Argon plasma coagulation for early gastric cancer: technique and outcome

Clinical outcomes of ablation of gastric dysplasia with argon plasma coagulation

BACKGROUND

Although several small cohort studies have shown the utility of argon plasma coagulation (APC) in the treatment of gastric dysplasia, its clinical significance has not been established. This study aims to assess the efficacy of APC as a first line treatment for gastric dysplasia, and identify risk factors for residual dysplasia.

METHODS

A total of 179 cases of gastric dysplasia were treated with APC and have been followed-up with upper endoscopy within 1 year. The overall incidence and the characteristics of lesions with residual dysplasia in follow-up endoscopy were analyzed by logistic regression.

RESULTS

Among 179 lesions treated with APC, 171 (95.5%) lesions have achieved complete ablation in the follow-up endoscopy. Additional APC was applied for residual dysplasia, achieving complete ablation in 97.77% (175/179). The upper third location of the gastric dysplasia was significantly associated with residual dysplasia, while tumor size, horizontal location, macroscopic morphology and grade of dysplasia showed no significant associations with residual dysplasia following the initial APC.

CONCLUSIONS

APC with meticulous follow-up can be recommended as a first line treatment in patients with gastric dysplasia.

Recent advances in endoscopic management of gastric neoplasms

The development and clinical application of new diagnostic endoscopic technologies such as endoscopic ultrasonography with biopsy, magnification endoscopy, and narrow-band imaging, more recently supplemented by artificial intelligence, have enabled wider recognition and detection of various gastric neoplasms including early gastric cancer (EGC) and subepithelial tumors, such as gastrointestinal stromal tumors and neuroendocrine tumors. Over the last decade, the evolution of novel advanced therapeutic endoscopic techniques, such as endoscopic mucosal resection, endoscopic submucosal dissection, endoscopic full-thickness resection, and submucosal tunneling endoscopic resection, along with the advent of a broad array of endoscopic accessories, has provided a promising and yet less invasive strategy for treating gastric neoplasms with the advantage of a reduced need for gastric surgery. Thus, the management algorithms of various gastric tumors in a defined subset of the patient population at low risk of lymph node metastasis and amenable to endoscopic resection, may require revision considering upcoming data given the high success rate of en bloc resection by experienced endoscopists. Moreover, endoscopic surveillance protocols for precancerous gastric lesions will continue to be refined by systematic reviews and meta-analyses of further research. However, the lack of familiarity with subtle endoscopic changes associated with EGC, as well as longer procedural time, evolving resection techniques and tools, a steep learning curve of such high-risk procedures, and lack of coding are issues that do not appeal to many gastroenterologists in the field. This review summarizes recent advances in the endoscopic management of gastric neoplasms, with special emphasis on diagnostic and therapeutic methods and their future prospects.

Endoscopic Submucosal Dissection for Esophageal Cancer: Current and Future

Endoscopic submucosal dissection (ESD) has been widely used to treat superficial esophageal cancer. The advantages of esophageal ESD include a high en bloc resection rate and accurate pathological diagnosis. It enables local resection of the primary tumor and accurate identification of the risk factors for lymph node metastasis, including depth, vascular invasion, and types of invasion. Even in cases with clinical T1b-SM cancer, ESD and additional treatment can achieve radical cure, depending on the risk of lymph node metastasis. Esophageal ESD will be increasingly vital in minimally invasive and effective esophageal cancer treatment. This article describes the current status and prospects of esophageal ESD.

ArgoCap - feasibility and safety of a novel over-the-scope device to facilitate endoscopic APC treatment

INTRODUCTION

Argon plasma coagulation (APC) is an electrosurgical procedure used, among other indications, for treatment of dysplastic Barrett's mucosa. Homogeneous and safe application can be compromised by varying distances and suboptimal angle of the probe to the tissue. In this study, we present ArgoCap, a novel endoscopic device developed to facilitate endoluminal APC treatment. Objectives of this preclinical study were to assess feasibility and safety and to determine suitable APC settings.

MATERIAL AND METHODS

One-hundred and thirty-two APC treatments of predefined areas using various APC settings were performed ex vivo in the opened porcine esophagus. Depth of thermal injury was assessed histologically. Feasibility of APC treatment in different locations was examined in 20 explanted porcine esophagi and in first in vivo porcine applications.

RESULTS

APC treatment in all quadrants of the esophagus was feasible. Histologically, thermal effects involving the whole thickness of the mucosa were visible with all settings. APC with pulsed mode resulted in deep thermal damage with all power settings. No lesions of the muscular layer occurred using precise (E8, E9) and forced (10 W, 20 W) mode.

CONCLUSIONS

Esophageal APC using ArgoCap is feasible and safe. The device has the potential to improve APC treatment of larger mucosal areas.

Long-term Outcomes of Additional Endoscopic Treatments for Patients with Positive Lateral Margins after Endoscopic Submucosal Dissection for Early Gastric Cancer

Background/Aims

It is uncertain whether additional endoscopic treatment may be chosen over surgery in patients with positive lateral margins (pLMs) as the only non-curative factor after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). We aimed to compare the long-term outcomes of additional endoscopic treatments in such patients with those of surgery and elucidate the clinicopathological factors that could influence the treatment selection.

Methods

A total of 99 patients with 101 EGC lesions undergoing additional treatment after non-curative ESD with pLMs as the only non-curative factor were analyzed. Among them, 25 (27 lesions) underwent ESD, 29 (29 lesions) underwent argon plasma coagulation (APC), and 45 (45 lesions) underwent surgery. Clinicopathological characteristics and long-term outcomes were compared.

Results

Residual tumor was found in 73.6% of cases. The presence of multiple pLMs was associated with higher risk of residual tumor (p=0.046). During a median follow-up of 58.9 months, recurrent or residual lesions after additional ESD and APC were found in 4% (1/25) and 6.8% (2/29) of patients, respectively. However, all were completely cured with surgery or repeated ESD. There were no extragastric recurrences after additional endoscopic treatment. Lymph node metastasis was identified after additional surgery in one (2.2%) patient with an EGC showing histological heterogeneity.

Conclusions

Given the favorable long-term outcomes, additional ESD or APC may be an acceptable choice for patients with pLMs as the only non-curative factor after ESD for EGC. However, clincopathological characteristics such as multiple pLMs and histological heterogeneity should be considered in the treatment selection.

Liquid nitrogen spray cryotherapy for intramucosal carcinoma and extensive gastric intestinal metaplasia with dysplasia

Background and Aims

Gastric intestinal metaplasia with dysplasia (GIM-D) that is visible as a discrete limited lesion on endoscopy is readily treated using endoscopic mucosal resection or endoscopic submucosal dissection. However, there are few options for more extensive and invisible dysplasia. Ablating a wide swath of tissue with argon plasma coagulation or radiofrequency ablation can be challenging and carries risks, including postprocedure ulceration. Liquid nitrogen spray cryotherapy is an established treatment for dysplasia in Barrett's esophagus, but its use for GIM-D has not been previously reported.

