A new technique for endoscopic mucosal resection with an insulated-tip electrosurgical knife improves the completeness of resection of intramucosal gastric neoplasms

Endoscopic mucosal resection and endoscopic submucosal dissection for early gastric cancer: Current and original devices

Compared with endoscopic submucosal dissection (ESD), endoscopic mucosal resection (EMR) is easier to perform and requires less time for treatment. However, EMR has been replaced by ESD, because achieving en bloc resection of specimens > 20 mm in diameter is difficult with EMR. The technique of ESD was introduced to resect large specimens of early gastric cancer in a single piece. ESD can provide precise histological diagnosis and can also reduce the rate of recurrence, but has a high level of technical difficulty, and is consequently associated with a high rate of complications, a need for advanced endoscopic techniques, and a lengthy procedure time. To overcome disadvantages in both EMR and ESD, various advances have been made in submucosal injections, knives, other accessories, and in electrocoagulation systems.

Ease of early gastric cancer demarcation recognition: a comparison of four magnifying endoscopy methods

BACKGROUND AND AIM

Various techniques using magnifying endoscopy (ME) have been developed to enhance images of early gastric cancer (EGC) demarcations, which are often obscure. We investigated four ME methods to determine which is most effective in enhancing the recognition of EGC demarcations: conventional ME (CME), ME with narrow band imaging (NBI-ME), enhanced-magnification endoscopy with acetic acid (EME), and ME with NBI and acetic acid (NBI-EME).

METHODS

Thirty-seven successive patients having a total of 40 EGCs participated in the investigation. The endoscope was fixed and magnification images of EGC demarcations in each patient were recorded using four different ME methods (CME, NBI-ME, EME and NBI-EME). Eight experts and eight non-experts scored each of the four images of each lesion for ease of recognition of demarcation (1 to 4, with 4 being easiest).

RESULTS

The mean scores of expert and non-expert judges, respectively, for images acquired using each technique were: CME 1.23, 1.24; NBI-ME 2.61, 2.95; EME 2.62, 2.32 and NBI-EME 3.54, 3.50. There were significant differences between the mean scores for the four techniques (P < 0.0001) using one-way repeated-measures anova. In a Bonferroni's multiple comparison, the average scores (expert and non-expert) of images acquired using NBI-EME were significantly higher than those acquired using other methods; images acquired by NBI-ME or EME also scored significantly higher than those by CME. Non-experts also scored NBI-ME images significantly higher than CME and EME images.

CONCLUSIONS

Early gastric cancer demarcations were recognized most easily using NBI-EME, and more easily using EME or NBI-ME than CME.

Endoscopic submucosal dissection for superficial duodenal neoplasms

Endoscopic submucosal dissection (ESD) has emerged as a novel technique for achieving en bloc resection for superficial neoplasms limited to the mucosa. ESD was originally developed in Japan as a method of endoscopic resection of superficial gastric cancers. In our hospital, ESD has been used concurrently in other parts of the gastrointestinal tract, including the esophagus and colorectum from the beginning of its development. However, ESD in the duodenum is considered more challenging than other parts. From August 2005 to March 2008, a total of 15 superficial duodenal neoplastic lesions in 14 patients were treated with endoscopic resection. Of these, nine underwent ESD. We report our experience with duodenal ESD with a combination of ST hood and hook knife.

Endoscopic submucosal dissection for gastric submucosal tumor, endoscopic sub-tumoral dissection

Gastric submucosal tumor (SMT) is frequently found during screening endoscopy, but definitive diagnosis based on histological confirmation is relatively difficult. Even without accurate diagnosis before treatment, open or laparoscopic surgery is currently carried out to remove SMT. The purpose of this study was to demonstrate the feasibility of endoscopic submucosal dissection (ESD) in diagnostic treatment for submucosal tumor (SMT) of the stomach. Subjects in this case study comprised nine patients who had undergone ESD for gastric SMT. Before treatment, endoscopic ultrasonography was carried out in all cases to evaluate depth and origin of the SMT. Then ESD was only indicated for tumors of submucosal layer or muscularis mucosa origin. Using an endoscopic sub-tumoral dissection technique with a hook knife and a flex knife, local complete resections were achieved in all patients without severe complications. These results suggest the clinical benefits of ESD avoiding oversurgery for the diagnostic treatment of gastric SMT of the submucosal layer and muscularis mucosa origin.

Clinical outcomes of endoscopic submucosal dissection for undifferentiated early gastric cancer

BACKGROUND

Early gastric cancer (EGC) with undifferentiated histology has not been generally accepted as an indication for endoscopic treatment. This study was designed to evaluate the outcomes and clinicopathological factors associated with the complete resection of undifferentiated EGC using endoscopic submucosal dissection (ESD).

METHODS

A retrospective analysis of prospectively collected data was performed on consecutive patients who underwent ESD. Among the 456 EGCs treated using ESD at the Seoul National University Hospital, Seoul, Korea, between April 2005 and June 2008, 60 lesions (13.2%) were diagnosed as undifferentiated gastric cancer (poorly differentiated adenocarcinoma or signet ring cell carcinoma).

RESULTS

En bloc resection was performed in all lesions without significant complications. The size discrepancy between the pretreatment endoscopy and the resected specimen was significantly higher in undifferentiated EGCs than differentiated EGCs (p = 0.002). The complete resection rate was significantly lower for undifferentiated EGC (55%) cases than differentiated EGC cases (84.1%; p < 0.001). Independent risk factors for incomplete resection of undifferentiated EGC included tumor size >20 mm, submucosal invasion, and presence of ulceration. During a mean observation time of 16 months, no recurrence developed in any of the patients with undifferentiated EGCs thought to be completely resected by ESD.

CONCLUSIONS

ESD might be considered an alternative treatment modality in carefully selected cases of undifferentiated EGC.

Randomized controlled study of EMR versus endoscopic submucosal dissection with a water-jet hybrid-knife of esophageal lesions in a porcine model

BACKGROUND

Endoscopic submucosal dissection (ESD) seems to be more effective than EMR for curative resection of GI mucosal neoplasia. However, ESD is technically difficult, hazardous, and time consuming. New technologies may overcome these drawbacks.

OBJECTIVE

Our purpose was to compare a new simplified ESD technique with conventional EMR.

DESIGN

Prospective, randomized, and controlled trial in anesthetized pigs.

METHODS

A total of 25 esophageal areas with a diameter of 20 mm were marked with coagulation points in 6 pigs under general anesthesia. These lesions were then randomized to either EMR by use of the cap technique or ESD. Submucosal injection of saline solution was used for both methods. ESD was performed with a hybrid-knife (ESDH), which allows cutting and coagulation as well as a needleless, tissue-selective hydrodissection through an axial water-jet channel with a preselected pressure by using a high-pressure water-jet system (ErbeJet 2). Intraoperative bleedings were treated with hemostatic forceps.

MAIN OUTCOME MEASUREMENTS

A comparison of the rates of complete resection of the lesions, the number and the size of resected specimens, the complication rate, and the procedural duration.

