillance, risk stratification, endoscopic eradication therapies, and chemoprevention and provides a potential future management strategy for patients with BE.     

Lifting of lesions during endoscopic mucosal resection (EMR) of early colorectal cancer: implications for the assessment of resectability

BACKGROUND AND STUDY AIMS: This study assessed the indications for and limitations of endoscopic mucosal resection (EMR) for early colorectal cancer, focusing on the way in which the lesion lifts after submucosal injection. PATIENTS AND METHODS: The study included 94 patients with early colorectal cancer who received EMR treatment. The lifting of the lesion after submucosal injection was analyzed (classified as completely lifted/soft; completely lifted/hard; incompletely lifted; and non-lifted) along with the endoscopic findings, pathological findings, and clinical course. RESULTS: Almost all completely lifted/soft lesions were mucosal cancers. Some of the completely lifted/hard lesions were staged as sm2. The incompletely lifted lesions included stages sm1 to sm3. Non-lifting lesions were almost always deeper than sm3. The lifting condition was significantly associated with the depth of invasion, and the lesion type was related to the extent of lifting but not to tumor size or recurrent disease. Recurrent disease was noted in three patients who underwent piecemeal EMR. CONCLUSIONS: The indication for EMR is easily assessed on the basis of the lifting characteristics of the tumor after submucosal injection, which was found to be significantly related to the depth of invasion. The factor limiting the indication for EMR is not the size of a tumor, but its lifting condition.     

Argon plasma coagulation in the treatment of Barrett's high-grade dysplasia and in situ adenocarcinoma

BACKGROUND AND STUDY AIMS: Endoscopic therapy of high-grade dysplasia (HGD) and superficial adenocarcinoma associated with Barrett's esophagus (BE), using Nd:YAG laser, KTP laser, or photodynamic therapy (PDT), has been reported to be effective in a curative role. Argon plasma coagulation (APC) appears to be effective in the eradication of nondysplastic Barrett's mucosa, but no results are available in the management of early neoplasms complicating BE. We report our initial experience in the application of APC in this indication. PATIENTS AND METHODS: Ten patients (mean age 74.2) with histologically proven HGD (n = 7) or in situ adenocarcinoma (n = 3) associated with BE (mean length 6 cm) and unfit for surgery were treated using APC and high-dose omeprazole (40 mg daily) until squamous re-epithelialization or complete eradication of the initially apparent lesions. Endoscopic follow-up was maintained at every 3 months. RESULTS: Complete eradication of HGD and in situ adenocarcinoma was achieved after a mean number of 3.3+/-1.5 APC sessions in 8/10 patients (80%). The eight patients with complete clearance of the neoplastic areas did not show any evidence of local recurrence during a median follow-up of 24 months (range 12-36 months). One patient with initial HGD had persistence of HGD 30 months after initial diagnosis, and one patient progressed to invasive adenocarcinoma after failure of APC and PDT. CONCLUSIONS: APC is safe and effective in the management of HGD and in situ adenocarcinoma associated with BE, and might represent an interesting alternative in selected patients who are not candidates for surgery.     

Endoscopic treatment for laterally spreading tumors in the colon

BACKGROUND AND STUDY AIMS: Laterally spreading tumors (LST) of the colon are best removed by endoscopic mucosal resection (EMR) as they extend laterally rather than vertically. Since they sometimes invade deeply into the submucosal layer, it is important to assess the depth of invasion endoscopically before treatment. In the present study, we examined the endoscopic features of a large number of LSTs in order to assess which features correlated with depth of invasion. MATERIALS AND METHODS: 257 LSTs removed at the National Cancer Center Hospital, Tokyo, between January 1988 and September 1998 were retrospectively analyzed. RESULTS: With univariate analysis, unevenness of nodules, presence of large nodules, size, histological type, and presence of depression in the tumor were significantly associated with depth of invasion. Multivariate analysis revealed that histological type and depression in the tumor were independent factors predicting massive submucosal invasion. When an LST showed: 1) even nodules without depression, or 2) uneven nodules without depression and less than 3 mm in diameter, the risk of massive submucosal invasion was 0 % (0/121) and 3.7 % (3/82), respectively. CONCLUSION: When LSTs meet the above endoscopic criteria, EMR should be the first-line treatment because of the low risk of massive submucosal invasion.     