Methods

Three patients with intramucosal adenocarcinoma and GIM-D underwent a total of 10 sessions of spray cryotherapy. In all cases, spray cryotherapy was performed after passing an orogastric decompression tube into the stomach for active suctioning. Ablations were performed in cycles of 20 to 40 seconds, with at least 45 seconds between cycles to allow for tissue thawing. Between 2 and 7 ablations were performed during each procedure. Before each procedure, Sydney protocol biopsy specimens were obtained. No patient reported any postprocedure adverse events.

Results

The first patient underwent 3 sessions of spray cryotherapy; there was no evidence of GIM-D after 1 session, no evidence of gastric intestinal metaplasia after 3 sessions, and no recurrence after 29 months. The second patient underwent 5 sessions of spray cryotherapy; after 1 session there was no adenocarcinoma, and at 14 months there was only GIM-D. The third patient underwent 2 spray cryotherapy sessions, and after 1 session there was gastric intestinal metaplasia but no GIM-D.

Conclusions

Very few treatment modalities exist for extensive GIM-D. We present 3 cases in which off-label spray cryotherapy was used to treat extensive high-grade dysplasia with good treatment effect and patient tolerance. This adds to the body of literature supporting spray cryotherapy as a safe, well-tolerated, and effective treatment for extensive GIM-D.

Argon plasma coagulation for superficial squamous cell carcinoma in the residual esophagus after esophagectomy

BACKGROUND

Patients after esophagectomy for esophageal squamous cell carcinoma (SCC) occasionally develop metachronous SCC in the residual esophagus. Although most of these second primary lesions are detected as superficial cancer at follow-up endoscopy, it is often difficult to perform endoscopic resection for these lesions near the site of anastomosis.

METHODS

The objective of this study was to evaluate the effectiveness of argon plasma coagulation (APC) for superficial SCC in the residual esophagus after esophagectomy. Twelve patients (involving 15 s primary lesions) received APC for superficial SCC in the residual esophagus after esophagectomy. These lesions were difficult to perform endoscopic resection and they were treated using APC.

RESULTS

There was no treatment-related complication. Complete remission (CR) was achieved in 13 (86.6%) of the 15 lesions: CR was achieved in 11 lesions (73.3%) after the first APC course, and in another 2 lesions (13.3%) after two or more APC courses. Of the 2 patients with persisting residual tumor, 1 patient received 12 times repeated-APC courses over 6 years, and eventually achieved local control without metastasis, the other patient received radiotherapy and cervical esophagectomy after treatment failure with APC. All patients survived except for one patient who died of old age and another patient who died of tongue cancer.

CONCLUSIONS

APC was a safe treatment that was easy to perform. APC was concluded to be an effective treatment for superficial SCC in the residual esophagus after esophagectomy when endoscopic resection was difficult.

Usefulness of argon plasma coagulation for superficial esophageal squamous cell neoplasia in patients at high risk or with limited endoscopic resectability

BACKGROUND/AIMS

Endoscopic resection is the standard treatment for superficial esophageal squamous-cell neoplasia (SESCN). However, we encounter patients in whom endoscopic resection is difficult to perform. We retrospectively studied the usefulness of argon plasma coagulation (APC) in patients with SESCN.

MATERIALS AND METHODS

The study comprised 45 patients with SESCN (81 lesions) who underwent APC in our hospital from March 1999 through August 2016. Clinicopathological characteristics, treatment time, the presence or absence of metastasis and recurrence, adverse events, and outcomes were studied.

RESULTS

The median follow-up was 40 months. The median age was 70 years. The tumor diameter was 10 mm or longer in 48 lesions and less than 10 mm in 33 lesions. The median treatment time was 22 minutes. The reasons for selecting APC were as follows: technical difficulty caused by the presence of metachronous multiple lesions in the radiation field after chemoradiotherapy or close proximity to the ulcer scar remaining after endoscopic treatment in 49 lesions (60.4%), and the presence of underlying diseases in 26 lesions (32.0%). Adverse events occurred in 2 patients (4.4%) who had hypoxemia due to over-sedation. Two lesions (2.5%) recurred locally but could be locally controlled by additional APC. No patient had metastasis or recurrence or died of esophageal neoplasia. The 3-year overall survival rate was 87.0%, and the 3-year recurrence-free survival rate was 97.2%.

CONCLUSION

APC can be a useful treatment option for SESCN in patients with a limited life expectancy, poor performance status, or technical difficulty in resection of superficial neoplasms.

Comparison Between Redo Endoscopic Treatment and Surgery in Patients with Locally Recurrent Gastric Neoplasms

BACKGROUND

Treatment of locally recurrent gastric neoplasms after endoscopic resection remains challenging. We investigated the efficacy and safety of treatment options for recurrent gastric neoplasms localized to the scar of previous endoscopic submucosal dissection (ESD).

METHODS

The clinicopathological characteristics and treatment outcomes of patients who underwent endoscopic treatment or surgery for recurrent gastric neoplasms between June 2010 and May 2017 were retrospectively reviewed.

RESULTS

Of the 92 patients included, 74 underwent endoscopic treatment (51 redo ESD, 23 argon plasma coagulation [APC] ablation) and 18 underwent surgery. The redo ESD procedure time was significantly longer than that of the primary ESD (31.0 versus 22.0 min, p = 0.018). Overall, adverse events occurred in 11 patients (12.0%), with the incidence being significantly higher in the surgery group (27.8% versus 8.1% in the endoscopic treatment group, p = 0.036). Local recurrence-free survival rates were 81.1% for the endoscopic treatment group (86.3% and 69.6% for redo ESD and APC groups, respectively) and 100% for the surgery group (log rank p = 0.033). Logistic regression analysis showed that tumor size > 12.5 mm (odds ratio [OR] 5.14, 95% confidence interval [CI] 1.25-26.9, p = 0.032) and tumors located in the upper two-thirds of the stomach (OR 4.43, 95% CI 1.27-16.8, p = 0.023) were associated with non-curative resection after redo ESD.

CONCLUSIONS

Endoscopic treatment could be an effective and safe alternative to surgery for selected patients with gastric neoplasms recurring at the scar of previous ESD. Especially, patients having small lesions located in the distal part of the stomach could be a good candidate for redo ESD.

The optimal timing of additional surgery after non-curative endoscopic resection to treat early gastric cancer: long-term follow-up study

Patients with early gastric cancer (EGC) who undergo non-curative endoscopic resection (ER) require additional surgery. The aim of the study was to validate surgical and oncological outcomes according to the timing of additional surgery after non-curative endoscopic resection. We retrospectively analyzed long-term follow-up data on the 302 patients enrolled between January 2007 and December 2014. We validated our earlier suggestion that the optimal time interval from non-curative ER to additional surgery was 29 days. All patients were divided into two groups by reference to time intervals from ER to additional surgery of ≤29days (n = 133; group A) and >29 days (n = 169; group B). The median follow-up duration was 41.98 ± 21.23 months. As in our previous study, group B exhibited better surgical outcomes. A total of 10 patients developed locoregional or distant recurrences during the follow-up period, but no significant difference was evident between the two groups. Interestingly, the survival rate was better in group B. Group B (>29 days) exhibited better surgical and oncological outcomes. Thus, additional gastrectomy after non-curative ER should be delayed for 1 month to ensure optimal surgical and oncological outcomes.