RESULTS

Thirteen lesions were randomized to EMR and 12 to ESDH. ESDH achieved complete resection significantly more frequently than EMR (10/12 vs 6/13; P = .05). All ESDH resections were performed as a single piece, whereas a mean (SD) of 2.5 +/- 0.9 resections were needed for EMR (P < .05). The mean (SD) areas of the specimen were 3.63 +/- 1.20 cm(2) in the ESDH group and 1.83 +/- 0.78 cm(2) in the EMR group (P < .0001). ESDH was performed with a larger amount of fluid for injection and hydrodissection compared with EMR (78.1 +/- 32.8 mL vs 20.9 +/- 7.6 mL; P < .001). The procedural duration was longer for ESDH than for EMR (28.2 +/- 11.9 minutes vs 12.2 +/- 4.9 minutes; P < .001). ESDH and EMR caused bleedings in 6 of 12 and 5 of 13 of the cases (P = .09), respectively. Hemostasis could be achieved in all cases. There was no perforation in either group.

LIMITATIONS

Resection of artificial non-neoplastic lesions, small numbers, an animal trial.

CONCLUSIONS

ESDH achieves complete resection of esophageal lesions significantly more frequently with a fewer number of specimens than EMR. ESDH is more time consuming, but the procedural duration seems to be shorter than conventional ESD because there is no need for exchange of devices for injection and cutting. The easy use of water-jet-assisted repeated injections of fluids may explain why ESDH was as safe as EMRC.

Benefits of endoscopic submucosal dissection according to size and location of gastric neoplasm, compared with conventional mucosal resection

BACKGROUND AND AIMS

To clarify optimal therapeutic strategies for early gastric cancers without vestigial remnant or recurrence, we evaluated the benefits of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) according to tumor size and location.

METHODS

From January 2000 to December 2007, a total of 328 gastric lesions were treated using conventional EMR, while 572 lesions were treated by ESD. Patients who underwent surgery on the upper gastrointestinal tract before EMR or ESD were excluded from the study. We compared tumor size, location and rates of complete resection, curative resection, postoperative bleeding, perforation and local recurrence between EMR and ESD according to tumor situation.

RESULTS

Overall local complete resection rate (EMR, 64.2%; ESD, 95.1%) and overall curative resection rate (EMR, 59.5%; ESD, 82.7%) were significantly higher in ESD than in EMR. No significant differences were seen in complication rates between EMR and ESD. Local recurrence was detected in 13 lesions (4.0%) of the EMR group during follow up. In contrast, no local recurrence was detected in the ESD group. For lesions 5 mm or less in diameter, complete resection rate in the EMR group was not significantly inferior to that in the ESD group at any location. However, rates were overwhelmingly better in the ESD group than in the EMR group for lesions more than 5 mm in diameter, regardless of location.

CONCLUSION

We concluded that lesions exceeding 5 mm in diameter should be treated by ESD, although a high resection rate is obtained also with EMR for lesions of 5 mm or less in diameter.

Endoscopic submucosal dissection for gastric epithelial tumors: a multicenter study in Taiwan

BACKGROUND/PURPOSE

Endoscopic submucosal dissection (ESD) is an advanced endoscopic procedure to resect early gastric cancer (EGC). The purpose of this study was to determine the effectiveness and complications of ESD for gastric epithelial tumors in Taiwan.

METHODS

We retrospectively analyzed the efficacy and outcome of ESD in patients who received ESD for gastric epithelial tumors between June 2004 and August 2007.

RESULTS

A total of 70 patients with gastric epithelial tumors were treated by ESD. The mean age was 66.5 +/- 12.9 years (range, 35-84 years). The mean size of the gastric epithelial tumors was 1.85 +/- 0.81 cm. The mean size of resected specimens was 3.26 +/- 1.39 cm. The one-piece resection rate was 91.4% (64/70). The median operation time was 92.4 minutes. The complicating bleeding and perforation rates were 5.7% (4/70) and 4.3% (3/70), respectively. Emergency surgery was performed for three patients with perforations. The local recurrence rate of gastric cancer was 2.8%. Except for one patient who died of congestive heart failure and another who died of stroke, the remaining 68 patients (97.1%) survived.

CONCLUSION

ESD is a promising local curative treatment option for EGC in Taiwan but it still carries risks of perforation and bleeding. The education and learning curve of endoscopists will improve the outcome of this procedure.

The modern treatment of early gastric cancer: our experience in an Italian cohort

BACKGROUND

Endoscopic submucosal dissection (ESD) has been developed as treatment for early gastric cancer (EGC) by Japanese authors. However, there are no reports about its possible implementation in the Western setting. The aim of the present work is to determine the safety and efficacy of the endoscopic treatments for EGC in an Italian cohort.

METHODS

Forty-five patients for a total of 48 gastric lesions were enrolled in the study. Thirty-six EMR procedures were performed with the strip biopsy technique using a double-channel endoscope. En bloc resection refers to resection in one piece, while piecemeal refers to resections in which the lesion was removed in multiple fragments. A total of 12 ESD were performed and completed with IT knife. We define as curative treatment lateral and vertical margins of the resected specimens free of cancer and repeat endoscopic finding of no recurrent disease.

RESULTS

Out of 36 EMR procedures, 10 were piecemeal resections (28%), while 26 were en bloc (72%). ESD led to en bloc resection in 11/12 cases (92%). Histological assessment of curability in the EMR group was achieved in 56% of the cases, and in 92% of the ESD group. Mean follow-up period was 31 months (range: 12-71 months). There was no local recurrence or distant metastasis in the curative group patients.

CONCLUSIONS

These results seem to confirm the safety and the clinical efficacy of the ESD procedure in the Western world too.

Clinical outcomes of endoscopic submucosal dissection (ESD) for treating early gastric cancer: comparison with endoscopic mucosal resection after circumferential precutting (EMR-P)

BACKGROUND

To achieve en bloc resection for large lesions, endoscopic mucosal resection after circumferential precutting and endoscopic submucosal dissection techniques have been developed.

AIM

To compare endoscopic submucosal dissection with endoscopic mucosal resection after circumferential precutting in terms of the clinical efficacy and safety.

PATIENTS AND METHODS

346 consecutive patients underwent their first endoscopic mucosal resection after circumferential precutting (103 patients) or endoscopic submucosal dissection (243 patients) for early gastric cancer and their clinical outcomes were compared.

RESULTS

For early gastric cancer >or=20mm endoscopic submucosal dissection group demonstrated significantly higher en bloc resection and en bloc plus R0 resection rate compared with endoscopic mucosal resection after circumferential precutting group. For early gastric cancer with size of 10-19 mm, endoscopic submucosal dissection group also showed significantly higher en bloc resection rate. For early gastric cancer <20mm, however, en bloc plus R0 resection rate for endoscopic mucosal resection after circumferential precutting group was comparable to that for endoscopic submucosal dissection group. In case of R0 resection of intramucosal differentiated cancer, neither group showed local recurrence during the median 29 and 17 months of follow-up. Two groups did not show significant difference in the bleeding or perforation rates.

CONCLUSION

For early gastric cancer <20mm endoscopic mucosal resection after circumferential precutting may be considered as an alternative choice to endoscopic submucosal dissection. However, for early gastric cancer >or=20mm endoscopic submucosal dissection should be considered as the first choice for treating early gastric cancer.

