Endoscopic mucosal resection

Conventional versus traction-assisted endoscopic submucosal dissection for large esophageal cancers: a multicenter, randomized controlled trial (with video)

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is widely used as a minimally invasive treatment for large esophageal cancers, but prolonged procedure duration and life-threatening adverse events remain matters of concern. We aimed to determine whether traction-assisted ESD (TA-ESD) is superior to conventional ESD in terms of technical outcomes.

METHODS

A superiority, randomized, phase III trial was conducted at 7 institutions across Japan. Patients with large esophageal cancer (defined as tumor diameter >20 mm) were eligible for this study. Enrolled patients were randomly assigned to undergo conventional ESD or TA-ESD. The primary endpoint was ESD procedure duration.

RESULTS

Two hundred forty-one patients were recruited and randomized. On applying exclusion criteria, 117 and 116 patients who underwent conventional ESD and TA-ESD, respectively, were included in the baseline analysis. In 1 patient, conventional ESD was discontinued because of severe perforation. Thus, the final analysis included 116 patients per group (primary analysis). The ESD procedure duration was significantly shorter for TA-ESD than for conventional ESD (44.5 minutes vs 60.5 minutes, respectively; P < .001). Moreover, no adverse events were noted in the TA-ESD group. The rate of horizontal margin involvement did not differ between the groups (10.3% vs 6.9% for conventional ESD and TA-ESD, respectively; P = .484).

CONCLUSIONS

TA-ESD was superior to conventional ESD in terms of procedure duration and was not associated with any adverse events. TA-ESD should be considered the procedure of choice for large esophageal cancers. (Clinical trial registration number: UMIN000024080.).

Outcome and risk of recurrence for endoscopic resection of colonic superficial neoplastic lesions over 2 cm in diameter

BACKGROUND

Large colorectal superficial neoplastic lesions are challenging to remove. This study aimed to assess the outcomes of routine endoscopic resection of large (≥2 cm and <3 cm) and giant (≥3 cm) lesions.

METHODS

From 4587 endoscopic resections, 265 (5.7%) large and giant lesions were removed in 249 patients. We retrospectively analyzed 125 patients (141 endoscopic mucosal resection, 73 large and 68 giant lesions) with a follow-up of 6-12 months. Rate of en bloc and piecemeal resection, recurrence and risk factors were analyzed.

RESULTS

En bloc was performed in 92 cases (65.2%) and piecemeal resection in 49 (34.8%). A complete endoscopic resection was achieved in 139 cases (98.5%) with radical resection in 84/139 cases (60.4%). Argon plasma coagulation was applied in 18/141 lesions (12.8%). A recurrence occurred in 16/139 lesions (11.5%). The risk of recurrence at one year was significantly higher for giant than large lesions (p=0.03). The recurrence risk was higher in treated than in non-argon plasma coagulation treated lesions (p=0.01).

CONCLUSIONS

endoscopic mucosal resection is a safe and effective routine treatment for large superficial neoplastic lesions. The risk factors for recurrence include giant size, non-protruding morphology, piecemeal technique and argon plasma coagulation.

[Endoscopic Resection of Sporadic Non-ampullary Duodenal Neoplasms: A Single Center Study]

BACKGROUND/AIMS

Sporadic non-ampullary duodenal neoplasms are rare and optimal treatment for these lesions remains undefined. Endoscopic resection of duodenal neoplasms is widely used recently and it is an alternative treatment strategy to surgical excision. This study aimed to evaluate the safety and efficacy of endoscopic resection of duodenal neoplasms and to determine its outcomes.

METHODS

Patients who underwent endoscopic resection for non-ampullary duodenal neoplasms between January 2005 and December 2014 were analyzed retrospectively. Data including size, morphology, histology, location and endoscopic procedural technique were reviewed. The main outcome measurements were success rate, complication, recurrence and follow-up assessments.

RESULTS

The study included 33 patients with duodenal neoplasms. The mean size of resected lesion was 8.58 mm. The results of histologic examination were as follows: 23 (69.7%) adenomas, 2 (6.1%) adenocarcinoma, 3 (9.1%) Brunner's gland tumor and 3 (9.1%) neuroendocrine tumor. Tubular adenoma was the most common type (63.6%) of non-ampullary duodenal neoplasms. Eighteen (54.5%) lesions were found in the second portion of the duodenum, and 10 (30.3%) lesions on bulb and 3 (9.1%) lesions on superior duodenal angle. Of the 33 cases, 32 (97.0%) were managed by endoscopic mucosal resection technique during a single session and one case was managed by endoscopic submucosal dissection (ESD). One episode of perforation occurred after ESD. During a median follow-up period of 5.76 months, recurrence was observed in only one case of in a patient with tubular adenoma.

CONCLUSIONS

Endoscopic resection of duodenal neoplasm is a safe and effective treatment modality that can replace surgical resection in many cases. Careful endoscopic follow-up is essential to manage recurrence or residual lesions.

Prospective study of acute complication rates and associated risk factors in endoscopic therapy for duodenal adenomas

BACKGROUND

Endoscopic therapy for duodenal adenomas is becoming increasingly important. However, only a few studies have been published on the topic, mainly with retrospective data.

METHODS

This prospective study was carried out to determine complication rates and associated risk factors during and after endoscopic therapy for duodenal adenomas. Between May 2011 and October 2012, 50 patients (with 61 duodenal adenomas) were included. Sixty-one duodenal adenomas were resected endoscopically. Complications (e.g., bleeding, pain, fever, pancreatitis, and perforation) were recorded. Associations between bleeding and other factors--sex, age, anticoagulation, location and size of adenomas, etiology, lesion morphology, resection type, and argon plasma coagulation (APC) for bleeding prophylaxis--were then investigated.

RESULTS

Bleeding was the main complication. Major bleeding occurred in four cases (6.5%) and minor bleeding in 11 (18%). One occult perforation also occurred. There was a statistically significant association between bleeding and the size of the adenoma (P = 0.012). APC for bleeding prophylaxis showed a promising trend, with an odds ratio of 0.31, reducing the bleeding risk by two-thirds in this study. However, due to the small number of six patients that received bleeding prophylaxis with APC therapy, this result was not statistically significant (P = 0.31).

CONCLUSIONS

Bleeding is the main complication in endoscopic therapy for duodenal adenomas. The bleeding risk increases significantly with adenoma size. Prophylactic APC seems to reduce the bleeding rate--however, because of the relatively small number of patients treated with APC, this partial result was not statistically relevant. Due to the relevant rate of complications, endoscopic resection of duodenal adenomas is only recommended in an in-patient setting.

Advanced precancerous lesions in the small bowel mucosa

The small intestine has comparatively low rates of epithelial cancers and is, for the most part, inaccessible to ordinary endoscopic visualization. As a result, few solid data are available on the pathological, clinical, and therapeutic aspects of epithelial dysplasia in the small intestine. In this review, we discuss the duodenal adenoma, the most readily visualized dysplastic lesion of the small intestine and the only one that can be detected in an early phase and resected endoscopically before it progresses to high-grade or invasive carcinoma. Particular emphasis is placed on the relationship between duodenal adenoma and colon neoplasia. Because of their different behaviour, detection and management of ampullary adenomas is discussed separately. Even if the absolute risk remains small, the incidence of adenocarcinoma in the small bowel is increased 32-fold in patients with ileal Crohn's disease. Therefore, the follow up and management of these patients is discussed with particular emphasis on the occurrence of dysplasia in the small bowel mucosa of the post-restorative proctocolectomy patients.

Water-jet dissector for endoscopic submucosal dissection in an animal study: outcomes of the continuous and pulsed modes

BACKGROUND

Endoscopic submucosal dissection (ESD) allows en bloc resection of early neoplastic lesions of gastrointestinal tract. Lesions are lifted by submucosal fluid injection before circumferential incision and dissection. High-pressure fluid injection using water jet (WJ) technology is already used for lifting and dissection in surgery. The study was designed to assess WJ for ESD submucosal lifting and dissection.