The role of radiofrequency ablation in the management of Barrett's esophagus

Studies in the last several years have consistently shown radiofrequency ablation (RFA) to be effective, safe, and well tolerated in the treatment of nondysplastic and dysplastic Barrett's esophagus (BE). The results found at academic medical centers have been reproduced in the community setting. RFA provides a safe and cost-effective alternative to surgery or surveillance in the management of high-grade dysplasia (HGD). RFA should be given serious consideration as first-line therapy for HGD. This article reviews the evidence behind RFA to differentiate it from other management strategies in terms of efficacy, durability, safety, tolerability, and cost-effectiveness. The role of RFA in the management of BE is described, including endoscopic resection. Future directions are identified for research that will help to better define the role of RFA in the management of BE.     

Endoscopic mucosal resection for advanced sessile adenoma and early-stage colorectal carcinoma

BACKGROUND AND STUDY AIMS: The aim of this study was to evaluate the efficacy and outcomes of treatment by endoscopic mucosal resection (EMR) of patients with high-grade dysplasia (HGD) or carcinoma. PATIENTS AND METHODS: Between January 1995 and January 2002, 50 patients (35 men, 15 women) were treated by EMR for 52 sessile polyps. The median size of the polyps was 27.5 mm (range 10-60). The "lift and cut" EMR technique was used. If the lesion was poorly differentiated or infiltrated the muscularis mucosae to more than 1000 microm, the patient was referred for colectomy. In the other cases, follow-up was proposed. RESULTS: Complications occurred in 9.6 % of cases and were always treated conservatively. The rate of endoscopically complete resection was judged to be 98.1 %. Argon plasma coagulation was applied to the margins of the lesion in 21.6 % of cases. Histological examination showed 38 HGDs and 14 carcinomas. Seven patients had a lesion reaching the deep or lateral margin; four were referred for surgery; two patients for whom surgery would have been high risk were followed up, and both developed local recurrence; and one patient was followed up, without recurrence, because infiltration was less than 1000 microm. A total of 43 patients were followed up after complete excision. Two patients died during follow-up; neither death could be reliably attributed to colorectal carcinoma. Seven patients were lost during the follow-up. For 34 patients, information from a mean follow-up of 17.3 months (6 - 57) was available and recurrence was observed in five cases (15 %). CONCLUSIONS: EMR appears to be a safe and efficient treatment of HGD and early colorectal cancer. However, correct analysis of submucosal infiltration is essential to assess the completeness of the resection.     

Expansion of the indications for endoscopic mucosal resection in patients with superficial esophageal carcinoma

BACKGROUND AND STUDY AIMS: Endoscopic mucosal resection (EMR) is a minimally invasive local treatment for superficial esophageal carcinoma (SEC). The use of EMR in patients with m3 or sm1 SEC remains controversial, however. The aim of this retrospective study was to evaluate the histopathological risk factors for lymph-node metastasis and recurrence in patients with m3 or sm1 SEC. PATIENTS AND METHODS: The study subjects were 43 patients with m3 or sm1 esophageal squamous-cell carcinomas: 23 patients were treated surgically (the surgery group), and 20 were treated by EMR (the EMR group). We assessed the following variables of the specimens resected by surgery or EMR: tumor depth, maximal surface diameter of the tumor (superficial size), maximum diameter of tumor invasion at the lamina muscularis mucosae (LMM invasion width), and lymphatic invasion. The relationships of these variables to lymph-node metastasis and recurrence were examined. RESULTS: In the surgery group, lymph-node metastasis was found in four patients, all of whom had tumors with lymphatic invasion, a superficial size of at least 25 mm, and an LMM invasion width of at least 2500 microm. In the EMR group, no patient met all three of these criteria, and there was no evidence of lymph-node metastasis or distant metastasis on follow-up after EMR (median follow-up 39 months). CONCLUSIONS: In patients with m3 or sm1 SEC, tumors that have lymphatic invasion, larger superficial size, and wider LMM invasion are associated with a high risk for lymph-node metastasis. EMR might be indicated for the treatment of patients with m3 or sm1 SECs without these characteristics.     

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.     