Endoscopic submucosal dissection of early cancers, flat adenomas, and submucosal tumors in the gastrointestinal tract

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) is a promising technique in the treatment of large premalignant and early malignant gastrointestinal lesions. In contrast to Japan and Asian countries, few data are available from Western countries. The objective of this study was to assess the feasibility of ESD in a European center, with special regard for the success rate and learning curve.

METHODS

Over a 4-year-period, 82 epithelial or submucosal lesions were referred for ESD. Seventy-one ESDs were performed (51 gastric, 17 rectal, 2 esophageal, and 1 duodenal). Resection rates, procedure times, specimen sizes, complications, and recurrences were noted. The mean follow-up period was 15 months.

RESULTS

Specimen size increased significantly (P < .05) and procedural duration decreased significantly (P < .005) over time. En bloc resection rates and R0 en bloc resection rates were 77.1% and 65.7%, respectively, in the first half of the study and increased to 86.1% and 72.2%, respectively, in the second half (P = NS). No recurrence was observed after R0 en bloc resection whereas the recurrence rate was 38.5% after piecemeal resections (P < .001). Two perforations in the first series were treated by surgery; 2 other perforations, 8 minor bleedings, and 2 pyloric stenoses were treated endoscopically.

CONCLUSIONS

ESD is technically feasible and shows promising results in this German single-center-study. ESD is time consuming and difficult but shows a learning curve resulting in a decrease of the procedural duration over time. R0 en bloc resection is mostly possible and can avoid the risk of local recurrence.

A novel device for endoscopic submucosal dissection, the Fork knife

AIM: To introduce and evaluate the efficacy and technical aspects of endoscopic submucosal dissection (ESD) using a novel device, the Fork knife.

METHODS: From March 2004 to April 2008, ESD was performed on 265 gastric lesions using a Fork knife (Endo FS^®) (group A) and on 72 gastric lesions using a Flexknife (group B) at a single tertiary referral center. We retrospectively compared the endoscopic characteristics of the tumors, pathological findings, and sizes of the resected specimens. We also compared the en bloc resection rate, complete resection rate, complications, and procedure time between the two groups.

RESULTS: The mean size of the resected specimens was 4.27 ± 1.26 cm in group A and 4.29 ± 1.48 cm in group B. The en bloc resection rate was 95.8% (254/265 lesions) in group A and 93.1% (67/72) in group B. Complete ESD without tumor cell invasion of the resected margin was obtained in 81.1% (215/265) of group A and in 73.6% (53/72) of group B. The perforation rate was 0.8% (2/265) in group A and 1.4% (1/72) in group B. The mean procedure time was 59.63 ± 56.12 min in group A and 76.65 ± 70.75 min in group B (P < 0.05).

CONCLUSION: The Fork knife (Endo FS^®) is useful for clinical practice and has the advantage of reducing the procedure time.

Risk factors associated with local recurrence of early gastric cancers after endoscopic submucosal dissection

BACKGROUND

Although endoscopic submucosal dissection (ESD) is expected to reduce the local recurrence of gastric cancers, we still experience cases of recurrence after an ESD.

OBJECTIVE

To characterize clinical and pathologic features of cases with local recurrence of early gastric cancer after an ESD.

DESIGN

A prospective cohort study.

SETTING AND PATIENTS

A total of 306 patients with gastric cancers removed by ESD at Okayama University Hospital and Tsuyama Central Hospital between March 2001 and December 2005 were enrolled.

INTERVENTION

ESD.

MAIN OUTCOME MEASUREMENT

Local recurrence.

RESULTS

The incidence of a complete en bloc resection was 80.4% when pathologically evaluated. Within a median follow-up period of 26 months (12-64 months), a local recurrence was found in 7 cases, all of which had been declared incomplete resections. One patient underwent a second ESD, and the remaining 6 underwent a surgical resection. All removed lesions were mucosal cancers. No lymph-node metastases were found in patients with a surgical resection. There was a significant correlation between the incidence of an incomplete resection and that of a local recurrence (P < .0001). Among the clinical characteristics, tumor size (>30 mm vs <20 mm; odds ratio [OR] 16 mm [95% CI, 2.0-130 mm]) and tumor location (upper vs middle or lower; OR 7.6 [95% CI, 1.3-45]) were identified as factors that were significantly associated with the incidence of a local recurrence.

LIMITATION

Short follow-up duration.

CONCLUSIONS

The incidence of a local recurrence was strongly associated with that of an incomplete resection. The frequency of a local recurrence also showed significant correlations with the tumor size and location within the stomach.

Endoscopic resection of early oesophageal and gastric neoplasia

In the last decades, endoscopic treatment of early neoplastic lesions in the oesophagus and stomach has evolved as a valid and less invasive alternative to surgical resection. Endoscopic resection (ER) is the cornerstone of endoscopic therapy. Apart from the curative potential of ER, by removing neoplastic lesions, ER may also serve as a diagnostic tool. The relatively large tissue specimens obtained with ER enable accurate histological staging of a lesion, allowing for optimal decision making for further patient management. ER was pioneered in Japan, mainly for the resection of gastric lesions and squamous oesophageal neoplasia, and also Western countries have been increasingly implementing ER in the treatment of early gastro-oesophageal neoplasia, mostly associated with Barrett oesophagus. In this review we will give an overview of the different techniques that have been developed and modified for ER of early gastro-oesophageal neoplasia, and we will discuss the indications for ER in the oesophagus and stomach.

Chromoendoscopy with indigo carmine dye added to acetic acid in the diagnosis of gastric neoplasia: a prospective comparative study

BACKGROUND

Conventional endoscopy and chromoendoscopy with indigo carmine dye are usually performed for recognizing adequate tumor-negative lateral margins for successful endoscopic resection of gastric neoplasia. However, chromoendoscopy with indigo carmine dye added to acetic acid has not been used for this purpose.

OBJECTIVE

Our purpose was to compare the diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid with that of conventional endoscopy and chromoendoscopy with indigo carmine dye or acetic acid alone.

DESIGN

Prospective study.

SETTING

Social Insurance Funabashi Central Hospital.

PATIENTS

Forty-seven consecutive patients (53 lesions) with early gastric cancer and gastric adenomas who underwent endoscopic submucosal dissection (ESD) from April 2006 to July 2007 were studied.

INTERVENTIONS

All the lesions were examined by the endoscopic modalities before ESD, and the resected specimens were analyzed histopathologically.

MAIN OUTCOME MEASUREMENTS

Two endoscopists independently evaluated the diagnostic performance of each image in terms of recognition of tumor borders with reference to macroscopic and histopathologic findings of resected specimens. We also conducted a substudy to assess interobserver variability.

RESULTS

There was good interobserver agreement between the 2 endoscopists in this study (kappa index = 0.764). The diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid was significantly greater than that of any of the other modalities (vs each: P < .005).

CONCLUSIONS

The diagnostic performance of chromoendoscopy with indigo carmine dye added to acetic acid was better compared with conventional endoscopy and chromoendoscopy by using only indigo carmine dye or acetic acid. The applicability of this method for gastric neoplasia merits further investigation.