METHODS

An experimental, randomized comparative, "in vivo" nonsurvival animal study on 12 pigs was designed. Stomach mucosal areas were delineated and resected using three ESD techniques: technique A-syringe injection and IT knife dissection; technique B-WJ continuous injection and IT knife dissection; technique C-WJ injection and WJ pulsed dissection. Injection and dissection speeds and complications rates were assessed.

RESULTS

Water jet continuous injection is faster than syringe injection (B faster than A, p = 0.001 and B nonsignificantly faster than C, p = 0.06). IT knife dissection is significantly faster after WJ continuous injection (B faster than A, p = 0.003). WJ pulsed dissection is significantly slower than IT knife dissection (C slower than A and B, both p < 0.001). The overall procedure speed was significantly higher and the immediate bleedings rate was significantly lower for technique B than A and C (overall procedure speed p = 0.001, immediate bleedings p = 0.032 and 0.038 respectively). There were no perforations with any technique.

CONCLUSIONS

Water jet fluid continuous injection speeds up ESD, whereas pulsed WJ dissection does not.

Does endoscopic mucosal resection for large colorectal polyps allow ambulatory management?

BACKGROUND

Endoscopic mucosal resection (EMR) is an efficacious endoscopic therapy for large adenoma or confined neoplasia. The most frequent complication is delayed hemorrhage, and hemoclips appear to be an effective therapeutic option. The aim of this study was to determine if large EMR could allow ambulatory management.

METHODS

Colorectal polyps ≥20 mm in size treated by EMR in one endoscopy unit were prospectively included. The period from September 2007 to September 2008 was considered as the reference period (period 1). From September 2008 on, patients were hospitalized in an ambulatory unit. Periods from September 2008 to September 2009 (period 2), from September 2009 to September 2010 (period 3), and from September 2010 to September 2011 (period 4) were compared to the reference period. Patients receiving anticoagulation drugs were excluded from the study.

RESULTS

A total of 138 patients were treated by 139 EMRs for large colorectal polyps. EMRs were completed by at least one clip per centimeter in 10.7 %, 30.2 % (p = NS), 50 % (p = 0.015), and 76 % (p = 0.001). Ambulatory EMRs were performed in 21 %, 52.4 % (p = 0.008), 67.6 % (p = 0.02), and 88.2 % (p = 0.004) of cases during periods 1, 2, 3, and 4. The complication rate was stable during the four periods. No patients with more than one hemoclip per EMR centimeter experienced delayed bleeding.

CONCLUSIONS

The low complication rate during the four periods allows us to consider ambulatory EMR for large colorectal lesions ≥20 mm in diameter as an option. One hemoclip per centimeter may help prevent delayed hemorrhage in patients without anticoagulation drugs.

Diagnostic accuracy of probe-based confocal laser endomicroscopy and narrow band imaging in detection of dysplasia in duodenal polyps

GOALS

To estimate the accuracy of probe-based confocal laser endomicroscopy (pCLE) and narrow band imaging (NBI), individually and in combination, for classification of duodenal polyps.

BACKGROUND

Ex vivo pathologic diagnosis of duodenal polyps causes time delay, requiring separate procedures for diagnosis and therapy. It also involves small risk of pancreatitis in ampullary adenomas and can make subsequent endoscopic mucosal resection more difficult by "tacking down" mucosa. In vivo diagnosis with pCLE and NBI may avoid these complications and may guide immediate therapy.

STUDY

During high-definition white light endoscopy, 1 endoscopist (M.B.W.) performed NBI and then, pCLE of duodenal sites. Matched tissue sampling or endoscopic mucosal resection was performed. Confocal videos were recorded, de-identified, and reviewed by same endoscopist, blinded to histopathology, 1 month later. Confocal features of dysplasia in Barrett esophagus were applied for detection of duodenal dysplasia.

RESULTS

Of 65 sites from 36 participants, 24 lesions showed dysplasia, whereas 41 polyps and control sites were nondysplastic on histopathology, used as standard reference. The accuracy, sensitivity, and specificity of pCLE were 83%, 92%, and 78%, whereas that of NBI were 80%, 83%, and 78%, respectively. In subset of 49 lesions with similar pCLE and NBI diagnosis, the accuracy, sensitivity, and specificity, improved significantly and was found to be 92%, 95%, and 90%, respectively.

CONCLUSIONS

Our study suggests that pCLE has superior sensitivity as compared with NBI for detection of dysplasia in duodenal polyps. Combined accuracy of pCLE and NBI approaches that of ex vivo pathology, which may help in avoiding biopsy sampling.

Giant laterally spreading tumors of the duodenum: endoscopic resection outcomes, limitations, and caveats

BACKGROUND

Giant hemicircumferential and greater nonampullary duodenal adenomas or laterally spreading tumors (LSTs) may be amenable to safe endoscopic resection, but little data exists on outcomes or risk stratification.

DESIGN

We interrogated a prospectively maintained database of all patients who underwent endoscopic resection between January 2008 and November 2010. The resection technique was standardized. Major complications were defined as perforation, bleeding requiring readmission with hemoglobin drop of more than 20 g/L, or other substantial deviations from the usual clinical course. Outcomes were analyzed in 2 groups: giant lesions (>30 mm) and conventional duodenal polyps (<30 mm in diameter). Statistical evaluation was performed by using a χ(2) test.

RESULTS

A total of 50 nonampullary duodenal polyps and LSTs were resected from 46 patients (23 men, mean age 59.4 years, range 35-83 years). Nineteen were giant hemicircumferential and greater LSTs (mean size 40.5 mm, range 30-80 mm), and 31 were less than 30 mm in diameter (mean size 14.5 mm, range 5-25 mm). Intraprocedural bleeding occurred more frequently in giant lesions (57.8% vs 19.3%, P = .005) and was treated with a combination of soft coagulation and endoscopic clips with hemostasis achieved in all cases. Major complications, mostly bleeding related, occurred in 5 patients (26.3%) with giant lesions and 1 patient (3.2%) with a smaller lesion (P = .014). There were no deaths.

LIMITATION

Retrospective observational study in a tertiary center.

CONCLUSIONS

Endoscopic resection of giant nonampullary duodenal LSTs is a successful treatment. However, it is hazardous and associated with significantly higher complication rates, primarily bleeding, when compared with conventional duodenal polypectomy. Safer and more effective hemostatic tools are required in this high-risk location.

Upgrade of Lesions Initially Diagnosed as Low-Grade Gastric Dysplasia upon Forceps Biopsy Following Endoscopic Resection

Background/Aims

Gastric dysplasia is generally accepted to be the precursor lesion of gastric carcinoma. Approximately 25% to 35% of histological diagnoses based on endoscopic forcep biopsies for gastric dysplastic lesions change following endoscopic resection (ER). The aim of this study was to determine the predictive endoscopic features of high-grade gastric dysplasia (HGD) or early gastric cancer (EGC) following ER for lesions initially diagnosed as low-grade dysplasia (LGD) by a forceps biopsy.

Methods

To determine predictive variables for upgraded histology (LGD to HGD or EGC). The lesion size, gross endoscopic appearance, location, and surface nodularity or redness as well as the presence of a depressed portion, Helicobacter pylori infection, and intestinal metaplasia were retrospectively investigated.

Results

Among 251 LGDs diagnosed by an initial forceps biopsy, the diagnoses of 100 lesions (39.8%) changed following the ER; 56 of 251 LGDs (22.3%) were diagnosed as HGD, 39 (15.5%) as adenocarcinoma, and 5 (2.0%) as chronic gastritis. In a univariate analysis, large lesions (>15 mm), those with a depressed portion, and those with surface nodularity were significantly correlated with a upgraded histology classification following ER. In a multivariate analysis, a large size (>15 mm; odds ratio [OR], 2.8; 95% confidence interval [CI], 1.46 to 5.43) and a depressed portion in the lesion (OR, 2.7; 95% CI, 1.44 to 5.03) were predictive factors for upgraded histology following ER.