Clinical outcomes of endoscopic treatment for gastric epithelial neoplasm in remnant stomach after distal gastrectomy

BACKGROUNDS/AIM

We aimed to evaluate the feasibility of endoscopic treatment for gastric epithelial neoplasm in the remnant stomach after distal gastrectomy and compared the clinical outcomes by tumor location and endoscopic treatment modality.

METHODS

We reviewed the data of patients who underwent endoscopic treatment for gastric epithelial neoplasms in the remnant stomach after distal gastrectomy between January 1996 and August 2013. The treatments included endoscopic resection or argon plasma coagulation.

RESULTS

Herein, 107 patients (median age, 65.1 years; 92 men) encompassing 117 cases of gastric neoplasms in the remnant stomach after distal gastrectomy were endoscopically treated. Forty of these lesions were located at anastomotic sites; they were treated with endoscopic resection in 29 cases (72.5%) and argon plasma coagulation in 11 cases (27.5%). For 77 lesions located on the non-anastomotic site, endoscopic resection was performed in 68 cases (88.4%) and argon plasma coagulation was performed in nine cases (11.7%; p = 0.031). The mean endoscopic resection duration was significantly longer in the anastomotic site group than in the non-anastomotic site group (43.6 vs. 26.3 min, p = 0.018). Recurrence was observed in five (12.8%) patients in the former and in one (1.3%) in the latter (p = 0.015); all the patients were successfully retreated with endoscopic resection or APC.

CONCLUSIONS

Endoscopic treatment for gastric epithelial neoplasm in a remnant stomach after distal gastrectomy is effective and safe. However, closely monitoring for recurrence should be conducted, particularly when the tumor is located at the anastomotic site.

Management of Early Stage Gastric and Gastroesophageal Junction Malignancies

Esophageal and gastric carcinomas are prevalent malignancies worldwide. In contrast to the poor prognosis associated with advanced stages of disease, early stage disease has a favorable prognosis. Early stage gastric cancer (ESGC) is defined as cancer in which the depth of invasion is limited to the submucosal layer of the stomach on histologic examination, regardless of lymph node status. ESGC that meets standard or expanded criteria can be treated via endoscopic mucosal resection and endoscopic submucosal dissection. Similar indications for endoscopic interventions exist for gastroesophageal junction and esophageal malignancies."

Long-term outcomes after noncurative endoscopic resection of early gastric cancer: the optimal time for additional endoscopic treatment

BACKGROUND AND AIMS

We aimed to evaluate long-term outcomes with noncurative endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) and surveillance strategies such as the optimal time for additional endoscopic treatment in patients with noncurative ESD.

METHODS

Of 2527 patients who underwent gastric ESD for EGC, 512 (20.3%) patients with noncurative resection were reviewed. Noncurative resection is defined as positive resected margins on histology, lymphovascular infiltration, or beyond the expanded criteria for ESD.

RESULTS

The mean ± standard deviation follow-up duration was 79.0 ± 55.7 months. A total of 264 patients (51.6%) and 50 patients (9.8%) underwent surgery and endoscopic treatment after noncurative resection, respectively, whereas 198 patients (38.7%) were observed. Cancer-specific survival and disease-free survival rates were significantly different among the surgery, other endoscopic treatment, and observation groups (96.7%, 86.8%, and 86.2%, respectively; P =.030; and 92.5%, 73.6%, and 63.0%, respectively; P < .001). When patients who underwent surgery were excluded, the disease-free survival rate of recurrence was not significantly different between the endoscopic treatment and observation groups (73.6% vs 63.0%; P = .548). To exclude the potential for the presence of lymph node metastasis, we further analyzed disease-free survival of local recurrence by comparing the patients with only a positive lateral resection margin. The disease-free survival rate was higher in the endoscopic treatment group than in the observation group (89.2% vs 69.1%; P = .023). Moreover, additional endoscopic treatment within 3 months showed significant associations with lower risk of local recurrence on multivariate analysis (hazard ratio, 0.017; 95% confidence interval, 0.002-0.260; P = .003).

CONCLUSIONS

In patients with noncurative ESD, additional surgery showed a better long-term outcome; moreover, when a positive lateral resection margin was the only noncurative factor, additional endoscopic treatment within 3 months could be considered to improve disease-free survival.

Cost-effectiveness and short-term clinical outcomes of argon plasma coagulation compared with endoscopic submucosal dissection in the treatment of gastric low-grade dysplasia

Endoscopic treatment such as endoscopic submucosal dissection (ESD) or argon plasma coagulation (APC) is widely performed to treat gastric low-grade dysplasia (LGD). We aimed to evaluate the clinical efficacy of APC versus ESD for gastric LGD in terms of cost-effectiveness. This was a retrospective review of patients with gastric LGD who were treated with endoscopic intervention (APC or ESD) between March 2011 to December 2015. Fifty-nine patients treated with APC and 124 patients treated with ESD were included. Patients in the APC group were significantly older (mean age, 67.68 vs 63.90 years, respectively, P < .01), had an increased rate of Helicobacter pylori infection (27.1 vs 10.5%, respectively, P < .01), and had a higher mean Charlson Comorbidity Index score (2.32 vs 0.38, respectively, P < .01) than those in the ESD group. The 2 groups did not differ in tumor size, location, macroscopic morphology, or surface configuration. The procedure time (11.31 vs56.44 minutes, respectively, P < .01), and hospital stay (3.2 vs 5.6 days, respectively, P < .01) were significantly, shorter in the APC group than in the ESD group. Additionally, the cost incurred was significantly, lower in the APC group than in the ESD group (962.03 vs 2,534.80 dollars, respectively, P < .01). APC has many advantages related to safety, and cost-effectiveness compared with ESD. Therefore, APC can be considered an alternative treatment option for gastric LGD.

The Usefulness of Argon Plasma Coagulation Compared with Endoscopic Submucosal Dissection to Treat Gastric Adenoma

Background/Aims

To date, the best therapeutic modality for gastric adenoma, especially low-grade adenoma, has not been established. The aim of this study was to assess the usefulness of argon plasma coagulation (APC) in treating gastric adenoma compared with endoscopic submucosal dissection (ESD).

Methods

We included 210 patients with gastric adenoma, who underwent treatment with either APC (97 patients) or ESD (113 patients). The clinical and pathologic characteristics, mean duration of hospital stay, complications, and recurrence rates between the two groups were compared.