Predictive factors for lymph node metastasis in poorly differentiated early gastric cancer and their impact on the surgical strategy

AIM: To identify the predictive clinicopathological factors for lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC) and to further expand the possibility of using endoscopic mucosal resection (EMR) for the treatment of poorly differentiated EGC.

METHODS: Data were collected from 85 poorly-differentiated EGC patients who were surgically treated. Association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses.

RESULTS: Univariate analysis showed that tumor size (OR = 5.814, 95% CI = 1.050 - 32.172, P = 0.044), depth of invasion (OR = 10.763, 95% CI = 1.259 - 92.026, P = 0.030) and lymphatic vessel involvement (OR = 61.697, 95% CI = 2.144 - 175.485, P = 0.007) were the significant and independent risk factors for LNM. The LNM rate was 5.4%, 42.9% and 50%, respectively, in poorly differentiated EGC patients with one, two and three of the risk factors, respectively. No LNM was found in 25 patients without the three risk factors. Forty-four lymph nodes were found to have metastasis, 29 (65.9%) and 15 (34.1%) of the lymph nodes involved were within N1 and beyond N1, respectively, in 12 patients with LNM.

CONCLUSION: Endoscopic mucosal resection alone may be sufficient to treat poorly differentiated intramucosal EGC (≤ 2.0 cm in diameter) with no histologically-confirmed lymphatic vessel involvement. When lymphatic vessels are involved, lymph node dissection beyond limited (D1) dissection or D1+ lymph node dissection should be performed depending on the tumor location.

Endoscopic submucosal dissection for gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) is an advanced technique of therapeutic endoscopy for superficial gastrointestinal neoplasms. Three steps characterize it: injecting fluid into the submucosa to elevate the lesion, cutting the surrounding mucosa of the lesion, and dissecting the submucosa beneath the lesion. The ESD technique has rapidly permeated in Japan for treatment of early gastric cancer, due to its excellent results of en-bloc resection compared to endoscopic mucosal resection (EMR). Although there is still room for improvement to lessen its technical difficulty, ESD has recently been applied to esophageal and colorectal neoplasms. Favorable short-term results have been reported, but the application of ESD should be well considered by three aspects: (1) the possibility of nodal metastases of the lesion, (2) technical difficulty such as location, ulceration and operator’s skill, and (3) organ characteristics.

Treatment of gastric remnant cancer post distal gastrectomy by endoscopic submucosal dissection using an insulation-tipped diathermic knife

AIM: To evaluate the effectiveness of endoscopic submucosal dissection using an insulation-tipped diathermic knife (IT-ESD) for the treatment of patients with gastric remnant cancer.

METHODS: Thirty-two patients with early gastric cancer in the remnant stomach, who underwent distal gastrectomy due to gastric carcinoma, were treated with endoscopic mucosal resection (EMR) or ESD at Sumitomo Besshi Hospital and Shikoku Cancer Center in the 10-year period from January 1998 to December 2007, including 17 patients treated with IT-ESD. Retrospectively, patient backgrounds, the one-piece resection rate, complete resection (CR) rate, operation time, bleeding rate, and perforation rate were compared between patients treated with conventional EMR and those treated with IT-ESD.

RESULTS: The CR rate (40% in the EMR group vs 82% in the IT-ESD group) was significantly higher in the IT-ESD group than in the EMR group; however, the operation time was significantly longer for the IT-ESD group (57.6 ± 31.9 min vs 21.1 ± 12.2 min). No significant differences were found in the rate of underlying cardiopulmonary disease (IT-ESD group, 12% vs EMR group, 13%), one-piece resection rate (100% vs 73%), bleeding rate (18% vs 6.7%), and perforation rate (0% vs 0%) between the two groups.

CONCLUSION: IT-ESD appears to be an effective treatment for gastric remnant cancer post distal gastrectomy because of its high CR rate. It is useful for histological confirmation of successful treatment. The long-term outcome needs to be evaluated in the future.

Chemically assisted endoscopic mechanical submucosal dissection by using mesna

BACKGROUND

A class of thiol compounds, mesna (sodium-2-mercaptoethanesulfonate), has been used to facilitate tissue dissection in surgical fields.

OBJECTIVES

To evaluate the technical feasibility and efficacy of chemically assisted endoscopic mechanical submucosal dissection (CAEMSD) by using mesna.

DESIGN

An in vivo controlled blind trial by using porcine models.

SETTINGS

Nonsurvival study in an animal laboratory.

INTERVENTIONS

Six pigs were studied. Mucosal targets of about 2 cm (estimated) for treatment were created with a circle of cauterized spots along the greater curvature of the gastric body and the antrum. A mesna solution or the control hydroxypropyl methylcellulose solution was submucosally injected. The target mucosa was mechanically isolated with balloon dissection and removed by circumferential incision with a hook-knife inserted into the submucosal space. Necropsy and mucosal specimens from both groups were examined by histology.

RESULTS

En bloc resection of the target was achieved in all 8 attempts of the mesna group and in 7 of 8 attempts of the control group. Use of mesna significantly reduced tissue resistance to the initial balloon-catheter insertion into the submucosa and the technical difficulty of subsequent submucosal balloon dissection by using a subjective grading system (P < .05). There was no difference in histology between both groups.

CONCLUSIONS

CAEMSD is a unique methodology to facilitate mucosal resection.

Application of metal hemoclips for closure of endoscopic mucosal resection-induced ulcers of the stomach to prevent delayed bleeding

BACKGROUND

Bleeding is a major complication of endoscopic mucosal resection (EMR). This study investigated whether the use of metal hemoclips to close EMR-induced ulcers after gastric EMR was effective in preventing delayed bleeding.

METHODS

This single-center study retrospectively examined the records for 150 lesions of 140 consecutive patients (107 men and 33 women) with a mean age of 61 years (range, 38-81 years) who underwent EMR. For 60 patients, moderate to severe immediate bleeding occurred during the procedure, and the ulcers had been closed using metal hemoclips (clip group). In the remaining 90 cases, the immediate bleeding was absent or mild, and hemoclips were not used (nonclip group). Postprocedure bleeding (delayed bleeding) was analyzed.

RESULTS

Overall, delayed bleeding occurred with 14 (9.3%) of the 150 lesions. Delayed bleeding occurred less frequently in the clip group (2 of 60 lesions; 3.3%) than in the nonclip group (12 of 90 lesions; 13.3%; p = 0.04). Of the 60 clip group ulcers, 37 (62%) were completely closed, and none showed delayed bleeding. The median number of hemoclips used for ulcer closure was 10 (range, 4-22), and the median time for ulcer closure was 14 min (range, 4-40 min).

CONCLUSIONS

Prophylactic closure of gastric EMR-induced ulcers with hemoclips reduced delayed bleeding.

Optimal band imaging system can facilitate detection of changes in depressed-type early gastric cancer

BACKGROUND

The endoscopic diagnosis of depressed-type early gastric cancers is difficult because these cancers manifest as subtle changes in color and shape. The newly developed optimal band imaging (OBI) system can reconstruct the best spectral images derived from ordinary endoscopic images and enhances the mucosal surface without the use of dyes. This imaging technique is based on narrowing the bandwidth of conventional image arithmetically by using spectral estimation technology.