Treatment of esophagogastric tumors

Esophageal and gastric tumors are often considered as a single group: they share similar symptoms - upper GI endoscopy with a flexible video-endoscope is the gold standard procedure of detection - similar techniques of endotherapy for cure or palliation are offered for both types of tumors. When the endoscopic procedure is performed for a superficial cancer or its precursors, with a curative intent, endoscopic mucosal resection (EMR) is generally preferred to mucosal ablation with a thermal (Nd:YAG) or non-thermal (photodynamic therapy) procedure. In addition to esophageal squamous cell cancer and gastric cancer, new indications of EMR arise in the Barrett esophagus. Guidelines for safe indications concern diameter, polypoid or non polypoid morphology with the subtypes elevated, flat and depressed, and depth of invasion. A superficial invasion in the sub-mucosa is a relative contra-indication in the esophagus, but not in the stomach. The technique of EMR is now codified with an injection into the submucosa for lifting the lesion and either suction with a cap, grasping with a forceps if a 2 channel instrument is used, or tissue incision with a needle knife. En bloc, gives better results than piecemeal resection. The most frequent complication is bleeding. When legitimate indications are respected, the results of EMR are equivalent to those of surgical resection and have reached the consensus level. The major indication in palliation is the relief of dysphagia from malignant esophageal obstruction. Increased indications are proposed for malignant pyloric obstruction. Multiple models of metal expandable and coated stents with appropriate balance between rigidity and flexibility (nitinol alloy) and enough expansive radial force are now offered. After stenting the survival period is short and there is a toll of complications.     

Evaluation of Mutational Testing of Preneoplastic Barrett's Mucosa by Next-Generation Sequencing of Formalin-Fixed,Paraffin-Embedded Endoscopic Samples?for Detection of Concurrent Dysplasia and?Adenocarcinoma in Barrett's Esophagus