Results

The mean adenoma size was 0.9 cm and 1.1 cm in the APC group and ESD group, respectively (p<0.001). The mean duration of hospital stay was significantly shorter in the APC group than in the ESD group (1.6 days vs. 5.8 days, p<0.001). Complications did not occur in the APC group. However, one case of perforation (0.9%) and 6 cases of bleeding (5.3%) occurred in the ESD group. The recurrence rates were 15.3% (15/97 patients) in the APC group and 3.5% (4/113 patients) in the ESD group (p=0.003). The proportion of hospitalization was less in the APC group (43.3%, 42/97) than in the ESD group (100.0%, 113/113) (p<0.001). Medical expense was less in the APC group (377,172 won) than in the ESD group (1,430,610 won) (p<0.001).

Conclusions

The findings of this study suggest that APC is a safe treatment method for gastric adenoma without serious complications. However, regular endoscopic follow-up is necessary to detect any residual or recurrent lesions due to the relatively high rate of local recurrence after APC.

Additive endoscopic resection may be sufficient for patients with a positive lateral margin after endoscopic resection of early gastric cancer

BACKGROUND AND AIMS

No well-established treatment strategies exist for lateral margin positivity (LM+) alone after endoscopic resection (ER) of early gastric cancer (EGC). Thus, we aimed to clarify a treatment strategy for non-curative resection (non-CR) with LM+ alone after ER in EGC.

METHODS

Among 2065 patients with EGC treated by ER, 76 (3.6%) with only LM+ after non-CR of EGC were reviewed retrospectively. Of these, 28 underwent gastrectomy, 25 underwent argon plasma coagulation (APC), and 23 underwent repeat ER (re-ER). We analyzed the clinicopathologic characteristics of all patients and compared those who underwent additive surgery, APC, or re-ER.

RESULTS

Of the 76 patients, 28 (36.8%) fulfilled the absolute criteria and 48 (63.2%) the expanded criteria for ER. Among the latter patients, the proportion undergoing additive surgery was 75.0%, higher than that of patients in the former group (P = .014). Residual cancer cells were observed in 70.6% of patients after additive surgery or re-ER. Residual cancer cells were observed significantly more often in patients with undifferentiated-type than in those with differentiated-type EGC (P = .02). However, no lymph node metastasis was observed in any patient after additive surgery.

CONCLUSIONS

Our results suggest that endoscopic treatment may be a sufficient additive therapy for patients with LM+ alone after ER, irrespective of whether the absolute or expanded ER criteria are used. However, as complete ablation of remnant cells cannot be guaranteed, re-ER is a better additive treatment than APC.

Therapeutic outcomes of endoscopic submucosal dissection of differentiated early gastric cancer in a Western endoscopy setting (with video)

BACKGROUND

Large multicenter gastric cancer endoscopic submucosal dissection (ESD) studies conducted at major Japanese institutions have reported en bloc resection, en bloc tumor-free margin resection, and curative resection rates of 92.7% to 96.1%, 82.6% to 94.5%, and 73.6% to 85.4%, respectively, with delayed bleeding and perforation rates of 0.6% to 6.0% and 3.6% to 4.7%, respectively. Although ESD is currently an alternative treatment in some countries, particularly in Asia, it remains uncertain whether ESD therapeutic outcomes in Western endoscopy settings can be comparable to those achieved in Japan.

OBJECTIVE

To evaluate the ESD therapeutic outcomes for differentiated early gastric cancer (EGC) in a Western endoscopy setting.

DESIGN/SETTING

Consecutive case series performed by an expertly trained Western endoscopist.

PATIENTS

Fifty-three patients with 54 lesions.

INTERVENTIONS

ESD for early gastric cancers (T1) satisfying expanded inclusion criteria.

MAIN OUTCOME MEASUREMENTS

En bloc resection, en bloc tumor-free margin resection, and curative resection rates were 98%, 93%, and 83%, respectively. The delayed bleeding rate was 7%, and the perforation rate was 4%.

RESULTS

The mean patient age was 67 years, and the mean tumor size was 19.8 mm, with 54% of the lesions located in the lesser curvature. The median procedure time was 61 minutes, with ESD procedures 60 minutes or longer associated with submucosal fibrosis (P < .001) and tumor size 25 mm or larger (P = .03). In every ESD procedure, both circumferential incision and submucosal dissection were performed by using a single knife. Two of the 4 delayed bleeding cases required surgery, and all perforations were successfully managed by using endoscopic clips.

LIMITATION

Long-term outcome data are currently unavailable.

CONCLUSION

ESD for differentiated EGC resulted in favorable therapeutic outcomes in a Western endoscopy setting comparable to those achieved at major Japanese institutions.

Clinical outcomes of argon plasma coagulation therapy for early gastric neoplasms

Background/Aims

Argon plasma coagulation (APC) has some merits in the treatment of gastric neoplasms including a shorter operative time and fewer complications compared with endoscopic mucosal resection or endoscopic submucosal dissection. However, there are few reports on the outcomes of gastric neoplasms treated using APC. The aim of this study was to evaluate APC in the treatment of early gastric neoplasms in terms of clinical efficacy, safety, and local recurrence.

Methods

We enrolled 28 patients who received APC therapy at the Kyungpook National University Hospital between May 2007 and April 2013. Clinical outcomes were analyzed.

Results

The median follow-up period was 24.8 months (range, 2 to 78). Among the 28 lesions treated using the APC procedure, tumor recurrence was encountered in seven lesions (25.0%). Recurrence was found in 50% (5/10) of single APC cases and 11% (2/18) of rescue APC cases. The mean time to recurrence was 16.1 months (range, 2 to 78). There were no serious APC-related complications such as perforation, bleeding, or infection.

Conclusions

APC therapy can be a useful treatment with a favorable safety profile for patients with early gastric neoplasms. However, further studies are necessary to determine the long-term prognosis of patients undergoing this treatment.

Gastric ESD: current status and future directions of devices and training

Endoscopic mucosal resection (EMR) of early gastric cancer, which has been proved to be safe and effective and is the established standard of care in Japan, has become increasingly established worldwide in the past decade. Endoscopic submucosal dissection (ESD) is superior to EMR, as it is designed to provide precise pathologic staging and long-term curative therapy based on an en bloc R0 specimen irrespective of the size and/or location of the tumor. However, ESD requires highly skilled and experienced endoscopists. The introduction of ESD to the Western world necessitates collaborations between Eastern and Western endoscopists, pathologists, and surgeons.

Is there an optimal surgery time after endoscopic resection in early gastric cancer?

BACKGROUND

The patients with early gastric cancer who have undergone incomplete endoscopic resection (ER) generally need additional surgery because of the possibility of lymph node metastasis. The aim of study was to evaluate the optimal time interval from ER to additive surgery by evaluating the effect of time interval on the surgical and oncological outcomes.

METHODS

We analyzed 154 patients who underwent additive gastrectomy after incomplete ER at Severance and Gangnam Severance Hospitals. The time interval point, at which operative time and estimated intraoperative blood loss (EBL) of the earlier operation group and the later operation group showed the greatest disparities, was evaluated. The patients were divided into 2 groups according to the time interval point, as the earlier operation group (group A) and the later operation group (group B). We retrospectively evaluated the clinicopathological characteristics and surgical and oncological outcomes.