Conclusions

Our study shows that a substantial proportion of diagnoses of low-grade gastric dysplasias based on forceps biopsies were not representative of the entire lesion. We recommend ER for lesions with a depressed portion and for those larger than 15 mm.

Essence of affinity and specificity of peanut agglutinin-immobilized fluorescent nanospheres with surface poly(N-vinylacetamide) chains for colorectal cancer

We have designed a novel colonoscopic imaging agent that is composed of submicron-sized fluorescent polystyrene nanospheres with two functional groups - peanut agglutinin (PNA) and poly(N-vinylaceamide) (PNVA) - on their surfaces. PNA is a targeting moiety that binds to β-d-galactosyl-(1-3)-N-acetyl-d-galactosamine (Gal-β(1-3)GalNAc), which is the terminal sugar of the Thomsen-Friedenreich antigen that is specifically expressed on the mucosal side of colorectal cancer cells; it is anchored on the nanosphere surface via a poly(methacrylic) acid (PMAA) linker. PNVA is immobilized to enhance the specificity of PNA by reducing nonspecific interactions between the imaging agent and normal tissues. The essential nature of both functional groups was evaluated through in vivo experiments using PNA-free and PNVA-free nanospheres. The imaging agent recognized specifically tumors on the cecal mucosa of immune-deficient mice in which human colorectal cancer cells had been implanted; however, the recognition capability disappeared when PNA was replaced with wheat germ agglutinin, which has no affinity for Gal-β(1-3)GalNAc. PNA-free nanospheres with exclusively surface PNVA chains rarely adhered to the cecal mucosa of normal mice that did not undergo the cancer cell implantation. In contrast, there were strong nonspecific interactions between normal tissues and PNA-free nanospheres with exclusively surface PMAA chains. In vivo data proved that PNA and PNVA were essential for biorecognition for tumor tissues and a reduction of nonspecific interactions with normal tissues, respectively.

Sporadic nonampullary duodenal adenoma in the natural history of duodenal cancer: a study of follow-up surveillance

OBJECTIVES

Although sporadic nonampullary duodenal adenoma (SNDA) is regarded as a precancerous lesion, its natural course is uncertain. The aim of this study was to evaluate the risk of development of adenocarcinoma in SNDA lesions initially diagnosed as showing low-grade dysplasia (LGD; category 3) or high-grade dysplasia (HGD; category 4.1).

METHODS

We analyzed 68 SNDAs, diagnosed based on initial and subsequent biopsies, in 66 consecutive patients. Of these, 46 (43 LGD lesions, 3 HGD lesions) were followed up for ≥6 months without treatment (mean 27.7±16.9 months; range 6-72 months), including 8 lesions that were eventually resected during follow-up. Sixteen lesions (eight LGD lesions, eight HGD lesions) were resected immediately, either endoscopically or surgically, and six lesions were excluded because of a short follow-up (<6 months). The histopathological diagnoses and macroscopic changes were evaluated.

RESULTS

Among the 43 LGD lesions followed up for ≥6 months, 34 (79.1%) showed no histopathological changes during follow-up, whereas the remaining 9 (20.9%) showed progression to HGD, including 2 (4.7%) that progressed eventually to noninvasive carcinoma (category 4.2). Macroscopically, 76.7% (33 of 43) of the LGD lesions showed no notable changes in size, 16.3% (7 of 43) became undetectable, 4.7% (2 of 43) reduced in size, and 2.3% (1 of 43) became larger in size. In contrast, all the three HGD lesions that were followed up for ≥6 months remained unchanged histologically, based on biopsy, and showed no notable macroscopic changes, although one of these HGD lesions resected endoscopically revealed evidence of noninvasive carcinoma. Although we diagnosed all lesions as HGD from biopsy samples, a high percentage of cancers (54.5%, 6 of 11) were diagnosed from resected specimens. A multivariate analysis identified HGD diagnosed at first biopsy and a lesion diameter of ≥20 mm as being significantly predictive of progression to adenocarcinoma.

CONCLUSIONS

LGD lesions show a low risk of progression to adenocarcinoma, but some risk of progression to HGD, which warrants careful follow-up biopsy. However, HGD lesions and large SNDAs≥20 mm in diameter show a high risk of progression to adenocarcinoma. Therefore, they should be treated immediately.

A potential of peanut agglutinin-immobilized fluorescent nanospheres as a safe candidate of diagnostic drugs for colonoscopy

We designed peanut agglutinin (PNA)-immobilized fluorescent nanospheres as a non-absorbable endoscopic imaging agent capable of being administered intracolonically. Following our previous researches with evidence that the imaging agent recognized small-sized colorectal tumors on the mucosal surface with high affinity and specificity in animal experiments, a potential of this nanoprobe as a drug candidate was evaluated from a safety perspective. The imaging agent detects colorectal tumors through recognition of the tumor-specific antigen by PNA immobilized on the nanosphere surface, and the detection is made via the fluorescent signal derived from coumarin 6 encapsulated into the nanosphere core. The stability studies revealed that the high activity of PNA was maintained and there was no significant leakage of coumarin 6 after intracolonic administration of the imaging agent. Cytotoxicity studies indicated that no local damage to the large intestinal membrane was induced by the imaging agent. Further, in vitro and in vivo permeation studies demonstrated that there was no significant permeation of the imaging agent through the monolayer of cultured cells and that the imaging agent administered locally to the luminal side of the large intestine was almost completely recovered from the administration site. Therefore, we concluded that the imaging agent is a safe and stable probe which remains in the large intestine without systemic exposure.

Rectal laterally spreading tumors successfully treated in two steps by endoscopic submucosal dissection and endoscopic mucosal resection

BACKGROUND

Endoscopic submucosal dissection (ESD) is an advanced technique of therapeutic endoscopy alternative to endoscopic mucosal resection (EMR) for superficial gastrointestinal neoplasms >2 cm. ESD allows for the direct dissection of the submucosa and large lesions can be resected en bloc. ESD is not limited by resection size, increases histologically complete resection rates and may reduce the local recurrence. Nevertheless, the technique is time-consuming, technically demanding and associated with a high complication rate. To reduce the risk of complications, different devices and technical advances have been proposed with conflicting results and, still, ESD en bloc resections of huge lesions are associated with increased complications.

CASE PRESENTATION

We successfully used a combined ESD/EMR technique for huge rectal laterally spreading tumors (LSTs). ESD was used for circumferential resection of 2/3 of the lesion followed by piecemeal resection (2-3 pieces) of the central part of the tumour. In all three patients we obtained the complete dissection of the polyp and the complete histological evaluation in absence of complications and recurrence at 6 months' follow up.

CONCLUSIONS

In the treatment of rectal LSTs, the combined treatment - ESD/EMR resection may be considered a suitable therapeutic option, indicated in selected cases as an alternative to surgery, in which the two techniques are neither reliable nor safe separately. However, to confirm our results, larger trials with longer follow up are required together with improvement of the technique and of the technical devices.

Endoscopic mucosal resection of colorectal polyps in typical UK hospitals

AIM: To evaluate the outcomes of endoscopic mucosal resection (EMR) for colorectal polyps, with particular regard to procedural complications and recurrence rate, in typical United Kingdom (UK) hospitals that perform an average of about 25 colonic EMRs per year.

METHODS: A total of 239 colorectal polyps (≥ 10 mm) resected from 199 patients referred to Rochdale Infirmary, Salford Royal Hospital and Royal Oldham Hospital for EMR between January 2003 and January 2009 were studied.

