Endoscopic mucosal resection

Combined endolaparoscopic intragastric excision for gastric neoplasms

BACKGROUND

The aim of this study was to describe our technique of combined endolaparoscopic approach to the management of intraluminal gastric neoplasms and to review the clinical outcome.

METHODS

Between February 2006 and January 2008, a total of 12 patients with gastric neoplasm < or =4 cm with a mainly intraluminal component received the combined endolaparoscopic intragastric excision and were prospectively analyzed. All lesions were localized endoscopically and then treated by using a combined endoscopic submucosal dissection and laparoscopic intragastric technique.

RESULTS

Eight of 12 lesions were gastrointestinal stromal tumours. The remaining lesions were adenomatous polyp with focal intramucosal adenocarcinoma, leiomyoma, and pancreatic heterotopia. All except 1 case was successfully treated with this technique (91.6%). There were no mortalities, and there was only 1 case of reactionary hemorrhage from the port site requiring a reoperation. The median operating time was 120 minutes, with a median blood loss of 35 mL. Length of hospital stay ranged from 3 to 12 days. There were no recurrences during the follow-up period.

CONCLUSIONS

This combined endolaparoscopic intragastric excision technique is a truly minimally invasive alternative for selected gastric neoplasm. It is safe and feasible with a satisfactory short-term outcome.

Endoscopic submucosal dissection with sheath-assisted counter traction for early gastric cancers

AIM

Endoscopic submucosal dissection (ESD) is associated with frequent complications, such as bleeding and perforation. The procedure is technically difficult, requires considerable skill and is longer than conventional endoscopic mucosal resection (EMR). Thus, non-invasive tools and methods are needed to facilitate direct visualization of the submucosal layer during ESD.

METHODS

An insulation-tipped (IT) knife was inserted into one channel, and a conventional injection sheath was inserted to the other channel of a double-channel fiberscope. The submucosal layer was lifted via a circumferential incision using the conventional injection sheath for visualizing cutting lines, and the submucosal layer under the lesion was directly dissected from the underlying muscularis propria.

RESULTS

Sheath-assisted traction resulted in successful ESD with en bloc resection in all 25 patients. Hemostasis and manipulation of blood vessels were uncomplicated and dissection was completed safely, without either bleeding or perforation. The movement of the sheath was not suppressed while lifting the submucosal layer and the IT knife could be moved freely, which allowed submucosal dissection independently of the sheath movement.

CONCLUSION

Sheath-assisted traction ESD, using simple materials and methods, has several advantages over other standard traction methods. Our procedure is straightforward, safe, non-invasive, cost-effective and uses readily available instruments to enhance visualization of cutting lines.

Clinical trial: rebamipide promotes gastric ulcer healing by proton pump inhibitor after endoscopic submucosal dissection--a randomized controlled study

BACKGROUND

Endoscopic submucosal dissection (ESD) is useful for treating gastric tumors. Several trials have shown the efficacy of 4 or 8 weeks of proton pump inhibitor (PPI) administration for post-ESD ulcers. However, if the size of the post-ESD ulcer is larger than predicted, PPI administration alone might not be sufficient for the ulcer to heal within 4 weeks. We examined the efficacy of a combination therapy of PPI and rebamipide, a mucosal-protective antiulcer drug, on the acceleration of post-ESD ulcer healing.

METHODS

Patients were randomly assigned to either the PPI and rebamipide therapy or the PPI alone. Sixty-two consecutive patients with gastric tumors gave informed consent for enrolling in the study. In all cases, the estimated size of the post-ESD ulcer was larger than 20 mm. Oral administration of the drug was started on the 2nd day post-ESD and continued to the 28th day.

RESULTS

All patients received the assigned pharmaceuticals and adhered well to the treatment regimen for 28 days. The endpoint ulcers reached S1 (scar stage) in 11/31 (36%) patients in the PPI-only group and in 21/31 (68%) in the combination group (P = 0.010).

CONCLUSIONS

The combination of PPI plus rebamipide was more effective than the PPI alone for treating ulcers larger than 20 mm within 4 weeks after ESD.

Large endoscopic mucosal resection for colorectal tumors exceeding 4 cm

AIM: To evaluate the feasibility and the outcome of endoscopic mucosal resection (EMR) for large colorectal tumors exceeding 4 cm (LCRT) undergoing piecemeal resection.

METHODS: From January 2005 to April 2008, 146 digestive tumors larger than 2 cm were removed with the EMR technique in our department. Of these, 34 tumors were larger than 4 cm and piecemeal resection was carried out on 26 colorectal tumors. The mean age of the patients was 71 years. The mean follow-up duration was 12 mo.

RESULTS: LCRTs were located in the rectum, left colon, transverse colon and right colon in 58%, 15%, 4% and 23% of cases, respectively. All were sessile tumors larger than 4 cm with a mean size of 4.9 cm (4-10 cm). According to the Paris classification, 34% of the tumors were type Is, 58% type IIa, 4% type IIb and 4% type IIc. Pathological examination showed tubulous adenoma in 31%, tubulo-villous adenoma in 27%, villous adenoma in 42%, high-grade dysplasia in 38%, in situ carcinoma in 19% of the cases and mucosal carcinoma (m2) in 8% of the cases. The two cases (7.7%) of procedural bleeding that occurred were managed endoscopically and one small perforation was treated with clips. During follow-up, recurrence of the tumor occurred in three patients (12%), three of whom received endoscopic treatment.

CONCLUSION: EMR for tumors larger than 4 cm is a safe and effective procedure that could compete with endoscopic submucosal dissection, despite providing incomplete histological assessment.

Risk factors for lymph node metastasis from gastric cancers with submucosal invasion

BACKGROUND

Accurate prediction of the metastatic status of lymph nodes (LNs) is clinically important for selecting treatment strategies in patients with gastric cancer with submucosal invasion (GCSM). In this study, we determined the risk factors for lymph node metastasis (LNM), including micrometastasis, in patients with GCSM.

MATERIALS AND METHODS

A total of 5610 LNs dissected from 189 patients with GCSM who had undergone a standard gastrectomy were immunostained with CAM 5.2 monoclonal antibody to detect LN micrometastasis. Clinicopathological risk factors for lymph node metastasis (LNM), including micrometastasis, were determined.

RESULTS

LNM was detected in 216 LNs (107 macroscopic metastases, 72 micrometastases, and 37 isolated tumor cells) in 55 (29.1%) of the 189 patients with GCSM. A multivariate analysis revealed that a tumor size of more than 20 mm, a mixed- or undifferentiated-type histology, a vertical tumor invasion depth in the submucosal layer (VTIDSM) of more than 0.5 mm, and the presence of lymphatic vessel invasion (LVI) were independent risk factors for LNM. The incidences of LNM in patients with 0, 1, 2, 3, and 4 risk factors were 0, 4.5, 11.4, 36.1, and 52.9%, respectively. Among the patients with only 1 or 2 risk factors, all the metastatic lesions were located only in the first tier. On the other hand, LNM in the second tier was also detected in 24.5% of the patients with more than 3 risk factors.