RESULTS

The greatest difference between operative time and EBL was in the groups who underwent operation before and after 29 days. Of the 154 patients, 78 were in group A (≤29 days) and 76 in group B (>29 days). There were no differences in the clinicopathological characteristics and oncological outcomes except for tumor size. The operative time and EBL were significantly longer and more in group A compared with group B.

CONCLUSIONS

The time interval between ER and additive surgery is associated with surgical outcomes. Additive surgery at about 1 month after ER may be optimal for better surgical outcomes without affecting the oncological outcomes.

Endoscopic resection (endoscopic mucosal resection/ endoscopic submucosal dissection) for early gastric cancer

Endoscopic resection of early gastric cancer is a well-established standard therapy in Japan and Korea, and is increasingly used in other countries. Endoscopic resection should be curative for patients, and safe, easy and effective not only for patients, but also for endoscopists. Endoscopic submucosal dissection (ESD) is superior to standard endoscopic mucosal resection (EMR) as it is designed to provide en bloc R0 resection regardless of size and/or location. Correct pathological assessment of en bloc resected specimens is crucial for accurate diagnosis and patient stratification for the risk of metastasis. Outcome studies in Japan and Korea, countries with the highest incidence of gastric cancer, have shown that ESD is efficacious in leading to a good long-term outcome; however, ESD requires an experienced endoscopist with a high skill level. Expanded indications for endoscopic resection have been proposed, especially after large en bloc resection have been accomplished using ESD. The use of ESD could be of huge benefit for the management of gastrointestinal superficial neoplasms. However, for ESD to become a viable therapeutic option, it requires close and supportive working relationships between endoscopists, pathologists and surgeons.

Clinical outcomes of argon plasma coagulation for the treatment of gastric neoplasm

BACKGROUND

There are insufficient reports on the outcomes and local recurrence rates for gastric neoplasms treated using argon plasma coagulation (APC). The purpose of this study was to analyze the clinical outcomes in early gastric cancer or gastric adenoma patients following APC treatment.

METHODS

Seventy-one patients were enrolled and all underwent APC at the Asan Medical Center between July 2007 and August 2011. Clinical and oncological outcomes were analyzed.

RESULTS

The median follow-up period was 20 months (interquartile range 13-29 months). Among the 71 patients we evaluated, nonlifting after submucosal saline injection was found in 35 patients and 15 patients (21.2%) experienced local recurrence with a median period of 10 months (IQR 5-13 months). The rate of local recurrence was higher in the nonlifting group and the 40-W group than in the lifting group and the 60- or 80-W groups (31.4 vs. 11.1%, p = 0.045 and 31.7 vs. 6.7%, p = 0.017, respectively). Multivariate analysis showed that the power setting with the 40-W and nonlifting groups after submucosal injection was associated with local recurrence.

CONCLUSIONS

APC therapy after submucosal saline injection using high power (60 or 80 W) appears to be an effective alternative in the management of gastric neoplasm.

Argon plasma coagulation is safe and effective for treating smaller gastric lesions with low-grade dysplasia: a comparison with endoscopic submucosal dissection

BACKGROUND AND AIMS

The best therapeutic modality has not been established for gastric low-grade adenomas or dysplasia (LGD), which can progress to invasive carcinoma despite a low risk. This study aims to investigate the clinical efficacy, safety, and local recurrence after argon plasma coagulation (APC) treatment of gastric LGD compared with endoscopic submucosal dissection (ESD).

PATIENTS AND METHODS

A total of 320 patients with gastric LGD ≤ 2.0 cm treated with APC or ESD between 2004 and 2011 were retrospectively analyzed. We compared local recurrence rate, complication rate, procedure time, and admission to hospital between APC and ESD groups.

RESULTS

Of the 320 patients, 116 patients were treated with APC and 204 with ESD. During follow-up, local recurrence was more common in the APC group (3.8 %, 4/106) than the ESD group (0.5 %, 1/188; log-rank test P = 0.036). However, all patients with local recurrence (n = 5) were treated by additional APC, and followed up without further recurrences. ESD was complicated by two perforations (1.0 %, 2/204) compared with no perforations in the APC group (0 %, 0/116). Bleeding complications were not different between the APC (1.7 %, 2/116) and ESD (2.0 %, 4/204) groups. Procedure time was shorter in the APC (7.8 ± 5.1 min) than the ESD (53.1 ± 38.1 min) group (P < 0.001). The proportion of hospitalization was less in the APC group (31.0 %, 36/116) than the ESD group (100.0 %, 204/204) (P < 0.001).

CONCLUSIONS

APC can be a good treatment option for patients with LGD ≤ 2.0 cm.

Argon plasma coagulation for superficial esophageal squamous-cell carcinoma in high-risk patients

AIM: To evaluate the usefulness and safety of argon plasma coagulation (APC) for superficial esophageal squamous-cell carcinoma (SESC) in high-risk patients.

METHODS: We studied 17 patients (15 men and 2 women, 21 lesions) with SESC in whom endoscopic mucosal resection (EMR), endoscopic submucosal dissection (ESD), and open surgery were contraindicated from March 1999 through February 2009. None of the patients could tolerate prolonged EMR/ESD or open surgery because of severe concomitant disease (e.g., liver cirrhosis, cerebral infarction, or ischemic heart disease) or scar formation after EMR/ESD and chemoradiotherapy. After conventional endoscopy, an iodine stain was sprayed on the esophageal mucosa to determine the lesion margins. The lesion was then ablated by APC. We retrospectively studied the treatment time, number of APC sessions per site, complications, presence or absence of recurrence, and time to recurrence.

RESULTS: The median duration of follow-up was 36 mo (range: 6-120 mo). All of the tumors were macroscopically classified as superficial and slightly depressed type (0-IIc). The preoperative depth of invasion was clinical T1a (mucosal cancer) for 19 lesions and clinical T1b (submucosal cancer) for 2. The median treatment time was 15 min (range: 10-36 min). The median number of treatment sessions per site was 2 (range: 1-4). The median hospital stay was 14 d (range: 5-68 d). Among the 17 patients (21 lesions), 2 (9.5%) had recurrence and underwent additional APC with no subsequent evidence of recurrence. There were no treatment-related complications, such as bleeding or perforation.

CONCLUSION: APC is considered to be safe and effective for the management of SESC that cannot be resected endoscopically because of underlying disease, as well as for the control of recurrence after EMR and local recurrence after chemoradiotherapy.

Endoscopic submucosal dissection for gastric cancer

Endoscopic submucosal dissection (ESD) is a novel endoscopic treatment that enables a clinician to resect an early-stage gastric cancer in en bloc fashion. ESD is indicated for those cancers in which there is a high probability of en bloc resection and low probability of lymph node metastasis. The latter may be the limiting factor at institutions skilled at ESD. Several ESD techniques are available with similar outcomes. Thus, selection depends on operator preference and expertise. Gastrectomy with lymphadenectomy should be applied initially to those early gastric cancers with high probability of positive lymph nodes or as an additional treatment after ESD. Endoscopic mucosal resection (EMR) should be reserved for small, nonulcerated, intramucosal, differentiated cancers. Disadvantages of ESD in comparison with EMR are longer operation times and higher incidences of intraoperative bleeding and perforation, but the indication for ESD includes larger and ulcerative lesions not amenable to EMR.