OBJECTIVE

Evaluation of the usefulness of the OBI system for identifying the demarcation line of depressed-type early gastric cancers.

DESIGN

Prospective study.

SETTING

Jichi Medical University in Japan.

PATIENTS

Twenty-seven cases with depressed-type early gastric cancer.

MAIN OUTCOME MEASUREMENT

Comparative study for the success rate of identifying the demarcation line of depressed-type early gastric cancer by using optimal band images and conventional endoscopic images.

RESULTS

Demarcation of the depressed-type early gastric cancer was easily identified by optimal band images without magnification in 26 of 27 cases (96%), because distinct demarcation was observed endoscopically between the reddish images of the cancerous lesion and the yellowish images of the surrounding noncancerous area. With 40-fold magnification of optimal band images, the demarcation was also clearly recognized in all cases. Medical students could point out the demarcation line with significantly greater accuracy by observing the new nonmagnified optimal band images than by the conventional images (P< .0001).

LIMITATION

Small sample size.

CONCLUSIONS

The new contrasting images of the OBI system can delineate the depressed-type early gastric cancer more easily than conventional endoscopy.

Endoscopic submucosal dissection for early gastric cancers: experience from a new endoscopic center in Taiwan

GOAL

To evaluate the efficacy of endoscopic submucosal dissection (ESD) for early gastric cancers (EGCs) at a new endoscopic center.

BACKGROUND

ESD is a novel technique that can facilitate en-bloc resection of EGCs, but seldom reported outside Japan.

STUDY

A total of 25 consecutive patients (25 lesions) underwent ESD from June 2004 to March 2006. Patients were divided into 2 groups: group A underwent ESD from June 2004 to May 2005 (introduction stage) and group B from June 2005 to March 2006. The following data were obtained: tumor size, tumor location, operative time, and major complication.

RESULTS

The complete resection was achieved in 20 lesions (success rate 80%). Four out of 10 lesions from group A were removed by conventional endoscopic mucosal resection (EMR) piecemeally after ESD failure. Conversely, 14 patients from group B (n=15) were resected by ESD en-bloc (success rate 93.3%). One patient with microscopic residual tumor after ESD was further treated by surgical resection. The time required for resection was significantly longer in group A when compared with group B (130.5 min vs. 81.5 min, P<0.05). Postoperative complication rate between the 2 groups were similar. One patient with piecemeal EMR recurred in follow-up, and was further treated successfully by EMR.

CONCLUSIONS

ESD is an ideal method for EGC treatment, but it may result in a risk of complication. The complete resection rate can be improved by endoscopist's experience. Sophisticated endoscopic hemostasis and clipping skills are essential prior ESD procedures. Conventional EMR techniques are also obligatory during the beginning period.

A prospective randomized trial of either famotidine or pantoprazole for the prevention of bleeding after endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) has been reported to have a higher bleeding rate than conventional methods. However, there are few reports on whether a proton pump inhibitor or a histamine2-receptor antagonist is the more effective treatment for preventing bleeding after ESD. In a prospective trial, patients undergoing ESD due to gastric adenoma or adenocarcinoma were randomly assigned to pantoprazole or famotidine. Both drugs were given intravenously for the first 2 days, thereafter by mouth. Eighty-five in the pantoprazole group and 79 in the famotidine group were included for analysis. Primary outcome measure was the delayed bleeding rate. Clinical characteristics were not different between the two groups. The delayed bleeding rate was significantly lower in the pantoprazole group compared with the famotidine group (3.5% vs. 12.7%, p=0.031). On multivariate analysis, the preventive use of pantoprazole (relative hazard: 0.220, 95% CI: 0.051- 0.827, p=0.026) and the specimen size (> or =34 mm, relative hazard: 4.178, 95% CI: 1.229-14.197, p=0.022) were two independent factors predictive of delayed bleeding. There were no significant differences in en bloc and complete resection rate between the two groups. In conclusion, pantoprazole is more effective than famotidine for the prevention of delayed bleeding after ESD.

Risk factors for lymph node metastasis in undifferentiated early gastric cancer

BACKGROUND

Endoscopic surgery has not been accepted as a curative treatment for intramucosal undifferentiated early gastric cancer (EGC). The purpose of this study was to evaluate the predictive factors of lymph node metastasis and explore the possibility of using endoscopic surgery for undifferentiated EGC.

METHODS

We retrospectively analyzed 646 patients with undifferentiated EGC who had undergone gastrectomy with D2 lymphadenectomy from January 2000 to March 2005. We used univariate and multivariate analysis to identify clinicopathological features that were predictive factors for lymph node metastasis.

RESULTS

The incidence of lymph node metastasis was 4.2% in intramucosal and 15.9% in submucosal undifferentiated EGC. Multivariate analysis revealed that submucosal invasion, larger tumor size (greater than 2 cm), and presence of lymphovascular invasion (LVI), were significantly associated with lymph node metastasis in patients with undifferentiated EGC. Tumor size and LVI were independent risk factors for lymph node metastasis in cases of intramucosal EGC. Lymph node metastasis was found in only one patient (0.5%) who had neither of the two risk factors for intramucosal EGC.

CONCLUSION

Complete endoscopic resection may be acceptable as a curative treatment for intramucosal undifferentiated EGC when the tumor size is less than or equal to 2 cm, and when LVI is absent in the postoperative histological examination. Radical gastrectomy should be recommended if LVI or unexpected submucosal invasion is present.

AC, Mota OMD. Endoscopic mucosal resection of early gastric cancer: initial experience with two technical variants

BACKGROUND: When performed in carefully selected cases, the endoscopic treatment of early gastric cancer yields results which are comparable to the conventional surgical treatment, but with lower morbidity and mortality and better quality of life. Several technical options to perform endoscopic mucosal resection have been described and there is a large amount of accumulated experience with this procedure in eastern countries. In western countries, particularly in Brazil, technical limitations associated with the small number of cases of early gastric cancer reflect the little experience with this therapeutic mode. AIM: This study was carried out in order to assess the indications, pathological results and morbidity of a series of endoscopic mucosal resections using two technical variants in addition to investigating the safety and feasibility of the method. METHODS: Individuals with well-differentiated early gastric adenocarcinomas with up to 30 mm in diameter without scar or ulcer underwent endoscopic treatment. Two variants of the strip biopsy technique were used. The pathological study assessed the depth of the vertical invasion, lateral and basal margins as well as angio-lymphatic invasion. RESULTS: Thirteen tumors in 12 patients were resected between June 2002 and August 2005. The most common macroscopic types were IIa and IIa + IIc. Tumor size ranged from 10 to 30 mm (mean = 16.5 mm). En bloc resection was carried out in nine patients. Angio-lymphatic invasion was not observed; however, submucosal invasion was found in two cases. In four cases, the lateral margin was involved. Perforation occurred in two patients who then received conservative treatment. CONCLUSION: The relatively small series presented here suggests that the method is safe and feasible. Appropriate patient selection is the most important criteria. Long follow-up is required after treatment due to the risk of relapse.