RESULTS: The mean size of polyps resected was 19.6 ± 12.4 mm (range 10-80 mm). The overall major complication rate was 2.1%. Complications were less frequent with non-adenomas compared with the other groups (Pearson’s χ² test, P < 0.0001). Resections of larger-sized polyps were more likely to result in complications (unpaired t-test, P = 0.021). Recurrence was associated with histology, with carcinoma-in-situ more likely to recur compared with low-grade dysplasia [hazard ratio (HR) 186.7, 95% confidence interval (95% CI): 8.81-3953.02, P = 0.001]. Distal lesions were also more likely to recur compared with right-sided and transverse colon lesions (HR 5.93, 95% CI: 1.35-26.18, P = 0.019).

CONCLUSION: EMR for colorectal polyps can be performed safely and effectively in typical UK hospitals. Stricter follow-up is required for histologically advanced lesions due to increased recurrence risk.

Efficacy and long-term outcome of endoscopic treatment of sporadic nonampullary duodenal adenoma

BACKGROUND/AIMS

Endoscopic resection has proven to be a safe and effective alternative to surgery for duodenal adenomas. However, few data are available on the adequacy of resection and long-term outcomes. This study evaluated the efficacy and longterm endoscopic findings in a cohort of Korean patients who underwent endoscopic mucosal resection (EMR) of sporadic duodenal adenomas.

METHODS

Seventeen patients with nonampullary duodenal adenomas without familial polyposis syndrome and who were treated by EMR between January 2001 and December 2007 were evaluated retrospectively. Their management, follow-up, and outcomes were reviewed.

RESULTS

In total, seventeen lesions were removed from EMR in 17 patients (mean age, 59.3 years; 6 women, 11 men). The mean size of the tumors was 15.1 mm (median, 13 mm, range, 8-27 mm). Of these 17 adenomas, 16 adenomas were tubulous and 1 was tubulovillous. The EMR was performed successfully in all 17 patients in a single session. After a median follow-up period of 29 months (range, 13-72 months), all patients remained in remission. One patient had bleeding at the site of the EMR. There were no perforations after the EMR.

CONCLUSIONS

EMR for sporadic duodenal adenomas seemed to be a safe and effective treatment modality.

Detection of early colorectal cancer imaged with peanut agglutinin-immobilized fluorescent nanospheres having surface poly(N-vinylacetamide) chains

Peanut agglutinin (PNA)-immobilized fluorescent nanospheres were designed as a novel imaging agent for colonoscopy. PNA is a targeting moiety that binds to beta-D-galactosyl-(1-3)-N-acetyl-D-galactosamine, which is the terminal sugar of the Thomsen-Friedenreich antigen that is specifically expressed on the mucosal side of colorectal cancer cells. The in vivo performance of the imaging agent was evaluated using a human colorectal cancer orthotopic animal model. Human colorectal adenocarcinoma cell lines, HT-29, HCT-116, and LS174T, were implanted on the cecal serosa of immune-deficient mice. A loop of the tumor-bearing cecum was made, and the luminal side was treated with the imaging agent. Strong fluorescence was observed at several sites of the cecal mucosa, irrespective of cancer cell type. Microscopic histological evaluation of the cecal mucosa revealed that bright areas with fluorescence derived from the imaging agent and dark areas without the fluorescence well denoted the presence and absence, respectively, of the invasion of implanted cancer cells on the mucosal side. This good correlation showed that PNA-immobilized fluorescent nanospheres recognized millimeter-sized tumors on the cecal mucosa with high affinity and specificity.

Endoscopic closure of duodenal perforations by using an over-the-scope clip: a randomized, controlled porcine study

BACKGROUND

Duodenal perforations during diagnostic upper endoscopy are rare; however, when therapeutic techniques are performed, the reported incidence is as great as 2.8%. Surgical repair is usually mandated, but it is associated with significant morbidity and mortality.

OBJECTIVE

To compare closure of duodenal perforations by using an over-the-scope clip (OTSC) with a surgical closure.

DESIGN

Randomized, controlled animal study.

SETTING

Animal facility laboratory.

ANIMALS

Domestic pigs (24 females).

INTERVENTIONS

Large (10-mm) duodenal perforations were created by using an endoscopic needle-knife. The animals were randomly assigned to either open surgical repair (n=12) or endoscopic closure by using the OTSC system (n=12). Pressurized leak tests were performed during necropsy.

MAIN OUTCOME MEASUREMENTS

One major bleed occurred because of a liver injury during creation of the duodenotomy. Mean time for endoscopic closure was 5 minutes (range, 3-8 min; SD +/- 2). No complications occurred during any of the closure procedures. At necropsy, all OTSC and surgical closures demonstrated complete sealing of duodenotomy sites. Pressurized leak tests demonstrated a mean burst pressure of 166 mm Hg (range, 80-260; SD +/- 65) for OTSC closures and 143 mm Hg (range, 30-300, SD +/- 83) for surgical sutures. Ex vivo intact duodenal specimens exhibited a mean burst pressure of 247 mm Hg (range, 200-300; SD +/- 35), which was significantly higher compared with in vivo OTSC and surgical closures (P < .01). There were no significant differences between burst pressures of OTSC and surgical closures (P = .461).

LIMITATIONS

Nonsurvival setting.

CONCLUSIONS

Endoscopic closure of duodenal perforations by using the OTSC system is comparable with surgical closure in a nonsurvival porcine model. This technique is easy to perform and seems suitable for repairing duodenal perforations.

Prediction of histology and invasive depth of colorectal neoplasia based on morphology of surface depression using magnifying chromocolonoscopy

BACKGROUND AND STUDY AIMS

Estimation of histology and depth of invasion in early colorectal neoplasia is essential for patient treatment. We therefore conducted a prospective study to examine whether the morphology of depression area contained at the surface of colorectal neoplasia can be used for predicting the histology and invasive depth.

METHODS

A series of 228 consecutive patients with 296 colorectal lesions were studied. All lesions were evaluated by magnifying chromocolonoscopy. Surface depression contained in the lesions was noted and the depressive morphology was further divided into two subgroups of type I and type II. All of the lesions were resected endoscopically or surgically and examined histologically for comparison.

RESULTS

A total of 296 lesions were evaluated, of which 66 (22.3%) contained an area of central depression, including 43 in nonpolypoid (flat and depressed) lesions (66%) and 23 in polypoid (10%). The overall accuracy of depressive morphology for distinction between low-grade dysplasia and high-grade dysplasia/invasive cancer, and between m-sm1 and sm2-sm3 was 86.4% and 84.8%, respectively.

CONCLUSIONS

Depression was predominantly contained in nonpolypoid colorectal neoplasia. Morphology of depression observed by magnifying chromocolonoscopy could be used as a complementary method to assess the degree of atypia and invasive depth in colorectal neoplasia.

Clinicopathologic features and endoscopic mucosal resection of laterally spreading tumors: experience from China

BACKGROUND

Laterally spreading tumors (LSTs) are being increasingly reported nowadays in Japan and the western countries with the application of magnification chromoendoscopy. The aim of this study was to analyze the clinicopathologic features of LSTs and to assess the outcome and safety of endoscopic mucosal resection (EMR) in China.

PATIENTS AND METHODS

One hundred nine patients with LSTs who underwent magnification chromoendoscopy were studied retrospectively. Clinicopathological features of 111 LSTs were analyzed. The efficacy and safety of EMR was assessed in 79 LSTs based on the outcome of follow-up colonoscopy and resection-related complications.

RESULTS

A total of 111 LSTs were diagnosed in 109 patients, including 89 (80%) laterally spreading tumor-granular (LST-G) type and 22 (20%) laterally spreading tumor-non-granular (LST-NG) type. There was significant difference in the dominant pit pattern between LST-G type and LST-NG type (p < 0.001). Type IV pit pattern (62%) was the main crypt pattern in LST-G type; whereas, type IIIL (50%) and type V pit pattern (36%) were predominant crypt patterns in LST-NG type. EMR was performed for 103 lesions. Six of the nine lesions with type V(I) pit pattern were completely resected by EMR. Eleven (14%) local recurrent lesions were detected in 79 follow-up lesions and were treated successfully during the follow-up.