Treatment of gastric epithelial tumours by endoscopic submucosal dissection using an insulated-tip diathermic knife

BACKGROUND

Endoscopic submucosal dissection (ESD) is a promising technique for the treatment of large, pre- and early malignant gastrointestinal lesions.

OBJECTIVE

To assess the rates of en bloc resection, incidence of complications, procedure times and therapeutic outcomes of ESD using an insulated-tip diathermic knife; and to investigate predictors of these outcomes based on the final pathological features of biopsy specimens.

METHODS

One hundred twenty patients with endoscopically suspected gastric epithelial tumours who were treated with ESD from January 2006 to December 2009 were evaluated.

RESULTS

The mean diameter of the gastric epithelial tumours in the present cohort was 1.88 cm. The mean diameter of the resected specimens was 3.33 cm. The en bloc resection rate was 90% (108 of 120). The median length of the operation was 64.6 min. The bleeding and perforation complication rates were 5.0% (six of 120) and 2.5% (three of 120), respectively. Of 10 gastric tumours initially diagnosed as adenocarcinoma on biopsy, four were found to be low-grade dysplasia and six were found to be high-grade dysplasia after resection and final pathological examination. A total of 112 (93.33%) patients underwent curative treatment, eight patients (6.67%) underwent noncurative treatment with ESD, and two patients (1.67%) experienced local recurrence and subsequently underwent surgery.

CONCLUSIONS

ESD is a promising local curative treatment option for gastric epithelial tumours, but still carries the risks of bleeding and⁄or perforation. Differences in the interpretation of histological results among different pathologists and⁄or between biopsy specimens before ESD and the en bloc tissue specimens after ESD will result in discrepancies.

Predictive factors for local recurrence after endoscopic resection for early gastric cancer: long-term clinical outcome in a single-center experience

BACKGROUND

Endoscopic resection is widely accepted as the primary treatment for early gastric cancer (EGC) without lymph node metastasis. A new and refined technique, endoscopic submucosal dissection (ESD), may prove to be more effective; however, incomplete resection and local recurrence present ongoing concerns. We sought to determine the clinicopathological features associated with local recurrence in patients with EGC following endoscopic resection.

METHODS

We enrolled in this study 239 EGC patients treated by endoscopic resection between January 2002 and January 2008.

RESULTS

Fifty EGC lesions were treated by conventional endoscopic mucosal resection (EMR group) and 189 EGC lesions were treated by ESD (ESD group). During the follow-up period (mean = 30.3 months), the rates for en bloc resection and complete resection (defined as en bloc resection with negative resection margin) were 64% (32/50) and 60% (30/50), respectively, in the EMR group, and 86.8% (164/189) and 79.9% (151/189), respectively, in the ESD group. We observed seven local recurrences in the ESD group, though only one with complete resection by ESD had a local recurrence. The EMR group showed a significantly higher recurrence rate than did the ESD group (18% vs. 3.7%, respectively, p < 0.001). Incomplete resection significantly increased local recurrence risk, and larger tumor size and use of EMR increased the risk for incomplete resection. Most lesions (3/4) treated with additional argon plasma coagulation for an initial recurrence had recurred again.

CONCLUSIONS

Despite the potential advantages in treating EGC with ESD, a risk for local recurrence remains. All patients treated with EMR, even with curative resection, and those with incomplete resection after ESD require conscientious surveillance for local recurrence. Furthermore, a large prospective study will be required to determine the best treatment modality for local recurrence.

Argon plasma coagulation with submucosal saline injection for gastric adenoma on outpatient basis

Gastric adenoma with low-grade dysplasia (LGD) is a less progressive disease than with high-grade dysplasia; nevertheless, a certain portion of lesions can progress. The purpose of this study was to evaluate the effectiveness of argon plasma coagulation (APC) with submucosa saline injections (APC-SSI) for gastric adenoma with LGD on an outpatient department (OPD) basis. We included 57 patients with 64 lesions of gastric adenoma with LGD. Endoscopic type was flat elevated in 58 lesions and central depressed in 6 lesions. Normal saline was injected into the submucosa under the lesion before APC. APC was performed to the lesion and its surrounding mucosa. After treatment, patients underwent regular endoscopy follow-ups. One case each of pneumoperitoneum and Mallory-Weiss tearing occurred and could be managed with conservative care. One case of overt bleeding occurred after 2 weeks and was treated with APC. After 19.5 months of follow-up, four residual adenomas (6.3%) were found and treated with additional APC-SSI. Fourteen metachronous lesions were noted in eight patients (14.0%). Twelve lesions were adenoma with LGD and two lesions were intramucosal adenocarcinoma. APC-SSI is an effective and safe treatment modality for gastric adenoma with LGD on an OPD basis and it is recommended for patients with risk factors of endoscopic mucosal resection (EMR). After treatment of gastric adenoma, meticulous follow-up endoscopy is recommended for detection of metachronous lesions.

Investigation of the thermal tissue effects of the argon plasma coagulation modes "pulsed" and "precise" on the porcine esophagus, ex vivo and in vivo

BACKGROUND

Argon plasma coagulation (APC) is a monopolar, noncontact, thermal procedure that is widely used in therapeutic endoscopy. Systematic investigations of the tissue damage ex vivo and in vivo with the new, second-generation APC modes are lacking.

OBJECTIVE

The aim of this study is to compare the tissue effects of the pulsed effect 2 and precise APC modes.

DESIGN AND SETTING

Ex vivo and in vivo animal model.

SUBJECTS

This study involved 3 explanted porcine esophagi and 8 pigs under general anesthesia.

INTERVENTION

APC application on 3 explanted esophagi and during esophagoscopy.

MAIN OUTCOME MEASUREMENTS

The tissue effect was subjected to histological and statistical investigation.

RESULTS

In vivo, a well known type of superficial tissue damage (type A) of the tunica mucosa and a new injury pattern (type B) limited to the tunica muscularis, were found. Ex vivo, only type A injuries were seen. Thermal injury of the tunica muscularis was significantly lower with precise APC compared with pulsed APC in vivo. The pulsed effect 2 shows a positive correlation between the penetration depth and the power (r = 0.38, P < .0002) or application time for the highest power setting used (40 W, r = 0.77, P < .0001). This correlation could not be detected with precise APC because of its very superficial tissue effect.

LIMITATIONS

This was an animal study. The distance of the APC probe to the esophagus may have varied between applications in vivo.

CONCLUSION

Thermal damage by APC of the esophageal tunica muscularis seems to be underestimated ex vivo. The extent of tissue injury was significantly lower with precise APC than with pulsed APC, indicating that precise APC may be suitable for the treatment of particularly thermosensitive, thin-wall anatomy.