CONCLUSIONS

Tumor size, histologic type, VTIDSM, and LVI are important risk factors for predicting the presence and extent of LNM in patients with GCSM.

Efficacy of an endo-knife with a water-jet function (Flushknife) for endoscopic submucosal dissection of superficial colorectal neoplasms

OBJECTIVES

Endoscopic submucosal dissection (ESD) is currently not a common treatment for colorectal neoplasms because it is time consuming and technically difficult. Flushknife--an electrosurgical endo-knife with a water-jet function--is expected to reduce the difficulty of colorectal ESD. The objective of this study was to investigate the efficacy of a water-jet function for colorectal ESD.

METHODS

This study was a prospective randomized controlled trial, which was conducted at a cancer referral center. A total of 49 patients, with a total of 51 superficial colorectal neoplasms (median tumor size of 30 mm), were enrolled and randomly assigned to undergo ESD using either the Flexknife (electrosurgical endo-knife without a water-jet function) or the Flushknife. Tumors were resected by ESD using each endo-knife. The procedures were conducted by two endoscopists. Operation time was defined as the main outcome measure.

RESULTS

En bloc resection was achieved in 23 out of 26 (88%) lesions in the Flexknife group and in 24 out of 24 (100%) lesions in the Flushknife group. The mean operation time (95% confidence interval) was 87.3 (71.3-103.4) min in the Flexknife group and 61.0 (49.3-72.7) min in the Flushknife group (P=0.02). The Flushknife reduced the number of endoscopic device changes (P=0.001), the number of submucosal injections (P=0.001), and the mean amount of injected hyaluronate sodium (P=0.001) compared with the Flexknife. No severe adverse events were observed in either group.

CONCLUSIONS

Without increasing adverse events, the endo-knife with a water-jet function efficiently reduced the operation time of colorectal ESD in patients with large superficial colorectal neoplasms. (University hospital Medical Information Network Clinical Trials Registry number UMIN000001302).

A randomised study of hydro-jet vs. needle injection for lifting colorectal lesions prior to endoscopic resection

BACKGROUND

Submucosal lifting of lesions prior to endoscopic resection is crucial to reduce complications and improve the technical feasibility of the procedure.

AIM

To compare a self-assembled hydro-jet system vs. standard needle injection for tissue elevation prior to endoscopic resection of colorectal lesions.

METHODS

Randomised study performed at a single tertiary care institution. Consecutive patients with colonoscopic diagnosis of sessile polyps or non-polypoid lesions >5 mm or laterally spreading tumours.

OUTCOME MEASURES

successful elevation, time to proper elevation, completeness of excision, cautery damage, and general histological diagnostic quality (blinded pathologic assessment).

RESULTS

79 patients were randomised to hydro-jet (40 patients, group A) and needle (39 patients, group B) elevation. Successful elevation was achieved in 97.5% and 94.8%, respectively. Time to proper elevation was 8+/-5 s vs. 18+/-3 s (p<0.05). In group A, histology showed selective accumulation of fluid in the submucosa with intact collagen fibres. Damage to muscularis mucosa was never noted in the specimens of group A and in 7 cases of group B (p<0.01). Artefacts from "cautery effect" were very limited. Radial margins of resection could be adequately evaluated in all cases and were negative.

CONCLUSIONS

The hydro-jet system is as effective and safe as standard needle injection for tissue elevation prior to endoscopic resection of colorectal lesions, but it is significantly faster.

Pilot study to assess the safety of local lidocaine injections during endoscopic submucosal dissection for early gastric cancer

BACKGROUND

In Japan, endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) is performed by endoscopists on patients under sedation. There is an increased risk of anesthesia-related complications due to the higher sedative doses required during lengthier ESDs, so we sought to determine whether a local pain control method could safely reduce such doses.

METHODS

Twenty EGC patients enrolled in this study received local lidocaine injections during ESDs at our hospital (lidocaine group; LG). Electrocardiography, heart rate, oxygen saturation, and blood pressure were monitored during and after the ESDs, along with the doses of midazolam and pentazocine. Pain assessments were recorded for LG patients on the day of their ESDs and the following day.

RESULTS

The mean volume of lidocaine injection solution was 55.4 ml and the mean dose of lidocaine was 236 mg (range, 100-300 mg). The mean size of the resected specimens was 39.3 mm and mean procedure time was 66.0 min. There were no lidocaine-related complications, and electrocardiography, heart rate, oxygen saturation and blood pressure measurements were normal. In comparison to 157 consecutive patients (control group; CG), who had similar characteristics and had undergone ESDs previously with submucosal injections of conventional normal saline solution, the mean +/- SD pentazocine dose of 15.8 +/- 10.3 mg in the LG was significantly lower (P < 0.01) than the dose of 23.1 +/- 9.5 mg in the CG, and none of the LG patients complained of abdominal pain on the day of their ESDs, whereas such pain was reported by 17% (27/157) of the CG.

CONCLUSION

Local lidocaine injections into the submucosal layer were safe when administered during ESDs performed on EGC patients under sedation.

Incidence of lymph node metastasis and the feasibility of endoscopic resection for undifferentiated-type early gastric cancer

BACKGROUND

Endoscopic resection (ER) has been accepted as minimally invasive treatment in patients with early gastric cancer (EGC) who have a negligible risk of lymph node metastasis. It has already been determined which lesions in differentiated-type EGC present a negligible risk of lymph node metastasis, and ER is being performed for these lesions. In contrast, no consensus has been reached on which lesions in undifferentiated-type (UD-type) EGC present a negligible risk for lymph node metastasis, nor have indications for ER for UD-type EGC been established.

METHODS

We investigated 3843 patients who had undergone gastrectomy with lymph node dissection for solitary UD-type EGC at the Cancer Institute Hospital, Tokyo, and the National Cancer Center Hospital, Tokyo. Seven clinicopathological factors were assessed for their possible association with lymph node metastasis.

RESULTS

Of the 3843 patients, 2163 (56.3%) had intramucosal cancers and 1680 (43.7%) had submucosal invasive cancers. Only 105 (4.9%) intramucosal cancers compared with 399 (23.8%) submucosal invasive cancers were associated with lymph node metastases. By multivariate analysis, tumor size 21 mm or more, lymphatic-vascular capillary involvement, and submucosal penetration were independent risk factors for lymph node metastasis (P < 0.001, respectively). None of the 310 intramucosal cancers 20 mm or less in size without lymphatic- vascular capillary involvement and ulcerative findings was associated with lymph node metastases (95% confidence interval, 0-0.96%).