CONCLUSIONS

The type of dominant pit pattern was different between LST-G type and LST-NG type. Many LSTs with a type V(I) pit pattern can be completely resected by EMR. EMR technique is a safe and efficacious treatment method for LST.

Endoscopic mucosal resection for early gastric cancer

BACKGROUND

The treatment of early gastric cancer (EGC) using endoscopy, namely endoscopic mucosal resection (EMR), has been adopted for about 20 years, but the effectiveness and safety of the modality are still controversial. Furthermore, the risk of bias of trials of this technique has not been assessed systematically.

OBJECTIVES

The purpose of this review was to compare the effectiveness and safety of endoscopic mucosal resection with gastrectomy for the treatment of early gastric cancer.

SEARCH STRATEGY

Searches were conducted on the Cochrane Central Register of Controlled Trials (CENTRAL) which includes the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group (UGPD) Trials Register (The Cochrane Library 2005, Issue 1), MEDLINE (1966 to March 2005), EMBASE (1980 to March 2005), CINAHL (1985 to March 2005) and CBM (Chinese BioMedical Database 1982 to 2002). The searches of CENTRAL, MEDLINE and EMBASE were updated in February 2006 and January 2009. Reference lists from trials selected by electronic searching were handsearched to identify further relevant trials. Published abstracts from conference proceedings from the United European Gastroenterology Week (published in Gut) and Digestive Disease Week (published in Gastroenterology) were handsearched. Members of the Cochrane UGPD Group, and experts in the field were contacted and asked to provide details of outstanding clinical trials and any relevant unpublished materials.

SELECTION CRITERIA

All randomised controlled trials of early gastric cancer patients involving a treatment arm of EMR and a comparison arm of gastrectomy were to be included, but no RCTs were found.

DATA COLLECTION AND ANALYSIS

Three review authors (YP Wang, C Bennett and T Pan) independently assessed the eligibility of potential trials and extracted the data.

MAIN RESULTS

There were no randomised controlled trials identified for systematic review. Available evidence derived from non-randomised controlled trials is discussed in the main text of this review.

AUTHORS' CONCLUSIONS

There is a lack of randomised controlled trials in which endoscopic mucosal resection (EMR) is compared with gastrectomy for early gastric cancer. There is, therefore, a need for well-designed randomised controlled trials to determine the effects of EMR compared to gastrectomy.

Endoscopic transanal resection of rectal adenomas using the urological resectoscope

OBJECTIVE

Large sessile rectal adenomas are often difficult to excise and several different techniques have been described. This study evaluates the results of adenoma excision by endoscopic transanal resection using the urological resectoscope by a single surgeon in a UK district general hospital.

METHOD

Between January 1989 and November 2004, data on all patients treated by endoscopic transanal resection of benign rectal tumours using a urological resectoscope (ETAR) were prospectively collected and analysed.

RESULTS

Forty patients (50% male, median age 72 years) underwent a total of 81 endoscopic transanal resections. The tumour characteristics were: size > 2 cm (83%), location in lower 2/3 of rectum (83%) and extensive circumferential carpet-like appearances (13%). Fifty percent of the patients required only one procedure to achieve clearance. Mean operative time was 26 min (range 10-65 min). Seventy-eight percent of the patients were discharged home within 24 h. Postoperative morbidity was 8% and in-hospital mortality was zero. Histology revealed severe dysplasia in 48% of the tumours and five patients were incidentally found to have foci of rectal adenocarcinoma. With a median follow-up of 47 months (range 2-162 months), local recurrences occurred in 13% (n = 5) of patients. All, except one, were treated successfully with further endoscopic transanal resections.

CONCLUSION

ETAR is simple and safe for managing rectal adenomas.

EMR of large, sessile, sporadic nonampullary duodenal adenomas: technical aspects and long-term outcome (with videos)

BACKGROUND

EMR is a viable alternative to surgery for removal of large mucosal neoplastic lesions of the entire GI tract. Few studies have, however, been published on the safety, efficacy, and technical aspects of EMR in the duodenum.

OBJECTIVE

Our purpose was to evaluate the efficacy and safety of EMR of large (>15 mm) duodenal adenomas.

DESIGN

Retrospective evaluation of a defined patient cohort.

SETTING

Tertiary academic referral center.

PATIENTS

Patients with large (>15 mm) sporadic nonampullary duodenal adenomas managed by a standardized technique who were referred by other specialist endoscopists for endoscopic treatment.

METHODS

Five-year data from patients undergoing EMR for large duodenal adenomas were reviewed retrospectively. Immediate and delayed complications were recorded.

RESULTS

Twenty-one lesions were removed by EMR in 23 patients (mean age 62.2 years, 13 female, 10 male). The mean size of lesions resected was 27.6 mm (median 20 mm, range 15-60 mm). Post-EMR histologic examination revealed mucosal adenocarcinoma in 1, low-grade tubulovillous adenoma (TVA) in 16, high- or focal high-grade TVA in 3 patients, and 1 with both high-grade TVA and carcinoid. EMR was performed successfully in 18 patients during a single session. Two patients required 2 sessions and 1 required 3 sessions for complete resection. The median follow-up was 13 months (range 4-44 months). During follow-up, 5 patients had minor residual adenomas that were treated successfully with snare resection and/or argon plasma coagulation. One patient had EMR site bleeding. There were no perforations.

LIMITATION

Retrospective study.

CONCLUSION

EMR for large sporadic nonampullary duodenal adenomas is a safe and effective technique.

Salvage endoscopic submucosal dissection for residual or local recurrent intraepithelial neoplasia in the colorectum: a prospective analysis

OBJECTIVE

A prospective technical feasibility study of cap assisted ESD for 'curative intent' in patients with residual or local neoplastic recurrence following EMR. Primary end points were second stage R0 resection rate, safety and recurrence.

METHOD

Salvage ESD was performed using the Olympus GIF-XQ240 gastroscope and KD-630L insulation tipped knife. Thirty-day mortality, re-admission rates, complications and histological resection status were collected prospectively up to 9 months following index resection.

RESULTS

Thirty patients met eligibility criteria. Index R0 resection was achieved in 25/30 (83%) lesions. One patient underwent surgical excision with a second receiving a curative second stage dissection. Ninety-six per cent (29/30) patients were discharged within 24 h of the procedure with a 0% 30-day mortality and re-admission rate. Bleeding occurred in 5/30 (16%) treated successfully with endoluminal haemostasis. There were no perforations. Overall 'cure' rates at short-term follow-up [median 6/12 (range; 3-18)] was 96%.

CONCLUSION

This novel application of ESD for first line 'salvage' therapy in treating residual or locally recurrent neoplastic disease may be a safe, minimally invasive and cost effective alternative to direct surgical resection in a select patient cohort.

In vitro/in vivo biorecognition of lectin-immobilized fluorescent nanospheres for human colorectal cancer cells

Peanut agglutinin (PNA)-immobilized polystyrene nanospheres with surface poly(N-vinylacetamide) (PNVA) chains encapsulating coumarin 6 were designed as a novel colonoscopic imaging agent. PNA was a targeting moiety that binds to beta-D-galactosyl-(1-3)-N-acetyl-D-galactosamine, which is the terminal sugar of the Thomsen-Friedenreich antigen that is specifically expressed on the mucosal side of colorectal cancer cells. PNVA was immobilized with the aim of reducing nonspecific interactions between imaging agents and normal tissues. Coumarin 6 was encapsulated into nanosphere cores to provide endoscopically detectable fluorescence intensity. After incubation of imaging agents with human cells, the fluorescence intensity of imaging agent-bound cells was estimated quantitatively. The average fluorescence intensity of any type of colorectal cancer cell used in this study was higher than that of small intestinal epithelial cells that had not exposed the carbohydrate. The in vivo performance of imaging agents was subsequently evaluated using a human colorectal cancer orthotopic animal model. Imaging agent-derived strong fluorescence was observed at several sites of the large intestinal mucosa in the tumor-implanted nude mice after the luminal side of the colonic loop was contacted with imaging agents. In contrast, when mice that did not undergo tumor implantation were used, the fluorescence intensity on the mucosal surface was extremely low. Data indicated that imaging agents bound to colorectal cancer cells and the cancer cell-derived tumors with high affinity and specificity.