Treatment of over 20 mm gastric cancer by endoscopic submucosal dissection using an insulation-tipped diathermic knife

AIM: To evaluate the effectiveness of endoscopic submucosal dissection using an insulation-tipped diathermic knife (IT-ESD) for the treatment of patients with over 20 mm early gastric cancer (EGC).

METHODS: A total of 112 patients with over 10 mm EGC were treated with IT-ESD at Sumitomo Besshi Hospital and Shikoku Cancer Center in the 5 year period from January 2002 to December 2006, including 40 patients with over 20 mm EGC. We compared patient backgrounds, the one-piece resection rate, complete resection (CR) rate, operation time, bleeding rate, perforation rate between patients with over 20 mm EGC [over 20 mm group (21-40 mm)] and the remaining patients (under 20 mm group).

RESULTS: We found no significant difference in the rate of underlying cardiopulmonary disease (over 20 mm group vs under 20 mm group, 5.0% vs 5.6%), one-piece resection rate (95% vs 96%), CR rate (85% vs 89%), operation time (72.3 min vs 66.5 min), bleeding rate (5% vs 4.2%), and perforation rate (0% vs 1.4%) between the 2 groups. Three patients in each group had submucosal invasion and two in each groups underwent additional surgery.

CONCLUSION: There was no significant difference in the outcome resulting from IT-ESD between the 2 groups. Our study proves that IT-ESD is a feasible treatment for patients with over 20 mm mucosal gastric cancer although the long-term outcome should be evaluated in the future.

Novel techniques and instrumentation for EMR, ESD, and full-thickness endoscopic luminal resection

Endoscopic intervention is evolving into an established therapeutic alternative for small superficial lesions, and an eventual application for en bloc resection of large lesions, deeper layers, and a reliable access to lesions outside of the gastrointestinal wall. Although further developmental and clinical evaluation is necessary, we believe endoscopic resection by the submucosal route and by full-thickness approaches will replace standard surgical procedures in the next several years.

Endoscopic submucosal dissection with insulated-tip knife for large mucosal early gastric cancer: a feasibility study (with videos)

BACKGROUND

According to clinicopathologic studies, differentiated-type mucosal early gastric cancers without ulcer or ulcer scar have little risk of lymph-node metastasis, irrespective of tumor size. However, patients with large mucosal early gastric cancer have been subjected to surgery because conventional EMR methods could not resect large tumors en bloc.

OBJECTIVE

To evaluate the feasibility and the efficacy of endoscopic submucosal dissection for treatment of early gastric cancers larger than 3 cm in diameter.

DESIGN

Case series study.

SETTING

Referral cancer center.

PATIENTS

A total of 30 consecutive patients were enrolled with the following characteristics: diagnosis of differentiated-type early gastric cancer larger than 3 cm, lack of ulcerative change, no endoscopic evidence for submucosal invasion, and no evidence of lymph-node or distant metastasis (22 men and 8 women; median age, 69 years; median tumor size, 40 mm).

INTERVENTIONS

Tumors were resected by endoscopic submucosal dissection with an insulated-tip knife.

MAIN OUTCOME MEASUREMENTS

Complete resection, complication rate, and operation time.

RESULTS

Complete resection was obtained in 23 of 30 cases (77%). Complications included hemorrhage (n=4), perforation (n=1), and pyloric stenosis (n=1), but no severe complications occurred that required surgery or that led to major morbidity. Complete resection and complication rates improved in the last 10 cases (90% and 0%, respectively), though operation time was not shortened.

LIMITATIONS

Small sample size and lack of controls.

CONCLUSIONS

Endoscopic submucosal dissection when using the insulated-tip knife is feasible and efficacious for selected patients with mucosal early gastric cancer larger than 3 cm.

Combined laparoscopic endoscopic procedures

The combination of laparoscopy and flexible endoscopy has expanded the minimally invasive approaches to both benign and malignant gastrointestinal disease. This article reviews the current applications of combined approaches to gastric, colonic, and pancreatic pathology.

Advantages of endoscopic submucosal dissection over conventional endoscopic mucosal resection

BACKGROUND

Endoscopic mucosal resection is an established method for treating intramucosal gastric neoplasms. Conventional endoscopic mucosal resection has predominantly been performed using strip biopsy, but local recurrence sometimes occurs due to such piecemeal resection. Endoscopic submucosal dissection has recently been performed in Japan using new devices such as an insulation-tip diathermic knife. The efficacy and problems associated with endoscopic submucosal dissection were evaluated by comparison with conventional endoscopic mucosal resection.

METHODS

Treatment consisted of conventional endoscopic mucosal resection for 48 lesions from January 1999 to October 2002, and endoscopic submucosal dissection for 59 lesions from November 2002 to June 2005. Endoscopic submucosal dissection was performed using an insulation-tip diathermic knife and flex and hook knives, as appropriate.

RESULTS

For lesions >or=11 mm in size, en bloc resection rates were significantly higher with endoscopic submucosal dissection than with conventional endoscopic mucosal resection, but treatment time was significantly longer. En bloc resection rates were higher with endoscopic submucosal dissection than with conventional endoscopic mucosal resection in all areas. Treatment of lesions in the upper one-third of the stomach took a long time using endoscopic submucosal dissection, and intraoperative bleeding was frequent. However, en bloc resection rates and intraoperative bleeding with endoscopic submucosal dissection were improved using various knives.

CONCLUSIONS

Endoscopic submucosal dissection can take a long time, but is superior to conventional endoscopic mucosal resection for treating intramucosal gastric neoplasms.

Large early gastric cancers treated by endoscopic submucosal dissection with an insulation-tipped diathermic knife

It is difficult to remove a large early gastric cancer (> or = 3 cm) in one-piece resection using conventional endoscopic mucosal resection. We tried to use an insulation-tipped (IT) diathermic knife to dissect these lesions. IT-endoscopic submucosal dissection (ESD) was performed in four aging patients with gastric malignancy. All lesions could be removed in one-piece resection by IT-ESD, although three of them exhibited remarkable fibrosis and ulceration. Three cases experienced curative treatment with IT-ESD after the pathologic evaluation, but it was not curative in one case because the pathology showed angiolymphatic invasion. This patient refused additional surgery in consideration of existing major systemic diseases. At 3 months to 1 year of follow-up, endoscopy showed no evidence of residual cancer. IT-ESD is effective in the treatment of large early gastric cancer and is an alternative treatment for early gastric cancer patients who are at risk for major operation.

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.

Resection area of 15 mm as dividing line for choosing strip biopsy or endoscopic submucosal dissection for mucosal gastric neoplasm

BACKGROUND

Endoscopic mucosal resection (EMR) is effective treatment for mucosal gastric neoplasm. Endoscopic submucosal dissection (ESD), a novel EMR method, has been reported to enable en bloc resection more frequently than conventional EMR methods such as strip biopsy (SB). However, ESD requires more time than SB. A small lesion can be resected en bloc and effectively treated with SB.

GOAL

To evaluate using a 15 mm resection area as the dividing line between SB and ESD prospectively.