CONCLUSION

UD-type intramucosal EGC 20 mm or less in size without lymphatic-vascular capillary involvement and ulcerative findings presents a negligible risk of lymph node metastasis. We propose that in this circumstance ER could be considered.

Endoluminal therapy for esophageal disease: an introduction

This introductory article summarizes decades of research from many dedicated gastrointestinal endoscopists. It provides a background to Barrett esophagus (BE), exploring the risk of progression to dysplasia and esophageal adenocarcinoma. Two premalignant conditions, BE and colon adenoma, are compared, including their progression to esophageal adenocarcinoma and colon and rectal carcinoma, respectively. A comparison of the risks of surgical treatment and post-surgical complications of these cancers and of the strikingly different paradigms for their prevention is presented. The article concludes with the rationale for endoscopic treatment of Barrett disease.

Treatment of solitary extramedullary plasmacytoma of the stomach with endoscopic submucosal dissection

Extramedullary plasmacytoma (EMP) is an uncommon manifestation of plasma cell neplasia, which occurs outside the bone marrow. Intestinal involvement usually occur secondarily in multiple myeloma but it occur primarily less commonly. We experienced a woman who had a primary EMP localized in the stomach and the EMP was removed successfully by endoscopic submucosal dissection. The lesion was pathologically confirmed as confined to the gastric mucosa.

Surveillance and treatment for second primary cancer in the gastric tube after radical esophagectomy

BACKGROUND

Recent improvement in the survival of patients after esophagectomy for esophageal cancer has led to increasing occurrence of second primary cancer in the pulled-up stomach as gastric tube cancer (GTC). However, a treatment strategy for GTC including surveillance has not been established. The aims of this study are to clarify the incidence and clinicopathological characteristics of GTC and to assess the treatment results of endoscopic resection.

METHODS

Twenty-five patients with 29 GTC lesions treated between 1989 and 2007 were analyzed retrospectively.

RESULTS

The median interval between esophagectomy and GTC detection was 86 months, and the 10-year cumulative incidence rate of GTC was 8.6%. Of 18 asymptomatic GTCs, 17 lesions (94.4%) were detected by periodic endoscopy and 15 (88.2%) of them were treated endoscopically. Of all 29 GTCs, endoscopic submucosal dissection (ESD) was performed in 10 GTCs with a completely curative resection rate of 90%, which was significantly higher than that of 7 GTCs treated with endoscopic mucosal resection (EMR) (14.3%, P = 0.004). In these 17 GTCs, no cancer recurrence developed during a median follow-up period of 24 months, and the 3-year survival rate was 80.8%.

CONCLUSIONS

For patients after esophagectomy with gastric pull-up, long-term follow-up including periodic endoscopy is necessary to detect a potentially curable GTC. ESD is a feasible and safe procedure for GTC, with oncologically favorable features.

Self-assembled hydro-jet system for submucosal elevation before endoscopic resection of nonpolypoid colorectal lesions (with video)

BACKGROUND

Endoscopic resection of colorectal nonpolypoid lesions requires adequate submucosal lifting of the lesion.

OBJECTIVE

To evaluate a self-assembled hydro-jet system for tissue elevation to improve endoscopic resection of colorectal nonpolypoid lesions.

DESIGN

Prospective study.

SETTING

Single-center teaching hospital.

MAIN OUTCOME MEASUREMENTS

Efficacy and safety of the hydro-jet system and rate of complete resection.

RESULTS

The system was clinically applied in 31 patients to remove a total of 34 lesions throughout the colon. An adequate submucosal fluid cushion was achieved in all but 1 case without any lifting-associated complications. Complete endoscopic resection was possible in all 33 lifted lesions by using a snare. The size of the resected lesions ranged from 7 to 60 mm. Major intraprocedure bleeding occurred in only 1 case. No perforation or late bleeding was recorded. Histological examination showed a selective accumulation of fluid in the submucosa with edema and dissociation of submucosal structures, with no damage to the muscularis mucosa and very limited "burn effect" hampering assessment of radial margins.

LIMITATIONS

Lack of controls.

CONCLUSIONS

This inexpensive system allows safe and rapid submucosal lifting of colorectal nonpolypoid lesions to assist endoscopic resection.

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.

A comparison of transanal excision and endoscopic resection for early rectal cancer

AIM: To compare the outcomes of endoscopic resection with transanal excision in patients with early rectal cancer.

METHODS: Thirty-two patients with early rectal cancer were treated by transanal excision or endoscopic resection between May 1999 and December 2007. The patients were regularly re-examined by means of colonoscopy and abdominal computed tomography after resection of the early rectal cancer. Complications, length of hospital-stay, disease recurrence and follow up outcomes were assessed.

RESULTS: Sixteen patients were treated by endoscopic resection and 16 patients were treated by transanal excision. No significant differences were present in the baseline characteristics. The rate of complete resection in the endoscopic resection group was 93.8%, compared to 87.5% in the transanal excision group (P = 0.544). The mean length of hospital-stay in the endoscopic resection group was 2.7 ± 1.1 d, compared to 8.9 ± 2.7 d in the transanal excision group (P = 0.001). The median follow up was 15.0 mo (range 6-99). During the follow up period, there was no case of recurrent disease in either group.

CONCLUSION: Endoscopic resection was a safe and effective method for the treatment of early rectal cancers and its outcomes were comparable to those of transanal excision procedures.

Technical feasibility of endoscopic submucosal dissection for early gastric cancer in patients taking anti-coagulants or anti-platelet agents

BACKGROUND

Endoscopic submucosal dissection is a novel technique that is expected to be a curative treatment for early gastric cancers. Anti-coagulants and anti-platelet agents are widely used, especially in elderly patients, to prevent thromboembolic disease. However, the feasibility of endoscopic submucosal dissection for such patients has not been investigated.

AIMS

To determine the feasibility of endoscopic submucosal dissection for patients using anti-coagulant and anti-platelet agents via retrospective investigation of clinical outcomes.

METHODS

Of 408 patients with 444 early gastric cancers consecutively treated by endoscopic submucosal dissection from January 2000 to December 2007 in our hospital, 47 patients with 56 early gastric cancers were receiving anti-coagulants or anti-platelet agents. All patients were classified into groups for high and low risk of thromboembolism. In 44 low-risk patients, these agents were stopped for 1 week before and after treatment. Only three high-risk patients underwent intravenous heparin replacement during the cessation period.