Achieving R0 resection in the colorectum using endoscopic submucosal dissection

BACKGROUND

Endoscopic mucosal resection is established for the removal of non-invasive colorectal tumours smaller than 20 mm but is unsatisfactory for larger lesions. Endoscopic submucosal dissection (ESD) enables en bloc resection of lesions larger than 20 mm. A UK-based prospective feasibility study of ESD for colorectal tumours was undertaken; primary endpoints were R0 resection, safety and recurrence.

METHODS

Patients with Paris 0-II adenomas or laterally spreading tumours (LSTs) greater than 20 mm in diameter were enrolled between November 2004 and August 2006. Lesions were assessed by chromoscopy and high-frequency ultrasonography. Dysplasia, resection status, 30-day complication rates and recurrence after ESD were recorded.

RESULTS

ESD was performed in 42 of 56 identified patients; en bloc resection was possible in 33. Fourteen Paris 0-II lesions and 28 LSTs were identified; 40 were dysplastic adenomas and two adenocarcinomas. R0 resection was achieved in 31 patients (74 per cent). The 30-day mortality rate was 0 per cent. Perforation occurred in one patient and uncomplicated bleeding in five. The 6-month cure rate was 81 per cent (34 of 42 patients).

CONCLUSION

High cure rates are achievable using ESD for Paris 0-II adenomas and LSTs greater than 20 mm in diameter, with R0 resection possible in most patients. ESD is feasible throughout the colorectum with no increase in complication rates. It should be considered for selected Tim/T1 N0 colorectal lesions.

Risk factors for delayed postendoscopic mucosal resection hemorrhage in patients with gastric tumor

OBJECTIVE

Although endoscopic mucosal resection has been recognized as the standard treatment for gastric mucosal neoplasm, postendoscopic mucosal resection hemorrhage remains a major complication of endoscopic mucosal resection, and this problem seems to be increasing owing to the development of invasive techniques. The aims of this study were to determine the incidence and grade of postendoscopic mucosal resection hemorrhage and to identify risk factors for delayed postendoscopic mucosal resection hemorrhage in patients with gastric neoplasm.

METHODS

Data of endoscopic mucosal resections performed by three endoscopists were retrospectively collected over 8 years and then analyzed. Immediate postendoscopic mucosal resection hemorrhage was defined as bleeding during the procedure. Delayed postendoscopic mucosal resection hemorrhage was defined when two of the four following parameters were satisfied after the endoscopic mucosal resection period; (i) hematemesis, melena or dizziness, (ii) hemoglobin loss >2 g/dl, (iii) blood pressure decrease >20 mmHg or pulse rate increase >20/min and (iv) Forrest I or IIa-IIb on follow-up endoscopy.

RESULTS

A total of 157 patients (mean age: 64 years, male : female=44 : 113) were reviewed. Twenty-nine (18.5%) and 13 patients (8.3%) presented with immediate and delayed postendoscopic mucosal resection hemorrhage, respectively. Multivariate logistic regression analysis revealed that the patient's age (<or=65 years; odds ratio 6.11, 95% confidence interval 1.12-33.43), the size of lesion (>15 mm; odds ratio 5.90, 95% confidence interval 1.13-30.87) and the experience of the endoscopist (<or=5 years; odds ratio 16.31, 95% confidence interval 1.46-181.97) were significantly predictive variables for the delayed postendoscopic mucosal resection hemorrhage.

CONCLUSION

Considering the higher risk of delayed postendoscopic mucosal resection hemorrhage, careful preparation and close monitoring are required for patients who are less than 65 years, have large lesions over 15 mm or if the procedures were performed by an inexperienced endoscopist.

Novel colorectal endoscopic in vivo imaging and resection practice: a short practice guide for interventional endoscopists

Colorectal cancer remains a leading cause of cancer death in the UK. With the advent of screening programmes and developing techniques designed to treat and stage colorectal neoplasia, there is increasing pressure on the colonoscopist to keep up to date with the latest practices in this area. This review looks at the basic principles behind endoscopic mucosal resection and forward to the potential endoscopic tools, including high-magnification chromoscopic colonoscopy, high-frequency miniprobe ultrasound and confocal laser scanning endomicroscopic colonoscopy, that may soon become part of routine colorectal cancer management.

Endoscopic mucosal resection of large sessile colorectal polyps with submucosal injection of hypertonic 50 percent dextrose-epinephrine solution

PURPOSE

Before endoscopic mucosal resection of large sessile colorectal polyps, injection of solution into submucosa cushions and isolates the tumor, although there is little information as to which solution with optimal effect should be used. This study investigated the effectiveness of endoscopic mucosal resection by use of a hypertonic dextrose plus epinephrine solution for large sessile colorectal polyps.

METHODS

We removed 59 large sessile colorectal polyps in 59 patients by introducing an endoscopic submucosal hypertonic dextrose plus epinephrine injection technique. Endoscopic evaluations were repeated at 3, 6, and 12 months or longer. If no residual tumor was observed endoscopically and histologically at one year or more, the patient was considered to be "cured." The main outcome measurements were the mean amount of solution injected, mean disappearance time of solution, safety, complications, and recurrence at follow-up.

RESULTS

Of the 59 large sessile colorectal polyps, 23 (39 percent) were resected en bloc and 36 (61 percent) piecemeal. The mean amount of hypertonic dextrose plus epinephrine solution injected was 24.42 +/- 17.52 ml, and its mean disappearance time was 13.61 +/- 5.21 (range, 7-21) minutes. Of the 36 patients treated with piecemeal resection, 18 (50 percent) required additional endoscopic interventions. In patients who entered the follow-up surveillance protocol for one year or longer, the cure rate by en bloc resection was 100 percent (23/23) and that by piecemeal intervention was 96.78 percent (30/31). Four patients (6.8 percent) had local bleeding after endoscopic mucosal resection that was mainly controlled endoscopically.

CONCLUSIONS

Endoscopic mucosal resection after submucosal hypertonic dextrose plus epinephrine solution injection, with an intensive follow-up program, seems to be a safe and effective treatment for large sessile colorectal polyps.

Single-band mucosectomy for granular cell tumor of the esophagus: safe and easy technique

BACKGROUND

Mucosectomy involves resection of a digestive wall fragment that frequently removes a part or even all of the submucosal mass. The single-band mucosectomy technique was used to remove a granular cell tumor (GCT) of the esophagus. Only 3% of GCTs, which are relatively uncommon neoplasms, arise in the esophagus. Ultrasonography has allowed for more frequent recognition and better definition of this disease. Until recently, surgical resection of the esophagus has been the only treatment alternative to endoscopic surveillance. Endoscopic techniques such as mucosal resection (EMR), laser, and argon plasma have been proposed as safe and effective alternatives to surgery. However, to date, only a few reports of these endoscopic techniques have been published. This study aimed to evaluate the safety and feasibility of single-band mucosectomy for removing a GCT of the esophagus.

METHODS

Six patients (1 man and 5 women; mean age, 45 years) with a GCT were studied between January 2000 and May 2004. They underwent EMR after endoscopic ultrasonography.