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.

Treatment of gastrointestinal diseases with second-generation argon plasma coagulation: an analysis of 260 cases

AIM: To investigate the safety and efficacy of the second-generation argon plasma coagulation (VIO APC) for gastrointestinal diseases.

METHODS: During 2007-09-14/2008-10-22, 260 patients were treated using VIO APC in a total of 289 sessions. For various indications, the new VIO APC device was used. Safety and efficacy of VIO APC were recorded after each individual treatment session.

RESULTS: The mean number of treatment sessions required using VIO APC in various indications was 1.11 ± 0.31. In the palliative treatment of gastric adenocarcinoma, it was 2.50; in endoscopic hemostasis, it was 1.23; in the treatment of colorectal polypi, it was 1.15, in the treatment of upper gastrointestinal polypi, it was 1.03, in the management of self-expand stent overgrowth or tumor stenosis, it was 1.17; in the ablation of Barrett's esophagus, it was 1.13; in the ablation of gastric dysplasia, gastritis verrucosa, gastric xanthelasma and gastric or duodenal liparomphalus, only 1 session was needed. Minor complications (pain, dysphagia/odynophagia, asymptomatic gas accumulation in the intestinal wall) were observed in 10.1%-20% sessions, but no major complications (hemorrhage, perforation, stenosis) were observed.

CONCLUSION: VIO APC is effective and safe for various gastrointestinal conditions. It can be widely applied to daily endoscopic treatment.

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.

Long-term results of endoscopic resection in early gastric cancer: the Western experience

OBJECTIVES

In the West, neither acute nor long-term results of endoscopic resection (ER) for early gastric cancer (EGC) have been reported in large studies. The aim of this study was to prospectively evaluate the efficacy and safety of ER in patients with EGC in a long-term follow-up (FU).

METHODS

From May 1995 to October 2004, 179 patients were referred to our department for endoscopic therapy (ET) of gastric cancer (GC). Of these, 43 patients had intramucosal GC with a diameter of up to 30 mm and underwent ER with curative intent. All patients underwent a strict FU protocol at regular intervals.

RESULTS

Of the 43 patients, 42 fulfilled our low-risk criteria for ET of EGC: gross tumor type I/II, intramucosal GC, diameter up to 30 mm, tumor differentiation G1/G2, and no infiltration into lymph vessels/veins. Two patients were not available for FU (remission status not evaluated). In another patient, gastric mucosa-associated lymphoid tissue lymphoma was detected simultaneously, and he was referred for surgery. 38 (97%) of the remaining 39 patients who underwent definitive ET (23 males (59%); mean age 69+/-10 years) achieved complete remission (CR) after a mean of 1.3+/-0.6 ER sessions. Minor complications (not Hb-relevant bleeding) occurred in 7 of the 39 patients (18%) and major complications (5 Hb-relevant bleeds, 1 covered perforation; all managed conservatively) in 6 patients (15%). During FUs (mean 57 months; range 5-137), recurrent or metachronous lesions were observed in 11 patients (29%). All lesions were successfully treated by repeated ET. No tumor-related deaths occurred during FU.

CONCLUSIONS

Although ER for EGC in Western countries is effective, it is associated with a relevant risk of complications. In view of the possibility of recurrent or metachronous neoplasia, a strict FU protocol is mandatory.

Endoscopic submucosal dissection for locally recurrent colorectal lesions after previous endoscopic mucosal resection

PURPOSE

The objective of this study was to determine the efficacy and safety of endoscopic submucosal dissection for locally recurrent colorectal cancer after previous endoscopic mucosal resection.

METHODS

A total of 16 patients with locally recurrent colorectal lesions were enrolled. A needle knife, an insulated-tip knife and a hook knife were used to resect the lesion along the submucosa. The rate of the curative resection, procedure time, and incidence of complications were evaluated.

RESULTS

Of 16 lesions, 15 were completely resected with endoscopic submucosal dissection, yielding an en bloc resection rate of 93.8 percent. Histologic examination confirmed that lateral and basal margins were cancer-free in 14 patients (87.5 percent). The average procedure time was 87.2 +/- 60.7 minutes. None of the patients had immediate or delayed bleeding during or after endoscopic submucosal dissection. Perforation in one patient (6.3 percent) was the only complication and was managed conservatively. The mean follow-up period was 15.5 +/- 6.8 months; none of the patients experienced lesion residue or recurrence.

CONCLUSIONS

Endoscopic submucosal dissection appears to be effective for locally recurrent colorectal cancer after previous endoscopic mucosal resection, making it possible to resect whole lesions and provide precise histologic information.

Effectiveness of radical surgery after incomplete endoscopic mucosal resection for early colorectal cancers: a clinical study investigating risk factors of residual cancer

The aim of this study was to determine the need for additional treatment following endoscopic mucosal resection for early colorectal cancer. Risk factors for residual carcinoma were investigated using specimens of curative surgical resection performed after endoscopic mucosal resection. A total of 44 patients who had received imperfect endoscopic mucosal resection initially for early colorectal cancers and, therefore, had undergone subsequent surgical resection were enrolled in this study. Of these, 39 (88.6%) were resected completely by endoscopic mucosal resection based on gross inspection, while the other five cases (11.4%) were incompletely resected. Histopathological examination of specimens of endoscopic mucosal resection revealed that microscopic lateral resection margin was positive in 11 cases (25.0%) and vertical resection margin was positive in 16 cases (36.4%). However, after curative surgery, residual cancer within colorectal tissue was found in only five cases (11.4%), while lymph node metastases were found in three cases (6.8%). Gross incomplete resection (P < 0.001) and microscopic vertical margin positivity (P = 0.031) were found to be risk factors of residual cancer within the colorectal tissue, whereas lymphovascular invasion was a risk factor for lymph node metastasis (P = 0.040). However, no residual cancer cells were found after supplementary surgery in the microscopic lateral resection margin-positive cases. In conclusion, grossly incomplete resection, microscopic vertical resection margin positivity, or the presence of lymphovascular invasion after endoscopic mucosal resection for early colorectal cancer indicate the need for further treatment with surgical resection and lymph node dissection. However, microscopic lateral margin positivity without gross remnant tumor and deep submucosal invasion might not indicate residual cancer. This needs to be further validated by a large scale, prospective study with long-term follow-up.

Submucosal Injection of Normal Saline can Prevent Unexpected Deep Thermal Injury of Argon Plasma Coagulation in the in vivo Porcine Stomach

BACKGROUND/AIMS

There have been several reports of thermal injury induced by argon plasma coagulation (APC) in animal models, but no follow-up studies have revealed the actual thermal injury.

METHODS

APC was performed on the stomachs of two living minipigs with and without prior submucosal injection of normal saline. The power and argon gas flow were set to 60 watts and 2 L/min, respectively, and pulse durations of 5, 10, and 20 seconds were used. One of the minipigs was killed immediately thereafter and the other was killed 1 week later.