STUDY

SB was applied for resection area less than 15 mm (SB group) and ESD for 15 mm or larger resection (ESD group). We compared characteristics of lesions and outcomes of EMR between the 2 groups.

RESULTS

Ninety lesions were prospectively assigned to SB group (36 lesions) and ESD group (54 lesions). The average neoplasm size was 9.0+/-3.9 mm in the SB group and 19.1+/-11.3 mm in the ESD group (P<0.01). The average resection time was 11.7+/-5.8 minutes in the SB group and 128.9+/-102.8 minutes in the ESD group (P<0.01). The complete resection rate was 91.6% in the SB group and 83.3% in the ESD group (P=0.25). The complication rate was not significantly different between SB group and ESD group (11.1% vs. 16.7%, P=0.12). During follow-up (median 23+/-5 mo), 1 patient in each group, who had piecemeal resection at original EMR had recurrent neoplasm.

CONCLUSIONS

Gastric mucosal neoplasms which require only small (<15 mm) resection can be treated with SB, as effectively as with ESD.

Endoscopic therapy of dysplasia and early-stage cancers of the esophagus

Endoscopic treatments have become a viable alternative for some patients with early-stage esophageal neoplasia. Although esophagectomy remains the standard of care for high-grade dysplasia and superficial cancers, surgical morbidity and mortality may deter patients who are medically unfit or reluctant to undergo surgery. Photodynamic therapy (PDT) and endoscopic mucosal resection (EMR) are the best-studied nonsurgical approaches at present. PDT has been reported to eradicate high-grade dysplasia (HGD) and early Barrett's cancers at rates ranging from 75% to 100% and 17% to 100%, respectively, and a recent randomized controlled trial confirmed that PDT may prevent progression of HGD to cancer. Complete remission rates greater than 90% have also been reported with EMR and other mucosa-ablating interventions, although recurrence rates necessitate close endoscopic surveillance and retreatment in some patients. In addition to PDT and EMR, several emerging endoscopic treatment options for superficial esophageal neoplasia may provide attractive alternatives to surgery.

A pilot study to assess the safety and efficacy of carbon dioxide insufflation during colorectal endoscopic submucosal dissection with the patient under conscious sedation

BACKGROUND

Endoscopic submucosal dissection (ESD) is accepted as one of the treatments for en bloc resection of large superficial colorectal lesions. This procedure is performed by using air insufflation, is time consuming, and is associated with severe abdominal discomfort. The safety and efficacy of carbon dioxide (CO(2)) insufflation during colonoscopy already has been assessed in some trials.

OBJECTIVE

To assess the safety and efficacy of CO(2) insufflation instead of air insufflation during colorectal ESD with the patient under conscious sedation.

DESIGN

A case-control series with a historical control.

PATIENTS

A total of 35 consecutive patients were enrolled in this study. Another 35 consecutive patients who previously received colorectal ESDs by using air insufflation were included as a historical control.

INTERVENTIONS

Arterial partial pressure of CO(2) (pCO(2)) was measured before and after each procedure with the total dose of midazolam used as an index of abdominal discomfort.

MAIN OUTCOME MEASUREMENTS AND RESULTS

The mean (standard deviation [SD]) operation time was 90 +/- 57 minutes in the CO(2) group and 100 +/- 80 minutes in the control group (not significant). In the CO(2) group, the mean (SD) dose of midazolam was significantly lower than that of the control group; 5.6 +/- 4.9 mg and 9.7 +/- 5.9 mg, respectively (P = .005). Blood analysis revealed a slight pCO(2) elevation in the CO(2) group; however, only 2 patients complained of mild abdominal discomfort.

LIMITATIONS

Abdominal discomfort and pCO(2) were not evaluated in the control group.

CONCLUSIONS

This study strongly suggests that CO(2) insufflation is safe and effective during lengthy colonic endoscopic procedures, eg, ESD, with the patient under conscious sedation.

Impact of immunohistochemically identified lymphatic invasion on nodal metastasis in early gastric cancer

BACKGROUND

Among various clinical and pathological findings, lymphatic invasion (Ly) is the strongest risk factor for nodal metastasis in gastric cancer. However, the diagnosis of Ly is subjective and often inaccurate because of the difficulty of detecting lymphatic vessels with conventional hematoxylin and eosin (HE) staining.

METHODS

The distribution of lymphatics in the normal gastric wall was immunohistochemically characterized using a new selective marker of lymphatic endothelium, D2-40, in surgical specimens resected for early gastric cancer (EGC). Then, Ly in the primary lesion was reevaluated, and the positive (PPV) and negative (NPV) predictive values for nodal metastasis were comparatively examined for Ly detected by HE staining (Ly-HE) and by immunohistochemical staining (Ly-IM) in 131 cases of EGC.

RESULTS

D2-40-positive lymphatic vessels were observed in the deep proper mucosal layer, and the lymphatic vessel density (LVD) was extremely high in the muscularis mucosa (MM) layer. The number of Ly-IM-positive cases (15/131) was higher than the Ly-HE-positive cases (10/131). In 48 cases of intestinal-type cancer, Ly-IM had a PPV of 33.3% (2/6) and anNPV of 100% (42/42), which was more accurate than the corresponding figures for Ly-HE (25% and 98%, respectively). In contrast, the accuracy of Ly-IM was similar to that of Ly-HE in 83 cases of diffuse-type cancer.

CONCLUSION

Lymphatic vessels are most densely distributed in the MM layer in the gastric wall. Immunohistochemical identification of lymphatics is useful to increase the accuracy of diagnosing Ly in resected gastric EGCs. Ly-IM is superior to Ly-HE as a predictor of nodal metastasis, at least for intestinal-type EGC.

Endoscopic submucosal dissection for stomach neoplasms

Recent advances in techniques of therapeutic endoscopy for stomach neoplasms are rapidly achieved. One of the major topics in this field is endoscopic submucosal dissection (ESD). ESD is a new endoscopic technique using cutting devices to remove the tumor by the following three steps: injecting fluid into the submucosa to elevate the tumor from the muscle layer, pre-cutting the surrounding mucosa of the tumor, and dissecting the connective tissue of the submucosa beneath the tumor. So the tumors are resectable in an en bloc fashion, regardless of the size, shape, coexisting ulcer, and location. Indication for ESD is strictly confined by two aspects: the possibility of nodal metastases and technical difficulty, which depends on the operators. Although long-term outcome data are still lacking, short-term outcomes of ESD are extremely favourable and laparotomy with gastrectomy is replaced with ESD in some parts of therapeutic strategy for early gastric cancer.

The detection, surveillance and treatment of premalignant gastric lesions related to Helicobacter pylori infection

Gastric cancer is an important worldwide health problem and causes considerable morbidity and mortality. It represents the second leading cause of cancer-related death worldwide. A cascade of recognizable precursor lesions precedes most distal gastric carcinomas. In this multistep model of gastric carcinogenesis, Helicobacter pylori causes chronic active inflammation of the gastric mucosa, which slowly progresses through the premalignant stages of atrophic gastritis, intestinal metaplasia and dysplasia to gastric carcinoma. Detection and treatment of premalignant lesions may thus provide a basis for gastric cancer prevention. However, at present, premalignant changes of the gastric mucosa are frequently disregarded in clinical practice or result in widely varying follow-up frequency or treatment. This review provides an overview of current knowledge on detection, surveillance and treatment of patients with premalignant gastric lesions, and identifies the uncertainties that require further research.