RESULTS

Comparison with other patients showed no significant differences in complete en-bloc resection (96.4%) or perforation (1.8%). Postoperative bleeding requiring endoscopic treatment occurred for six early gastric cancers (10.7%) in the anti-coagulant and anti-platelet group; this frequency was slightly higher than that observed for other patients (5.2%). The healing of endoscopic submucosal dissection ulcers was not delayed by anti-coagulant and anti-platelet treatment (91% in the scarring stage) when checked at the 8th week after endoscopic submucosal dissection.

CONCLUSION

The clinical outcomes of endoscopic submucosal dissection for early gastric cancers in patients receiving anti-coagulants or anti-platelet agents indicated that endoscopic submucosal dissection for low-risk patients could be a reliable technique with equivalent efficacy and risk in comparison with that for other early gastric cancer patients.

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.

Application of endoscopic submucosal dissection for removal of deep invasive submucosal colon carcinoma

Endoscopic submucosal (sm) dissection (ESD) is a recently used technique that enables en-bloc resection of large colorectal tumors allowing a more precise histopathological analysis of the resected specimen. However, it has not been widely adopted even in Japan mainly due to its technical difficulty and increased risk of perforation. Herein, we present an ESD-treated lesion with deep sm invasion removed without complications, such as bleeding or perforation, from a patient at high-risk for surgical intervention. A successful ESD was achieved although the sm invasion was greater than 1000 mum from the muscularis mucosae, and the nonlifting sign was positive. It is our belief that this procedure should be performed at least in patients at high-risk for surgical intervention. At present, we have removed 16 lesions with deep sm invasion by ESD without complications, demonstrating that deep sm cancer can be successfully resected by this technique as a local resection. Herein, we report on one of these cases.

Treatment strategy for laterally spreading tumors in Japan: before and after the introduction of endoscopic submucosal dissection

BACKGROUND AND AIMS

Laterally spreading tumors (LST) in the colorectum are considered good candidates for endoscopic resection (ER). Because LST-non-granular (NG) tumors show multifocal invasion into the submucosal layer, en bloc resection is necessary for adequate histopathological evaluation. Therefore, surgical resection has been recommended when a lesion is suspected to be an invasive cancer and too large to resect en bloc. The aim of the present study was to evaluate whether the introduction of colorectal ESD, which was developed for en bloc resection of early gastric cancers, could improve the en bloc resection rate of large LST-NG-type tumors and reduce the surgical resection rate.

METHODS

Between January 1999 and December 2005, a total of 166 LST-NG-type tumors measuring > or = 20 mm in 161 patients were included in this study. The en bloc resection rate and the surgical resection rate were historically compared between two periods, before and after the introduction of ESD.

RESULTS

The en bloc resection rate for ER lesions was significantly higher in the latter period (35.0% [14/40]vs 76.5% [75/98]; P < 0.001), and the rate of surgery for adenomas and intramucosal or sm minute cancers was significantly lower in the latter period (20.0% [10/50]vs 1.1% [1/89]; P < 0.001).

CONCLUSIONS

The introduction of colonic ESD was able to change our treatment strategy for LST, improving the en bloc resection rate and reducing the surgical resection rate.

Endoscopic submucosal dissection (ESD) for colorectal tumors

BACKGROUND

Endoscopic submucosal dissection (ESD) is accepted as a minimally invasive treatment for early gastric cancer, however, it is not widely used in the colorectum because of its technical difficulty.

OBJECTIVE

To determine the feasibility of using ESD for treating large superficial colorectal tumors.

PATIENTS

A total of 400 consecutive patients were treated by ESD for 405 lesions at National Cancer Center Hospital, Tokyo, Japan.

INTERVENTIONS

Endoscopic submucosal dissection procedures were performed using a bipolar needle knife (B-knife) or an insulation-tip knife (IT knife).

RESULTS

The en-bloc resection rate was 87% and the curative resection rate was 86% among the 405 ESDs: 101 involved tubular adenomas, 255 intramucosal cancers and minute submucosal cancers, 46 submucosal deep cancers and 3 others (MALT and carcinoid tumors). The median operation time was 90 minutes and the mean size of resected specimens was 40 mm (range: 15 mm-150 mm). Perforations occurred in 14 (3.5%) cases and postoperative bleeding in four (1%) cases, but only one perforation case needed emergency surgery because endoscopic clipping was ineffective.

LIMITATIONS

Conducted at single center.

CONCLUSIONS

Endoscopic submucosal dissection is a feasible technique for treating large superficial colorectal tumors because it provides a higher en-bloc resection rate and is less invasive than surgical resection.

Endoclipping for gastric perforation secondary to second session of EMRC in locally residual early gastric cancer: a case report

A 72-year-old woman underwent gastric endoscopic mucosal resection with a cap-fitted endoscope for an adenocarcinoma in situ. She was scheduled for endoscopic follow-up at 1 and 3 months after the procedure. By the third month of follow up, biopsies of a slightly depressed scar area showed an high grade epithelial dysplasia. For this reason a second endoscopic resection (ER) was performed using the oblique soft cap. A perforation in the site of endoscopic resection was immediately observed. The complication was treated successfully by the application of seven clips.

Evaluation of a manually driven, multitasking platform for complex endoluminal and natural orifice transluminal endoscopic surgery applications (with video)

BACKGROUND

The Direct Drive Endoscopic System (DDES) is a multitasking platform developed to overcome the limitations of the currently available rigid and flexible endoscopic systems in application to natural orifice transluminal endoscopic surgery (NOTES), single-port laparoscopy, and advanced endoluminal procedures. The system consists of a 3-channel, steerable guide sheath accepting a 6-mm endoscope and two 4-mm articulating instruments. The system's overall design enables the interventionalist to operate instruments bimanually from a stable platform, conveying a laparoscopic paradigm to the functional working space at the distal end of the flexible guide sheath.

OBJECTIVE

To assess the basic functionality of the DDES device in a series of defined exercises by using ex vivo porcine stomachs and 1 in vivo animal model.

DESIGN

Ex vivo calibration and training exercises, including EMR, full-thickness suturing, and knot tying.

SETTING

Animal laboratory.

INTERVENTIONS

EMR, full-thickness suturing, and knot tying.

MAIN OUTCOME MEASUREMENTS

Successful completion of specified tasks.

RESULTS

Independent instrument movement with a wide range of motion allowed the interventionalist to perform several complex tasks efficiently. The DDES was able to (1) grasp tissue and hold it under tension, (2) cut through layers of porcine stomach in a controlled fashion, (3) suture, and (4) tie knots.

LIMITATION

Ex vivo study.

CONCLUSIONS

This novel multitasking platform demonstrated surgical functionality including triangulation, cutting, grasping, suturing, and knot tying. Preliminary results suggest that the DDES can perform complex endosurgical tasks that have traditionally been challenging or impossible with the standard endoscopic paradigm, and may enable NOTES, single-port laparoscopy, and complex endoluminal procedures.