Barrett''s intestinal metaplasia (BIM) may harbor genomic mutations before the histologic appearance of dysplasia and cancer and requires frequent surveillance. We explored next-generation sequencing to detect mutations with the analytical sensitivity required to predict concurrent high-grade dysplasia (HGD) and esophageal adenocarcinoma (EAC) in patients with Barrett''s esophagus by testing nonneoplastic BIM. Formalin-fixed, paraffin-embedded (FFPE) routine biopsy or endoscopic mucosal resection samples from 32 patients were tested: nonprogressors to HGD or EAC (BIM-NP) with BIM, who never had a diagnosis of dysplasia or EAC (N = 13); progressors to HGD or EAC (BIM-P) with BIM and a worse diagnosis of HGD or EAC (N = 15); and four BIM-negative samples. No mutations were detected in the BIM-NP (0 of 13) or BIM-negative samples, whereas the BIM-P samples had mutations in 6 (75%) of 8 cases in TP53, APC, and CDKN2A (P = 0.0005), detected in samples with as low as 20% BIM. We found that next-generation sequencing from routine FFPE nonneoplastic Barrett''s esophagus samples can detect multiple mutations in minute areas of BIM with high analytical sensitivity. Next-generation sequencing panels for detection of TP53 and possibly combined mutations in other genes, such as APC and CDKN2A, may be useful in the clinical setting to improve dysplasia and cancer surveillance in patients with Barrett''s esophagus.CME Accreditation Statement: This activity (“JMD 2015 CME Program in Molecular Diagnostics”) has been planned and implemented in accordance with the Essential Areas and policies of the Accreditation Council for Continuing Medical Education (ACCME) through the joint providership of the American Society for Clinical Pathology (ASCP) and the American Society for Investigative Pathology (ASIP). ASCP is accredited by the ACCME to provide continuing medical education for physicians.The ASCP designates this journal-based CME activity (“JMD 2015 CME Program in Molecular Diagnostics”) for a maximum of 36 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.CME Disclosures: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose.Esophageal adenocarcinoma (EAC) most frequently develops in patients with Barrett''s esophagus (BE), estimated to affect 3.3 million adults in the United States.¹ BE results from injury of the esophageal mucosa associated with gastroesophageal reflux, which leads to esophagitis and eventually BE. The incidence of EAC has increased greater than fivefold during the past 4 decades in the United States, paralleling the increase in detection of esophageal reflux and diagnosis of BE.² Barrett’s intestinal metaplasia (BIM) is characterized by the replacement of normal squamous esophageal mucosa by columnar epithelium with intestinal metaplasia, often occurring in the background of patches of cardiac, oxyntic, or cardiooxyntic mucosa along the length of the BE. Patients with BE may sequentially progress to low-grade dysplasia, high-grade dysplasia (HGD), and eventually EAC. Patients with BE without dysplasia have a lower EAC risk (0.1% to 0.5% per patient-year) than those with high-grade dysplasia (6% to 19% per patient-year).^3,4 Current guidelines for the prevention of EAC require repeat surveillance endoscopies with biopsies of the Barrett''s mucosa followed by pathological examination to detect BIM and dysplasia.^4–6 Unfortunately, the detection of dysplasia is hampered by sampling errors and high interobserver diagnostic variability.^7–10Known risk factors associated with EAC include male sex, older age, white race, hiatal hernia size, length of Barrett''s epithelium, smoking, and high body mass index.⁶ Recently, it was reported that persistence of BE negative for dysplasia over several endoscopic examinations identifies patients who are at low risk for development of EAC.¹¹It has been hoped that surveillance could potentially be improved by the implementation of risk stratification protocols using both clinical and biological markers because management of BE is costly and inefficient because only a small percentage of patients with BE progress to HGD or EAC.¹² Furthermore, recent data revealed that endoscopic surveillance of patients with BE was not associated with a substantially decreased risk of death from EAC.¹³Biomarkers that can be assessed in random biopsy specimens from Barrett''s mucosa negative for dysplasia with the ability to predict development or concurrent (co-existing) dysplasia elsewhere in the esophagus are warranted to improve surveillance approaches in the BE population. Previously evaluated testing approaches for EAC risk stratification in BE using esophageal biopsy samples include nuclear DNA content abnormalities, such as aneuploidy and tetraploidy; gene copy number alterations, such as loss of heterozygosity of p16 (CDKN2A) and p53 (TP53)^14,15; somatic gene mutations; and hypermethylation of a number of genes.^14,16,17 However, published studies used fresh or frozen tissue or special sampling procedures, which limits their clinical implementation, and data from studies using routine formalin-fixed, paraffin-embedded (FFPE) clinical endoscopic samples replicating the clinical setting of BE patients undergoing endoscopic surveillance have not been reported.⁶Next-generation sequencing (NGS) approaches using nucleic acids obtained from routinely processed FFPE tissues to detect mutations in cancer samples, enabling high analytical sensitivity and detection of low-frequency mutational events, are well established. However, NGS testing of preneoplastic tissues, such as BE, have not been evaluated in routine FFPE clinical samples, and there is no information regarding the minimal percentage of intestinal metaplasis in the tested mucosal tissue that may be considered for mutation testing. Therefore, we hypothesized that targeted NGS may be ideally suited for clinical application in the BE surveillance setting because it can be performed with minimal amounts of DNA from routine FFPE tissue samples, permits biomarker multiplexing, and can reach high sensitivity to detect low-frequency mutational events in heterogeneous BE tissues, where the foci of intestinal metaplasia may be small. Sensitivity of mutation detection by NGS can be 0.5% or lower due to the high level of sequencing coverage, reaching several thousand reads per amplicon when targeted sequencing is used. Therefore, targeted NGS of BE FFPE samples enables the characterization of the mutational status of hundreds to thousands of target functional sites in oncogenes and tumor suppressor genes that may be critical in BE, dysplastic precursor lesions, and EAC in individual biopsy samples collected in the clinical diagnostic setting.We used two NGS-targeted amplicon sequencing technology platforms, the Illumina (San Diego, CA) TruSeq Cancer Panel for Illumina MiSeq platform and the Ion Torrent Ion AmpliSeq Cancer Panel (Life Technologies, Carlsbad, CA), to determine whether mutations of genes known to undergo mutagenesis in esophageal dysplasia or cancer arising in BE could predict the presence of HGD or EAC through testing random nondysplastic or noncancer BE mucosa with intestinal metaplasia using endoscopic FFPE samples.     

What are the findings of esophageal cancer to be treated endoscopically?

In Japan, the results of histopathologic analyses on esophageal carcinomas have shown that almost all of them are squamous epithelial cancers. The abnormal epithelium that is difficult to differentiate by endoscopy can be easily visualized by chromoendoscopy with the use of iodine staining. Since the establishment of endoscopic mucosal resection (EMR), it has been used increasingly to treat mucosal cancers. It is necessary to diagnose accurately the depth of invasion of mucosal cancer when it is to be treated by EMR. In this article, we explain our routine techniques to visualize and interpret the lesions that are candidates for EMR. It is of great benefit to detect lesions at their early stage, which leads to the most desirable endoscopic treatment.     

Indications, Knives, and Electric Current: What's the Best?