RESULTS

The EMR was performed with a diathermic loop after injection of saline solution into the esophageal wall. Only one session was necessary for removal of the tumor from all 6 patients, and no complication was observed. During a mean clinical endoscopic follow-up period of 36 months, no recurrences, scars, or stenoses were observed.

CONCLUSIONS

These findings show EMR to be a safe and effective technique that allows complete removal of GCTs. Furthermore, this technique provides tissue for a definitive pathologic diagnosis, which laser and argon plasma do not provide. We recommend EMR as the treatment of choice for GCTs after an accurate ultrasonographic evaluation.

Endoscopic mucosal resection for early gastric cancer

BACKGROUND

The treatment of early gastric cancer (EGC) using an endoscopy, namely, endoscopic mucosal resection (EMR), has been adopted for about 20 years, but the effectiveness and the safety of the modality are still controversial. The quality of these trials has not been assessed systematically.

OBJECTIVES

The purpose of this review was to compare the effectiveness and the safety of EMR with gastrectomy for the treatment of EGC.

SEARCH STRATEGY

Searches were conducted on the Cochrane Central Register of Controlled Trials - CENTRAL (which includes the Cochrane Upper Gastrointestinal and Pancreatic Diseases Group Trials Register) on The Cochrane Library (Issue 1 2005) MEDLINE (1966 to March 2005) and EMBASE (1980 to March 2005), CINAHL (1985-March 2005) and CBM (Chinese BioMedical Database 1982 -2002). Reference lists from trials selected by electronic searching were handsearched to identify further relevant trials. Published abstracts from conference proceedings from the United European Gastroenterology Week (published in Gut) and Digestive Disease Week (published in Gastroenterology) were handsearched. Members of the Cochrane UGPD Group, and experts in the field were contacted and asked to provide details of outstanding clinical trials and any relevant unpublished materials

SELECTION CRITERIA

All randomised controlled trials of EGC patients involving a treatment arm of EMR and a comparison arm of gastrectomy were to be included, but no RCTs were found.

DATA COLLECTION AND ANALYSIS

Three reviewers (YP Wang, C Bennett and T Pan) independently assessed the eligibility of potential trials and extracted the data.

MAIN RESULTS

There are no included randomised control trials for the systematic review. Available evidence derived from non-randomised controlled trials is discussed in the main text of this review.

AUTHORS' CONCLUSIONS

There is a lack of randomised controlled trials in which EMR is compared with gastrectomy for EGC. There is a need for well designed randomised controlled trials to determine the effects of EMR compared to gastrectomy.

20-MHz high-frequency endoscopic ultrasound-assisted endoscopic mucosal resection for colorectal submucosal lesions: a prospective analysis

GOALS

To prospectively assess the safety and efficacy of high-frequency ultrasound assisted mini-probe endoscopic mucosal resection for the treatment of colorectal submucosal tumors. Primary endpoints were tumor free vertical/horizontal resection margins and positive histopathologic diagnosis. Outcome data over a 24-month period were assessed.

BACKGROUND

A 20-MHz high-frequency mini-probe ultrasound is an accurate modality for the diagnosis of stage T1m and T1 colorectal lesions. Few studies have addressed the safety and efficacy of this technology as applicable to submucosal lesions of the colorectum.

METHODS

Thirty patients underwent high-frequency mini-probe ultrasound-guided endoscopic mucosal resection of 30 lesions (<20 mm diameter) using the inject and cut technique. Repeat endoscopy and ultrasound was performed at 3, 6, and 12 months post-"index" resection.

RESULTS

A total of 27 lesions (90%) underwent complete resection with negative histologic margin status (median diameter, 8 mm; range, 3-20 mm). No statistical difference (P > 0.1) was observed between submucosal lesion position and histologic resection margin negativity. Three rectal lesions (10%) within the submucosal layer 3 failed to separate from the muscularis and underwent transanal excision of tumor. Bleeding occurred in 1 patient (3%). No recurrence was evident at the resection site in 27 cases (median follow-up, 9 months; range, 4-18 months).

CONCLUSIONS

High-frequency mini-probe ultrasound-guided endoscopic mucosal resection is a safe and effective therapeutic modality for submucosal lesions of the colorectum. The technique offers a single-stage diagnostic and therapeutic technique for selected submucosal lesions and may offer an alternative to surgical resection.

A prospective analysis of extended endoscopic mucosal resection for large rectal villous adenomas: an alternative technique to transanal endoscopic microsurgery

INTRODUCTION

Endoscopic mucosal resection is a safe resection tool for selected flat, sessile and lateral spreading tumours of the colon. Transanal microsurgical resection of select rectal neoplastic lesions is another accepted modality. Recent data suggests transanal microsurgery may have high complication rates. We conducted a prospective clinicopathological evaluation of an extended endoscopic mucosal resection technique for highly selected lesions of the rectum and assessed outcome data over a maximal 24-month period.

PATIENTS AND METHODS

Eighty-three patients with known rectal neoplastic lesions underwent chromoscopic colonoscopy and on-table staging using a high-frequency (12.5 MHz) mini-probe EUS by a single endoscopist. Patients with T2 or node positive disease were referred for surgery. Following extended endoscopic mucosal resection patients were followed-up at 3, 6, 12 and 24 months post 'index' resection with chromoscopic endoscopy and EUS. Procedural complications, recurrence rates and outcome data were collected.

RESULTS

Sixty-two patients fulfilled inclusion criteria. Median procedure time was 48 mins (range 32-126). Lateral spreading tumours (median diameter 30 mm; range 18-42 mm) and sessile lesions (median diameter 38 mm; range 25-86 mm) accounted for 19% and 81% of lesions, respectively. Ninety-seven percent of patients undergoing EMR were discharged within 6-h of procedure. Thirty-day re-admission and death rate was 0%. Bleeding complications occurred in 5/62 (8%) of patients with all achieving complete haemostasis using endo clips. None required transfusion. There were no procedural related complications or perforations. Overall 'cure' rate at a median follow-up of 16 months was 98%.

CONCLUSIONS

Extended endoscopic mucosal resection for rectal neoplastic lesions can achieve superior results to those of per-anal excision and trans-anal microsurgery with regard to complications and recurrence rates. Extended endoscopic mucosal resection may be an alternative therapeutic modality in selected patients.

Endoscopic morphological anticipation of submucosal invasion in flat and depressed colorectal lesions: clinical implications and subtype analysis of the kudo type V pit pattern using high-magnification-chromoscopic colonoscopy

OBJECTIVE

Focal submucosal invasive colorectal cancers (submucosa-sm1) can be managed by endoscopic mucosal resection (EMR) as local lymph node metastasis (LNM) are rare. Lesions are usually flat, depressed or mixed. In deeper vertical submucosal invasion (sm2-3) LNM rates exceed 10-15%. EMR within this group can be complicated by perforation, noncurative resection and may leave LNM untreated. It is therefore essential to differentiate accurately focal sm1 disease from submucosal sm2/3 disease. The aim of this study was to evaluate the relationship between the invasive type V pit pattern using high-magnification-chromoscopic-colonoscopy (HMCC) and submucosal invasive depth for flat and depressed colorectal lesions.

METHODS

Total colonoscopy was performed by a highly selected single endoscopist using the Olympus C240Z on 850 patients between January 2001 and July 2003. Kudo type V pits were identified using 0.05% crystal violet (CV) applied directly to the lesion using a steel tipped catheter. Type V pits were graded into class V(n)A-C as described by Nagata. Morphology was documented using the Japanese Research Society classification (JRSC). Histological sections, with reference to mucosal invasive characteristics, acquired using EMR or surgical excision were then compared with the pit pattern.

RESULTS

Fifty-one lesions showed a type V pit pattern. The kappa coefficient of agreement between pit the type V pit pattern and histologically confirmed submucosal invasion was 0.51 (95% CI). Following resection, 97% of lesions were correctly anticipated to have sm2 + invasion using pit type Vn(B) and Vn(C) as clinical indicators of invasive disease. Specificity was low at 50% with an accuracy of 78%.