Advantage of endoscopic submucosal dissection compared with EMR for early gastric cancer

BACKGROUND

In EMR of early gastric cancer (EGC), en bloc resection reduces the risk of residual cancer. Endoscopic submucosal dissection (ESD) now allows en bloc resection of large EGCs.

OBJECTIVE

To retrospectively determine whether ESD is more advantageous than EMR for EGCs.

DESIGN

EMR (825 lesions, 711 patients) or ESD (195 lesions, 185 patients) was performed. The en bloc resection rate, histologically complete resection rate, operation time, complications, and local recurrence rate were studied in relation to ulceration.

SETTING

Hiroshima University Hospital.

PATIENTS

Subjects comprised 896 patients in whom 1020 EGCs were resected endoscopically from 1990 to 2004.

RESULTS

In cases without ulceration, en bloc and histologically complete resection rates were significantly higher with ESD than with EMR, regardless of tumor size. The frequency of ulceration did not differ significantly between groups. Average operation time was significantly longer for ESD than for EMR, regardless of tumor size. Also, regardless of ulceration, the incidence of intraoperative bleeding was significantly higher with ESD (22.6%) than with EMR (7.6%). Delayed bleeding did not differ. In cases with ulceration, the incidence of perforation was significantly higher with ESD (53.8%) than with EMR (2.9%). Local recurrences were treated by incomplete EMR (en bloc, 2.9%; piecemeal, 4.4%). No patient experienced recurrence after ESD.

CONCLUSIONS

ESD increased en bloc and histologically complete resection rates and may reduce the local recurrence rate. Increased operation time and complication risks with ESD in comparison with EMR remain problematic. Special measures are necessary for ESD of ulcerated lesions to reduce the rates of perforation and incomplete resection.

Clinical efficacy of EMR with submucosal injection of a fibrinogen mixture: a prospective randomized trial

BACKGROUND

Submucosal injection is essential to performing EMR easily, and various solutions have been proposed to create a long-lasting submucosal fluid cushion.

OBJECTIVE

To assess the efficacy of a fibrinogen mixture (FM) as a submucosal injection solution.

DESIGN

A prospective, randomized, controlled trial.

SETTING

At a tertiary care, academic medical center.

PATIENTS

A total of 72 patients with early gastric neoplasm were randomly assigned to receive EMR with submucosal injection of normal saline solution (NS) or an FM.

INTERVENTION

We performed EMR only with a conventional method.

MAIN OUTCOME MEASUREMENTS

En bloc resection rate, complete resection rate, complications, and other procedure-related outcomes.

RESULTS

No significant differences were observed between the 2 groups (the FM group vs the NS group) in the rates of en bloc resection (80.6% vs 88.9%), complete resection rate (86.1% vs 80.6%), and recurrence rate (3% vs 6.1%). Mean procedure time was significantly shorter in the FM group vs the NS group (11.39 +/- 3.07 minutes vs 13.93 +/- 3.26 minutes; P < .05). Mean submucosal injection volume of the FM group was significantly less than that of the NS group (9.81 +/- 2.26 mL vs 14.32 +/- 2.35 mL; P < .05). Also, additional submucosal injection to maintain elevation of the lesion was less frequently required in the FM group than in the NS group (5.6% vs 33.3%; P < .05).

LIMITATIONS

The main limitations were the method of EMR (only included the conventional method) and the size of lesions (<30 mm), because a long-lasting submucosal fluid cushion was more important in the dissection method and larger tumors.

CONCLUSIONS

The FM is a reliable submucosal injection solution for conventional EMR.

Endoscopic submucosal dissection for stomach neoplasms

Recent advances in techniques of therapeutic endoscopy for stomach neoplasms are rapidly achieved. One of the major topics in this field is endoscopic submucosal dissection (ESD). ESD is a new endoscopic technique using cutting devices to remove the tumor by the following three steps: injecting fluid into the submucosa to elevate the tumor from the muscle layer, pre-cutting the surrounding mucosa of the tumor, and dissecting the connective tissue of the submucosa beneath the tumor. So the tumors are resectable in an en bloc fashion, regardless of the size, shape, coexisting ulcer, and location. Indication for ESD is strictly confined by two aspects: the possibility of nodal metastases and technical difficulty, which depends on the operators. Although long-term outcome data are still lacking, short-term outcomes of ESD are extremely favourable and laparotomy with gastrectomy is replaced with ESD in some parts of therapeutic strategy for early gastric cancer.

Endoscopic submucosal dissection for stomach neoplasms

Recent advances in techniques of therapeutic endoscopy for stomach neoplasms are rapidly achieved. One of the major topics in this field is endoscopic submucosal dissection (ESD). ESD is a new endoscopic technique using cutting devices to remove the tumor by the following three steps: injecting fluid into the submucosa to elevate the tumor from the muscle layer, pre-cutting the surrounding mucosa of the tumor, and dissecting the connective tissue of the submucosa beneath the tumor. So the tumors are resectable in an en bloc fashion, regardless of the size, shape, coexisting ulcer, and location. Indication for ESD is strictly confined by two aspects: the possibility of nodal metastases and technical difficulty, which depends on the operators. Although long-term outcome data are still lacking, short-term outcomes of ESD are extremely favourable and laparotomy with gastrectomy is replaced with ESD in some parts of therapeutic strategy for early gastric cancer.

Endoscopic submucosal dissection allows curative resection of locally recurrent early gastric cancer after prior endoscopic mucosal resection

BACKGROUND

Repeat endoscopic mucosal resection (EMR) to cure locally recurrent early gastric cancer (EGC) is difficult to perform because the initial EMR causes submucosal fibrosis; however, ESD allows submucosal dissection through the fibrosis and provides an en bloc specimen.

OBJECTIVE

The objective was to determine the safety and efficacy of ESD and compare the results to historical controls.

DESIGN

This was a retrospective, case-control study.

PATIENTS

We used our prospectively entered database (1993-2003) to identify 64 patients who had locally recurrent EGC after EMR.

MAIN OUTCOME MEASUREMENTS

We defined the resections as curative when the lateral and vertical margins were free of cancer and repeat endoscopy showed no recurrent disease.

RESULTS

Among 46 patients who underwent ESD, 41 (89.1%) en bloc resections were achieved compared to none in 18 conventional procedures (P < .0001). The specimen of 1 lesion (2.4%) out of 41 en bloc resections was histologically nonevaluable, compared with 10 lesions (43.4%) in 23 piecemeal resections (P < .0001). Three residual tumors (27.3%) were found in the 11 nonevaluable specimens. Three perforations occurred during ESD; all were successfully treated endoscopically with endoclips.

LIMITATIONS

The limitation of the study was retrospective design.

CONCLUSIONS

ESD provides high en bloc resection rate for locally recurrent EGC after previous EMR. In turn, en bloc resections allow precise histological staging to be assessed and prevent residual disease and recurrence.