Clinical outcome of endoscopic submucosal dissection versus endoscopic mucosal resection of large colorectal tumors as determined by curative resection

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) has recently been applied to the treatment of superficial colorectal cancer. Clinical outcomes compared with conventional endoscopic mucosal resection (EMR) have not been determined so our aim was to compare the effectiveness of ESD with conventional EMR for colorectal tumors >or=20 mm.

METHODS

This was a retrospective case-controlled study performed at the National Cancer Center Hospital in Tokyo, Japan involving 373 colorectal tumors >or=20 mm determined histologically to be curative resections. Data acquisition was from a prospectively completed database. We evaluated histology, tumor size, procedure time, en bloc resection rate, recurrence rate, and associated complications for both the ESD and EMR groups.

RESULTS

A total of 145 colorectal tumors were treated by ESD and another 228 were treated by EMR. ESD was associated with a longer procedure time (108 +/- 71 min/29 +/- 25 min; p < 0.0001), higher en bloc resection rate (84%/33%; p < 0.0001) and larger resected specimens (37 +/- 14 mm/28 +/- 8 mm; p = 0.0006), but involved a similar percentage of cancers (69%/66%; p = NS). There were three (2%) recurrences in the ESD group and 33 (14%) in the EMR group requiring additional EMR (p < 0.0001). The perforation rate was 6.2% (9) in the ESD group and 1.3% (3) in the EMR group (p = NS) with delayed bleeding occurring in 1.4% (2) and 3.1% (7) of the procedures (p = NS), respectively, as all complications were effectively treated endoscopically.

CONCLUSIONS

Despite its longer procedure time and higher perforation rate, ESD resulted in higher en bloc resection and curative rates compared with EMR and all ESD perforations were successfully managed by conservative endoscopic treatment.

Endoscopic submucosal dissection of large colorectal tumors by using a novel spring-action S-O clip for traction (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) allows en bloc resection of large GI neoplasms, regardless of their size; however, technical difficulties associated with ESD in the colorectum make it less widely applied in the treatment of tumors in this region. To address this difficulty, we designed a rubber strip-based traction device, called the S-O clip (Sakamoto-Osada clip) and reported previously that ESD with this device was effective for complete resection of large, superficial colorectal neoplasms. In this report, we describe a novel spring-action version of the S-O clip (spring S-O clip) that improves the facility of clip use during ESD of colorectal tumors.

OBJECTIVE

To evaluate the efficacy and safety of the spring S-O clip for ESD of colorectal neoplasms.

DESIGN

Case series.

SETTING

Juntendo University Hospital.

MAIN OUTCOME MEASUREMENTS

The efficacy and safety of the spring S-O clip traction device during ESD of colorectal tumors.

RESULTS

In 3 cases, a large, superficial neoplasm in the right side of the colon was removed safely and successfully en bloc without complication. Procedure times for the 3 cases were 44, 27, and 49 minutes, with resected specimens measuring 40, 24, and 35 mm, respectively.

LIMITATION

Uncontrolled study.

CONCLUSION

This limited case series demonstrates that spring S-O clip-assisted ESD is safe and effective for en bloc resection of large superficial neoplasms in the right side of the colon.

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.

Chromoendoscopy

Chromoendoscopy involves the use of stains or dyes during endoscopy to improve the visualization and characterization of the gastrointestinal mucosa. Its main clinical application is the detection of dysplasia or early cancer of the gastrointestinal tract in individuals with pre-malignant conditions or hereditary and environmental factors that predispose them to cancer. The utility of chromoendoscopy has been mostly studied in squamous cell carcinoma of the esophagus, Barrett's esophagus, gastric cancer, colorectal polyps, and chronic ulcerative colitis. Although chromoendoscopy has been shown to be feasible and safe, several limitations have prevented its widespread use in endoscopy. Despite this, chromoendoscopy remains a useful adjunct to standard white light endoscopy in the visualization of mucosal lesions, which may potentially improve tissue diagnosis and impact patient care.

Endoscopic submucosal dissection for colorectal epithelial neoplasm

BACKGROUND

Endoscopic submucosal dissection (ESD), a new widely accepted method for treating early gastric cancer, was developed to increase the en bloc rate, especially for lesions larger than 20 mm in diameter. This study aimed to evaluate the efficacy and safety of ESD for colorectal epithelial neoplasms.

METHODS

From July 2006 to December 2007, ESD was indicated for patients with colorectal epithelial neoplasms larger than 20 mm in diameter. The rates of curative en bloc resection, the procedure time, and the incidence of complications were investigated.

RESULTS

A total of 74 colorectal epithelial neoplasms were resected by ESD. The mean diameter of these lesions was 32.6 mm (range, 20-85 mm). The rate of en bloc resection was 93.2% (69/74), and the mean ESD procedure time was 110 min (range, 80-185 min). None of patients had massive hemorrhage during ESD, and only one patient (1.4%) bled 8 days after ESD. Six patients experienced perforation, and all except one recovered after several days of conservative treatment. The patient who did not recover underwent urgent surgery. The perforation rate was 8.1% (6/74). All the patients were followed up. Healing of the artificial ulcer was confirmed, and with no lesion residue or recurrence was found.

CONCLUSIONS

The findings show ESD to be effective for colorectal epithelial neoplasm, making it possible to resect the whole lesion in one piece and to provide precise histologic information.

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.

[Endoscopic mucosal resection of Abrikosoff's tumor of the esophagus]

Abrikosoff's tumor (AT), or granular cell tumor (GCT), is relatively rare in the gastrointestinal tract, where the most common site is the esophagus. This tumor is usually found incidentally when an upper gastrointestinal endoscopy is carried out for another reason. Endoscopically, GCT appears as a small, yellow and submucosal lesion covered by normal mucosa. Endoscopic ultrasonography shows a homogeneous hypoechoic lesion with well defined margins. The definitive diagnosis is histological. The origin of GCT is neurogenic and the tumor is composed of eosinophilic granular cytoplasm and PAS-positive cells, which show the S-100 protein on immunohistochemistry. Although GCT is usually clinically and histologically benign, some malignant cases have been reported. Consensus is lacking on the treatment and follow-up of this tumor. Currently, endoscopic mucosal resection is a safe and effective technique to treat submucosal esophageal lesions, allowing subsequent histologic analysis. We present three patients with esophageal CGT, who were definitively treated with endoscopic mucosal resection.