CONCLUSIONS

The type V pit pattern is useful for the in vivo staging of submucosal invasive depth in flat and depressed colorectal lesions and is as sensitive as conventional 7.5 MHz EUS. There was a tendency to over-stage lesions and hence the technique is limited by its low overall specificity.

EMR of large sessile colorectal polyps

BACKGROUND

EMR optimizes histopathologic assessment of resected lesions. This study evaluated the outcome of EMR of large sessile colorectal polyps in terms of complications and recurrence.

METHODS

An uncontrolled prospective study was conducted of a cohort of 136 patients with sessile colorectal polyps referred for EMR. After submucosal injection, EMR was performed piecemeal by either snare polypectomy alone or with cap aspiration.

RESULTS

In 136 patients, a total of 139 sessile polyps were resected, 86 of which were in the right colon. Median polyps diameter was 20 mm in the right colon and 30 mm in the other colonic segments. Intraprocedure bleeding occurred after 15 polypectomies (10.8%) and was controlled endoscopically in all cases; there was no delayed bleeding. Post-polypectomy syndrome occurred in 5 patients (3.7%). There was no perforation. Invasive carcinoma was found in 17 sessile colorectal polyps, and surgery was performed in 10 of 17 cases. Follow-up colonoscopy in 93 patients without invasive carcinoma (96 polyps), over a median of 12.3 months, disclosed local recurrence of 21 adenomatous polyps (21.9%). Colonoscopic follow-up in 5 of the 7 patients, who had sessile colorectal polyps with invasive carcinoma and did not undergo surgery, disclosed no local recurrence.

CONCLUSIONS

EMR, including EMR with cap aspiration, is effective and safe for removal of sessile colorectal polyps throughout the colon.

The role of flat and depressed colorectal lesions in colorectal carcinogenesis: new insights from clinicopathological findings in high-magnification chromoscopic colonoscopy

High-magnification chromoscopic endoscopy is a new technique which has been recently introduced to the UK. This technology, initially pioneered by the Japanese in the 1980s, has changed our understanding of the pathogenesis of colorectal cancer and our subsequent therapeutic strategies aimed at the secondary prevention of cancer. Magnification colonoscopic techniques when combined with colonic chromoscopy (dye spraying of the colon) permit in vivo assessments of lesions at a magnification and resolution similar to a stereomicroscope. Furthermore, flat/depressed adenomas and cancers can be diagnosed with increasing frequency and new resection practices performed. This technique is known as endoscopic mucosal resection. As gastrointestinal endoscopists adopt these new techniques, close liaison with histopathologists is essential to provide the highest standards of diagnostic accuracy. The histopathologist also needs to be aware of the endoscopic findings when interpreting specimens and hence must understand new endoscopic terminologies and classification systems that accompany the introduction of new technologies and therapeutic techniques. This article describes the controversies relating to the flat and depressed colorectal lesion, where these new endoscopic technologies are ideally suited. It then provides a working description of high-magnification chromoscopic colonoscopy including the Japanese 'pit pattern' and morphological classification system-information which will be provided to histopathologists with specimens obtained by these new techniques. Finally, we describe the procedure of endoscopic mucosal resection, as the type and quality of specimens received for histopathological analysis will be highly influenced by these techniques.

Nonsurgical approaches to esophageal malignancy

Esophageal cancer remains one of the leading causes of cancer death worldwide. Patients generally present with progressive dysphagia, malnutrition, and weight loss. The diagnosis commonly involves radiologic studies and conventional esophagogastroduodenoscopy. Advances in endoscopic evaluation have allowed early detection of premalignant and malignant lesions. These techniques include chromoscopy, which can be performed in conjunction with high-resolution/magnification endoscopy, and fluorescent endoscopy. Such techniques as endoscopic ultrasound with dedicated echoendoscopes or high-frequency probes, positron emission tomography, optical coherence tomography, endoscopic magnetic resonance imaging, and tactile sensing may complement conventional imaging by CT to enhance staging accuracy. Because the majority of patients present with incurable disease at the time of diagnosis, nonsurgical approaches to their management have evolved. These include endoscopic mucosal resection, stenting, tumor ablation, and palliative chemoradiotherapy. The ablative techniques include argon plasma coagulator therapy, laser, and photodynamic therapy. For patients with early malignancies of the esophagus who are not surgical candidates, such techniques may be used with curative intent.

Gastric atrophy, metaplasia, and dysplasia: a clinical perspective

Gastric carcinoma of the intestinal type originates in dysplastic epithelium, which in turn develops in the milieu of atrophic gastritis and intestinal metaplasia. Cancers also may develop less often from gastric adenomatous polyps, which represent dysplastic epithelium arising in a raised lesion. The main causes of chronic atrophic gastritis and gastric atrophy are autoimmune due to pernicious anemia or chronic Helicobacter pylori infection. In the former condition, there is severe atrophy of the corpus (oxyntic mucosa), with the antrum being speared. In contrast, chronic atrophic gastritis consequent to H. pylori infection is a multifocal pangastritis, involving independent foci in the corpus and antrum of the stomach. For the most part, these clinical conditions are silent; the only manifestation of both these forms of chronic atrophic gastritis is cobalamin (vitamin B(12)) deficiency. In the case of the autoimmune gastritis of pernicious anemia, cobalamin deficiency results form the absence of intrinsic factor. When cobalamin deficiency occurs in patients with H. pylori-related gastritis, for the most part, it is because these patients have hypochlorhydria and are therefore unable to release cobalamin from its bound form in food. Patients may have advanced neuropsychiatric manifestations of cobalamin deficiency and yet not be anemic, have a normal blood smear, and even have serum cobalamin levels in the normal range. The condition may be identified by demonstrating elevated levels of homocysteine and methylmalonic acid. Intestinal metaplasia may be of the enteric (grade I), enterocolic (grade II), or colonic (grade III) type. Grade III intestinal metaplasia has traditionally been thought of as the most sinister variety, although the extent of atrophy and metaplasia may be a better marker for premalignancy than the mere identification of small areas of grade III intestinal metaplasia. Over the years, there has been much disagreement and a high degree of interrater variability, especially between Western and Japanese pathologists, as to the different grades of dysplasia and early gastric cancer. Recent consensus conferences at Vienna and Padova have resulted in better understanding of what constitutes these lesions, and it is hoped that in the near future agreement between pathologists will improve as a consequence. For the present, it is imperative that clinicians obtain second opinions from two or more expert pathologists on biopsy specimens before arriving at a diagnosis of either low- or high-grade dysplasia. The former histologic diagnosis is tantamount to subjecting the patient to endoscopic surveillance and the latter is tantamount to a decision regarding the resection of the lesion, both decisions being psychologically disturbing for patients. At this time, population screening for H. pylori is not recommended in Western countries, but most experts would agree that H. pylori should be eradicated if detected as part of the appropriate investigation of a clinical disorder such as dyspepsia. Certain other specific conditions may also be considered to be precancerous, such as the gastric remnant after a partial gastrectomy and the gastric mucosa in familial adenomatous polyposis syndrome and in familial Peutz-Jeghers syndrome and perhaps Ménétrier disease.

Endoscopic treatment of early gastroesophageal malignancy

With the routine use of endoscopy, gastroesophageal cancers, which were often diagnosed in the symptomatic and incurable state, are now being diagnosed at earlier stages. Treatment of early-stage upper gastrointestinal cancers has evolved tremendously. Endoscopic therapy has been employed for early-stage lesions in an attempt to avoid the high morbidity and mortality associated with current curative procedures such as esophagectomy. These new endoscopic techniques include endoscopic mucosal resection, photodynamic therapy, electrocoagulation, and laser therapy. Exciting and novel endoscopic therapeutic options in diagnosing and treating early gastroesophageal cancers are the focus of this review.