Endoscopic submucosal dissection (ESD) was developed to overcome the limitations of conventional endoscopic mucosal resection (EMR), and ESD has been also applied for large colorectal neoplasms. Since colorectal ESD is still associated with higher perforation rate, a longer procedure time, and increased technical difficulty, the indications should be strictly considered. Generally, colorectal tumors without deep submucosal invasion or minimal possibility of lymph node metastasis, for which en bloc resection using conventional EMR is difficult, are good candidates for colorectal ESD. The ideal knife for colorectal ESD should avoid making perforations but can make a clean cut of optimal depth at one time. The ideal current for ESD differs depending on the procedure used, the surgical devices used, the tissue to be dissected, and the operator's preference. Application of the optimal indications and improvements in the technical skill and surgical devices are required for easier and safer colorectal ESD.     

Early esophageal carcinoma: endoscopic ultrasonography using the sonoprobe

Background: Almost all cases of superficial esophageal carcinoma are curable by endoscopic mucosal resection (EMR), but a precise diagnosis of the depth of tumor invasion is necessary to assess the indication for EMR. Although endoscopy has a high rate of accuracy for diagnosing the depth of tumor invasion, it depends on the experience of the examiner in interpreting surface information of the lesions. Today, endoscopic ultrasonography (EUS) is one of the most powerful techniques for obtaining objective tomographic images of a tumor. The high-frequency ultrasound probe is appropriate for EUS in cases of superficial esophageal carcinoma because of its excellent near-field resolution that provides precise ultrasound images under direct control of the endoscope. Methods: We performed EUS with the Sonoprobe System in 85 cases of superficial esophageal carcinoma before treatment and evaluated the resected specimens histopathologically. We interpreted the depth of tumor invasion based on our fundamental studies of ultrasonograms taken with a 20-MHz probe. Results: The clinical usefulness of the Sonoprobe with linear and radial scanning modes is due to its capacity to differentiate between mucosal and submucosal carcinoma by means of analyses of the muscularis mucosae. Although a clear assessment of microinvasion and lymphoid hyperplasia surrounding the tumor of interest remains speculative, the diagnostic accuracy rate for 96 lesions of superficial esophageal carcinoma reached 93% in terms of differentiating between mucosal from submucosal carcinoma. Conclusion: EUS with the Sonoprobe can play an important role in the pretreatment diagnosis of superficial esophageal carcinomas.     

内镜下黏膜切除术和内镜黏膜下剥离术治疗结肠粗蒂性息肉的疗效分析

目的 比较内镜下黏膜切除术（EMR）和内镜黏膜下剥离术（ESD）治疗结肠粗蒂性息肉,分析两种术式的术中及术后疗效,为内镜下诊疗提供参照。方法 临床病例随机分组分成EMR组、ESD组,按照随机分组表每组各50例,详细收集病灶大小、出血风险、手术时间、病理切缘阳性率、随访差异等相关临床数据。结果 ESD组手术时间明显长于EMR组（P<0.05）,ESD组术中出血（13/50）发生率明显高于EMR组（1/50）。 结论 对于蒂部直径大于1.0 cm的结肠粗蒂息肉,EMR和ESD均为安全、有效的治疗方法,在操作简易程度和出血概率方面EMR组存在一定的优势。     

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.     

Risk factors for local recurrence of superficial esophageal cancer after treatment by endoscopic mucosal resection

BACKGROUND AND STUDY AIM: The aim of this study was to elucidate the risk factors for local recurrence after endoscopic mucosal resection (EMR) treatment for superficial esophageal cancer (SEC). PATIENTS AND METHODS: We performed a retrospective analysis of the clinical course of 62 patients with 64 SECs that were treated by EMR between 1993 and 2004. Follow-up examinations by chromoscopy with iodine solution and biopsy were performed 3 months, 6 months, 12 months, and then annually after EMR. Local recurrence was defined as a histologically confirmed finding of cancer cells at the site of the preceding EMR. The contributions of lesion-related and procedure-related factors to local recurrence were analyzed retrospectively. RESULTS: Local recurrence was detected in 14/64 SECs 3-36 months after EMR. Of the lesion-related factors we assessed, local recurrence was found to be more frequent in SECs with a larger diameter (P = 0.01), larger circumferential spread (P = 0.04), or deeper invasion (P = 0.04), although the last two factors failed to demonstrate statistical significance after correction for multiple testing. Piecemeal resection did not increase the risk of local recurrence (P = 0.11), but the need for adjunctive coagulation therapy was found to increase the risk of local recurrence (P = 0.06). CONCLUSIONS: Larger SECs are associated with a higher risk of local recurrence after EMR. In patients with residual lesions, coagulation therapy does not seem to be adequate as additional endoscopic treatment.