Submucosal injection solution for gastrointestinal tract endoscopic mucosal resection and endoscopic submucosal dissection

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) have provided new alternatives for minimally invasive treatment of gastrointestinal adenomas and early-stage cancers that involve a minimum risk of lymph-node metastasis. The use of submucosal injections is essential to the success of these endoscopic resection techniques. The “ideal” submucosal injection solution should provide a sufficiently high submucosal fluid cushion for safe and effective EMRs and ESDs while also preserving lesion tissue for accurate histopathological assessment. In the past, normal saline (NS) solution was commonly used for this purpose, but it is difficult to achieve the proper submucosal elevation and maintain the desired height with NS. Therefore, other safe and effective facilitative submucosal injection solutions have been developed that also take into account relevant cost-benefit considerations. This review examines recent advances in the development of effective submucosal injection solutions for use during endoscopic resections.

Polyps in the gastrointestinal tract: discrepancy between endoscopic forceps biopsies and resected specimens

BACKGROUND AND AIM

An endoscopic forceps biopsy (EFB) carries the risk of missing the neoplastic foci within a polyp as only a small portion of the lesion is sampled using this technique. Accordingly, the histological examination of specimens obtained by an EFB is of limited accuracy and patient management based on the histological findings is controversial. The aim of this prospective study was to determine the diagnostic concordance between an EFB and resected tissues of gastric and colon polyps.

METHODS

Between January 2006 and October 2007, 1312 gastrointestinal polyps from 896 patients were resected in our hospital. Patients with polyps of epithelial origin of at least 8 mm in diameter and not associated with polyposis syndromes were included in the study. Polyps of nonepithelial origin were excluded. One thousand two hundred and sixty-four polyps of epithelial origin [gastric polyps (n=268) and colon polyps (n=996)] obtained from 813 patients met the inclusion criteria. All patients underwent an EFB and resection of the polyp by endoscopic mucosal resection and endoscopic submucosal dissection.

RESULTS

Multiple polyps existed in 31.6% of the patients. The pathological diagnoses of resected gastric polyps were as follows: adenomas with low-grade dysplasia, 46 (17.2%); adenomas with high-grade dysplasia, 42 (15.7%); hyperplastic polyps, 126 (47.0%); chronic inflammatory polyps, 29 (10.8%); and adenocarcinomas, 25 (9.3%). The discrepancy rate between an EFB and the pathology of the resected gastric polyps was 39.2% (the Kendall's tau-b and the kappa coefficient for agreement between the EFB and resected specimens of gastric polyps were 0.577 and 0.472, respectively; P value <0.001). No relationship between the size of the gastric polyp and the concordance rate was observed. The pathological diagnoses of the resected colon polyps were as follows: adenomas with low-grade dysplasia, 559 (56.1%); adenomas with high-grade dysplasia, 229 (23.0%); hyperplastic polyps, 44 (4.4%); adenocarcinomas, 53 (5.3%); and inflammatory polyps, 111 (11.1%). The discrepancy rate between the EFB and the pathology of the resected colon polyps was 39.8%. (the Kendall's tau-b and the kappa coefficient for agreement between the EFB and the resected specimens of the colon polyps were 0.479 and 0.293, respectively; P value <0.001). No relationship between the size of the colon polyp and the concordance rate was observed.

CONCLUSION

Considerable discrepancies were observed in histological findings between the EFB and the resected specimens. Therefore, complete removal of the entire polyp is recommended to confirm the diagnosis, to remove precancerous lesions, and to develop an optimal management plan.

Local recurrence after endoscopic resection of colorectal tumors

BACKGROUND AND AIMS

Local recurrence frequently occurs after endoscopic resection of large colorectal tumors. However, appropriate intervals for surveillance colonoscopy to assess local recurrence after endoscopic resection have not been clarified. The aim of the present study was to determine local recurrence rates following en-bloc and piecemeal endoscopic resection and establish appropriate surveillance colonoscopy intervals based on retrospective analysis of local recurrences.

MATERIALS AND METHODS

A total of 461 patients with 572 > or = 10-mm lesions underwent endoscopic resection and follow-up. We retrospectively compared local recurrence rates on lesion size, macroscopic type, and histological type after en-bloc resection (440 lesions) and piecemeal resection (132 lesions). Cumulative local recurrence rates were analyzed using the Kaplan-Meier method.

RESULTS

Local recurrence occurred for 34 lesions (5.9%). Local recurrence rates for the en-bloc and piecemeal groups was 0.7% (3/440) and 23.5% (31/132), respectively (P < 0.001). The difference between the two groups was distinct in terms of lesion size, macroscopic type, and histological type. Of the 34 local recurrences, 32 were treated endoscopically and two cases required additional surgery. The 6-, 12-, and 24-month cumulative local recurrence rate of the en-bloc group was 0.24%, 0.49%, and 0.81%. Then the 6-, 12-, and 24-month cumulative local recurrence rate for the piecemeal group was 18.4%, 23.1%, and 30.7%.

CONCLUSION

Local recurrence occurred more frequently after piecemeal resection than en-bloc resection. However, almost all cases of local recurrences could be cured by additional endoscopic resection, so piecemeal resection can be acceptable treatment.

Meshed capillary vessels by use of narrow-band imaging for differential diagnosis of small colorectal polyps

BACKGROUND

Although microvascular vessels on the surface of colorectal polyps are observed by narrow-band imaging (NBI) with magnification, its clinical usefulness is still uncertain.

OBJECTIVE

Our purpose was to evaluate the usefulness of meshed capillary (MC) vessels observed by NBI magnification for differentiating between nonneoplastic and neoplastic colorectal lesions.

DESIGN

Prospective polyp study.

SETTING

National Cancer Center Hospital East, Chiba, Japan.

PATIENTS

A total of 702 consecutive patients who underwent total colonoscopy between September and December 2004 were prospectively evaluated. Patients with polyps >10 mm and those with polyps previously evaluated by histologic examination or colonoscopy were excluded.

INTERVENTION

Lesions were classified into 2 groups: polyps with invisible or faintly visible MC vessels as nonneoplastic and polyps with clearly visible MC vessels as neoplastic. Lesions judged as nonneoplastic were subjected to biopsy and those as neoplastic were removed endoscopically. Histologic analysis was performed in all lesions.

MAIN OUTCOME MEASUREMENT

Visible or invisible surface MC vessels, prediction of histologic diagnosis.

RESULTS

Of 92 eligible patients enrolled in this study, 150 lesions, including 39 (26%) hyperplastic polyps and 111 (74%) adenomatous polyps, were detected. Observation of MC vessels detected 107 of 111 neoplastic polyps and 36 of 39 nonneoplastic polyps. The overall diagnostic accuracy, sensitivity, and specificity were 95.3%, 96.4%, and 92.3%, respectively.

LIMITATIONS

MC vessel judgment performed by a single colonoscopist with extensive experience in magnifying NBI.

CONCLUSION

Observation of surface MC vessels by magnifying NBI is a useful and simple method for differentiating colorectal nonneoplastic and neoplastic polyps.

Usefulness and safety of 0.4% sodium hyaluronate solution as a submucosal fluid "cushion" for endoscopic resection of colorectal mucosal neoplasms: a prospective multi-center open-label trial

BACKGROUND

Sodium hyaluronate (SH) solution has been used for submucosal injection in endoscopic resection to create a long-lasting submucosal fluid "cushion". Recently, we proved the usefulness and safety of 0.4% SH solution in endoscopic resection for gastric mucosal tumors. To evaluate the usefulness of 0.4% SH as a submucosal injection solution for colorectal endoscopic resection, we conducted an open-label clinical trial on six referral hospitals in Japan.

METHODS

A prospective multi-center open-label study was designed. A total of 41 patients with 5-20 mm neoplastic lesions localized in the colorectal mucosa at six referral hospitals in Japan in a single year period from December 2002 to November 2003 were enrolled and underwent endoscopic resection with SH. The usefulness of 0.4% SH was assessed by the en bloc complete resection and the formation and maintenance of mucosal lesion-lifting during endoscopic resection. Safety was evaluated by analyzing adverse events during the study period.

RESULTS

The usefulness rate was high (82.5%; 33/40). The following secondary outcome measures were noted: 1) steepness of mucosal lesion-lifting, 75.0% (30/40); 2) intraoperative complications, 10.0% (4/40); 3) time required for mucosal resection, 6.7 min; 4) volume of submucosal injection, 6.8 mL and 5) ease of mucosal resection, 87.5% (35/40). Two adverse events of bleeding potentially related to 0.4% SH were reported.

CONCLUSION

Using 0.4% SH solution enabled sufficient lifting of a colorectal intramucosal lesion during endoscopic resection, reducing the need for additional injections and the risk of perforation. Therefore, 0.4% SH may contribute to the reduction of complications and serve as a promising submucosal injection solution due to its potentially superior safety in comparison to normal saline solution.

A new technique for gastric endoscopic submucosal dissection: peroral traction-assisted endoscopic submucosal dissection

BACKGROUND

Compared with conventional EMR, endoscopic submucosal dissection (ESD) has a higher en bloc resection rate and complete resection rate, regardless of tumor size, in treating gastric neoplasms. However, ESD leads to more complications, such as bleeding or perforation, and, in particular, needs more procedure time than a conventional EMR.

OBJECTIVE

To report a new technique for ESD, peroral traction-assisted ESD with suture material, to perform easier and more rapid procedures in treating gastric neoplasms and to report the technique's early results.

DESIGN

A case series.

SETTING

A tertiary medical center.

PATIENTS AND METHODS

A total of 15 patients with gastric adenomas or early gastric cancers larger than 10 mm in diameter were consecutively enrolled. After marking around the periphery of the lesion, submucosal injection, followed by circumferential mucosal incision with a Flex-knife and an insulation-tipped knife, was conducted. After that, one hemostatic clip, tied by using a white silk suture, was applied at a site of the lesion suitable for oral traction. During submucosal dissection, the applied suture material was pulled to the oral side. Additional tractions were applied as needed.

MAIN OUTCOME MEASUREMENTS

En bloc resection rate, procedure time, complications.

RESULTS

All lesions were resected en bloc with free lateral and vertical margins by using this technique. The mean longest lesion size and specimen size were 18.1 mm (range 11-28 mm) and 43.7 mm in diameter (range 25-64 mm), respectively. The mean procedure time was 49.6 minutes (range 28-90 minutes). There was no significant bleeding that required blood transfusion or perforation related to the procedures.

LIMITATIONS

Single endoscopist, small patient number.

CONCLUSION

Peroral traction-assisted ESD with suture material is useful in treating gastric neoplasms located in various regions of the stomach. It may make ESD procedures easier, faster, and safer under better direct vision of the submucosal layer.

Prospective clinical trial of magnetic-anchor-guided endoscopic submucosal dissection for large early gastric cancer (with videos)

BACKGROUND

The treatment of early gastric cancer (EGC) by endoscopic submucosal dissection (ESD) has been rapidly gaining popularity in Japan. However, the procedure needs a high quality of skill. To facilitate complicated ESD by using a single working-channel gastroscope ("one-hand surgery method"), the magnetic-anchor-guided ESD (MAG-ESD) controlled by an extracorporeal electromagnet was reported to be successful in a porcine model.

OBJECTIVES

The purpose of this prospective clinical trial was to evaluate the feasibility of MAG-ESD for large EGC located on the gastric body in human beings.

DESIGN

Prospective clinical trial at a single center.

SETTING

National Cancer Center Hospital, Tokyo, Japan.

SUBJECTS

From January 2005 to May 2006, 25 patients with EGC >20 mm in diameter, located in the gastric body, and intestinal-type histology were enrolled. Patients with a cardiac pacemaker, advanced malignancy in other organs, severe cardiac and/or pulmonary diseases, and uncontrolled hypertension and/or diabetes mellitus were excluded from this study.

INTERVENTIONS

Similar to a standard ESD, the MAG-ESD procedure was performed with the patient under conscious sedation by intravenous injection of midazolam (3-5 mg) and pentazocine (15 mg).

MAIN OUTCOME MEASUREMENTS

Unfavorable events and other intraoperative complications caused by the magnetic anchor or the magnetic force were recorded and evaluated. Two GI endoscopists (T.G., I.O.) assessed whether the magnetic anchor facilitated gastric ESD according to 2 criteria: "supportive" and "not supportive." The en bloc resection rate, complications, total operation time, bleeding, perforation, and recurrence rate were also evaluated. The total operation time was measured from insertion to withdrawal of the endoscope, including the retrieving of the magnetic anchor or anchors.

RESULTS

All tumors were resected en bloc, without any perforations or severe uncontrollable bleeding. All magnetic anchors were safely retrieved. Two endoscopists assessed that the MAG system was supportive in 23 patients. None of the patients experienced physiologic and mental abnormalities as a result of long-term magnetic-field exposure. During a median follow-up of 20 months (15-32 months), neither delayed adverse effects nor allergies caused by the stainless steel of the magnetic anchor were observed.

CONCLUSIONS

MAG-ESD is a feasible and safe method that allowed an excellent visualization by suitable tissue tension and facilitated gastric ESD in patients with EGC. The system should be miniaturized to make it applicable in daily clinical practice.

Stretching Causes Extensive Changes of Gastric Submucosa: Is It Acceptable to Define 500 microm as the Safe Margin?

BACKGROUND/AIMS

Endoscopic mucosal resection can cure early gastric cancer. The risk of lymphatic metastasis is related to the depth of submucosal invasion by the mucosal malignancy, with a resection depth of 500 microm generally accepted as a safe cut-off. However, excessive thinning induced by stretching of the resected tissue sometimes preventing a precise diagnosis. We studied the effects of stretching on different layers and sites of gastric tissue.

METHODS

Porcine stomachs were cut into 2.0x2.0 cm pieces, and pieces from body were stretched to 2.5, 3.0, and 3.5 cm. Pieces from the cardia, body, and antrum were also stretched to 3.0 cm. The thickness of each layer was measured and analyzed statistically.

RESULTS

Whole gastric wall and submucosal layers showed gradual thinning, with stretching to 3.5 cm tearing the tissues and resulting in imperfect extension. The submucosa was thinner in body tissue than in cardia and antrum tissues. Stretching to 3.0 cm induced a consistent decrease in submucosal thickness (30-70%). The change in thickness varied widely between individual samples.

CONCLUSIONS

A resection margin of 500 microm might be insufficient for the complete removal of malignancy. Moreover, the thickness of the submucosal layer differs with the gastric site and between individuals. Future studies are needed to confirm the findings in human tissue.

Treatment strategy after non-curative endoscopic resection of early gastric cancer

BACKGROUND

Endoscopic resection (ER) is indicated for patients with early gastric cancer who have a negligible risk of lymph node metastasis (LNM). Histological examination of the resected specimen may indicate a possible risk of LNM or a positive resection margin. These patients are considered to have undergone non-curative ER. The aim of this study was to determine the appropriate treatment strategy for such patients.

METHODS

A total of 298 patients who had non-curative ER were classified into those with a positive lateral margin only (group 1; 72 patients) and those with a possible risk of LNM (group 2; 226 patients).

RESULTS

Surgery was performed within 6 months of non-curative ER in 19 patients in group 1 and 144 in group 2. In group 1, nine patients were found to have local residual tumours, all limited to the mucosal layer without LNM. In Group 2, 13 patients had residual disease, including four local tumours without LNM, two local tumours with LNM and seven cases of LNM alone. The rate of LNM after surgery was 6.3 per cent in group 2.

CONCLUSION

Surgery remains the standard treatment after non-curative ER in patients with a possible risk of LNM.

Endoscopic resection of superficial gastrointestinal tumors

Therapeutic endoscopy plays a major role in the management of gastrointestinal (GI) neoplasia. Its indications can be generalized into four broad categories; to remove or obliterate neoplastic lesion, to palliate malignant obstruction, or to treat bleeding. Only endoscopic resection allows complete histological staging of the cancer, which is critical as it allows stratification and refinement for further treatment. Although other endoscopic techniques, such as ablation therapy, may also cure early GI cancer, they can not provide a definitive pathological specimen. Early stage lesions reveal low frequency of lymph node metastasis which allows for less invasive treatments and thereby improving the quality of life when compared to surgery. Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are now accepted worldwide as treatment modalities for early cancers of the GI tract.

Different solutions used for submucosal injection influenced early healing of gastric endoscopic mucosal resection in a preclinical study in experimental pigs

Background

We hypothesised that different solutions for submucosal injection may influence early healing of endoscopic mucosal resection (EMR). The aim of this study was to evaluate histological and immunological changes after EMR in experimental pigs.

Materials and methods

Two parallel EMRs on the anterior and posterior wall of the gastric body were performed by means of the cap technique in 21 female pigs. A glycerol-based solution (anterior EMR) and hydroxypropyl methylcellulose solution (posterior EMR) were applied for submucosal injection. The animals were sacrificed 7 days later, and tissue sections of all EMRs were stained using combined trichrome. Computer image analysis was used for objective evaluation of elastic and collagen fibres content. Two-colour indirect immunophenotyping of blood and gastric samples were performed using mouse anti-pig monoclonal antibodies.

Results

The values of collagen fibre content 7 days after EMR were significantly higher in lesions after the use of solution A in comparison with solution B (2.10 ± 0.25% versus 1.57 ± 0.25%, p = 0.009). Concordant results were found in elastic fibres (3.23 ± 0.49% versus 2.93 ± 0.61%, p = 0.018). No systemic changes in major leukocyte subpopulations were found. In gastric tissue, lymphocyte subsets exhibited only minor changes. CD4⁺ T-lymphocytes were increased in the healing tissue after EMR using solution A (17.08 ± 9.24% versus 9.76 ± 7.97%, p = 0.011). Significant increase of SWC3⁺ leukocytes was observed after EMR using solution B (47.70 ± 25.41% versus 18.70 ± 12.16%, p = 0.001).

Conclusions

The use of glycerol-based solution for submucosal injection was associated with more pronounced histological signs of early healing of EMRs compared with hydroxypropyl methylcellulose.

Helicobacter pylori eradication therapy may facilitate gastric ulcer healing after endoscopic mucosal resection: a prospective randomized study

BACKGROUND AND AIM

It remains unclear whether Helicobacter pylori eradication therapy affects the healing rate of iatrogenic ulcers following endoscopic mucosal resection (EMR) for gastric tumors. The aim of our study was to prospectively evaluate the effect of H. pylori eradication therapy on gastric ulcer healing after EMR.

METHODS

After EMR, patients were randomly assigned to either the H. pylori eradication group (Hp group) (lansoprazole 30 mg, amoxicillin 1000 mg, and clarithromycin 500 mg, twice a day for 7 days) or the noneradication group (proton pump inhibitor, PPI group) (lansoprazole 30 mg, twice a day for 7 days). Four weeks after EMR, the ulcer stages and size were compared between the two groups. Moreover, ulcer-related symptoms, bleeding rates, adverse effects, and drug compliance were compared.

RESULTS

A total of 64 patients were enrolled. Of these, 17 patients were excluded from the study. The two groups were comparable in terms of baseline clinicopathologic characteristics. Four weeks after EMR, the two groups did not differ with respect to ulcer stage (p = .475) or ulcer-related symptoms (p = .399). However, the ulcer reduction ratio was significantly higher in the Hp group (0.028 +/- 0.024 vs. 0.065 +/- 0.055, p < .05). No differences were observed between the two groups with regard to drug compliance, adverse drug event rates, or bleeding rates.

CONCLUSIONS

Our results suggest that H. pylori eradication therapy might improve the ulcer healing rate after EMR.

Role of endoscopic ultrasound in superficial esophageal cancer

The recent increase in the incidence of superficial esophageal cancer and promising developments in potentially curative endoscopic therapies have placed endoscopic ultrasound in a central position with regard to decision making. This is a review of the literature to determine the role of endoscopic ultrasound and high frequency probe ultrasonography in the assessment of superficial esophageal carcinomas.

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.