RESULTS

The minipig killed immediately showed only subtle differences between noninjected and injected injuries under all the conditions, and the usefulness of prior submucosal injection was not obvious. However, the minipig killed 1 week later had a deep ulcer extending to the deeper muscle layer at the noninjected site where APC had been applied for 20 seconds, whereas tissue injury of the injected site was limited to the submucosal layer.

CONCLUSIONS

Unexpected tissue damage can occur even using a short-duration APC. Prior submucosal injection for APC might be a safer alternative technique, especially in a thinner and narrower gut wall.

Is gastrectomy mandatory for all residual or recurrent gastric cancer following endoscopic resection? A large-scale Korean multi-center study

BACKGROUND AND OBJECTIVES

To clarify optimal treatment guidelines for residual or local recurrence after endoscopic resection (ER).

METHODS

Eighty-six patients underwent gastrectomy due to incomplete ER and local recurrence after ER. The pathological findings of ER and gastrectomy specimens were analyzed.

RESULTS

The cause of gastrectomy was categorized into five groups; submucosal (sm) invasion without margin involvement, positive margin, margin not evaluable, high risk of lymph node metastasis and local recurrence after ER. According to the pathological findings of gastrectomy specimens, remnant cancer and lymph node metastases were found in 56 (65.1%) and in 5 patients (5.8%), respectively. At 10 gastrectomy specimens which were sm invasion without margin involvement, the scattered residual cancer cells were found around the ulcer scar in 2 (20%) patients. In 11 of 44 margin involvement specimens, no residual cancer or lymph node metastasis was found. In patients with local recurrence, mean duration from ER to surgery was 14.8 months, and 19% of patients were found to have sm or deeper depth of invasion.

CONCLUSION

Gastrectomy with lymph node dissection should be performed in patients with sm invasion with or without margin involvement. However, minimal approach other than gastrectomy could further be applied to selected patients.

Long-term outcome of endoscopic semiconductive diode laser irradiation therapy with injection of indocyanine green for early gastric cancer

BACKGROUND AND AIM

Semiconductive laser irradiation has been used to treat early gastric cancer. However, the long-term follow up results have not been reported. The objective of the present study was to assess retrospectively the clinical usefulness of diode laser irradiation for early gastric cancer.

METHODS

The subjects of this study were 13 patients (14 lesions) selected from 125 patients with early gastric cancer who were treated by endoscopy during the period from September 1995 to February 2003. The macroscopic tumor type was superficial type, including eight lesions of 0'-IIc and six lesions of 0'-IIa. Histological diagnoses were eight cases (nine lesions) of well-differentiated adenocarcinoma, three cases of moderately differentiated adenocarcinoma and two cases of poorly differentiated adenocarcinoma. After injection with indocyanine green solution (1 mg/mL) into the submucosal layer, a semiconductive diode laser (30-40 W/s) was irradiated by the non-contacting method.

RESULTS

The total amount of laser irradiation for 14 lesions was 9568.80 +/- 7197.01 J on average. There was no major complication. In the period up to December 2007, six patients survived and seven patients died. However, no-one died of progression of gastric cancer. The mean survival times of all patients, survivors and patients who died were 5 years 2.8 months; 6 years 4.5 months; and 4 years 11.7 months, respectively.

CONCLUSIONS

Early gastric cancer can be successfully treated by laser therapy with few complications and good prognosis. This method is expected to be most suitable and effective for elderly patients with serious underlying disease.

Endoscopic resection for premalignant and malignant lesions of the gastrointestinal tract from the esophagus to the colon

The endoscopic mucosal resection and endoscopic submucosal dissection techniques, if performed with the right indications and with expertise, should be considered even in the West as elective treatment modalities for early gastrointestinal neoplasia. Because the experience is still limited, more should be done to strengthen the performance capacity and foster cooperation among skilled endoscopists.

Attempt of photodynamic therapy on esophageal varices

Small vessels gradually reappear within the esophageal wall after endoscopic injection sclerotherapy or endoscopic variceal ligation, which causes late recurrent bleeding. Additional ligation or a small amount of sclerotherapy of these thin and serpentine vessels is sometimes difficult to perform, and stenosis of the esophagus sometimes occurs after a small amount of sclerotherapy. In this study we attempted endoscopic photodynamic therapy on newly visible vessels and evaluated its ability to prevent recurrent bleeding. Fourteen patients with newly visible vessels within the esophageal wall were enrolled. All patients had esophageal varices secondary to hepatitis B and had their varices eliminated through endoscopic sclerotherapy before neovascularization. Seven patients received photodynamic therapy, and seven patients served as the control group. In the photodynamic therapy group, intravenous injection of 5 mg/kg of hematoporphyrin monomethyl ether was given and immediately followed by endoscopic irradiation of the newly visible vessels by copper vapor laser for 40 min with a power density of 150 mW/cm(2). Endoscopic examination was performed 3 months later to evaluate the therapeutic effect. The duration of non-bleeding was compared between the two groups. The number of newly visible vessels was found to have decreased after photodynamic therapy when compared with the control group (P < 0.001). Kaplan-Meier analyses demonstrated a longer period of non-bleeding in the photodynamic therapy group. The recurrent bleeding rate in the photodynamic therapy (PDT) group was lower than that in the control group (P = 0.027). One patient in the photodynamic therapy group suffered from facial dermatitis from shining direct light. Endoscopic photodynamic therapy seemed to be effective in the elimination of esophageal newly visible vessels and the prevention of recurrent bleeding.

Surgical indication for non-curative endoscopic resection in early gastric cancer

BACKGROUND

Endoscopic resection (ER) is an effective treatment for early gastric cancer (EGC) without lymph node metastasis. However, after ER additional surgery may be needed to manage the risks presented by residual cancer or lymph node metastasis.

METHODS

ER was performed on 344 gastric adenocarcinomas between November 2001 and April 2006 at the Korean National Cancer Center under the strict pre-procedural indication. The authors performed operations in 43 patients due to: residual mucosal cancer, a mucosal cancer larger than 3 cm, or a submucosal cancer regardless of size or margin involvement. ER and surgical specimens were reviewed and analyzed for residual cancer and lymph node metastasis.

RESULTS

Based on examinations of ER specimens, cancer was confined to the mucosal layer in 15 patients (34.9%) and invaded the submucosal layer in 28 patients (65.1%). Surgical specimens showed residual cancer in 17 patients (39.5%) and lymph node metastasis in four (9.3%). Neither residual cancer nor lymph node metastasis was found in patients with less than 500 microm submucosal invasion without margin involvement in ER specimens. In three of four patients with lymph node metastasis, the depth of submucosal invasion was 500 microm or more; the remaining patient had a 4-cm-sized differentiated mucosal cancer.

CONCLUSIONS

When a pathologic evaluation of an ER specimen reveals more than 500 microm of submucosal invasion or a mucosal cancer of larger than 3 cm, surgery should be considered due to the risk of lymph node metastasis.

Successful use of endoscopic argon plasma coagulation for patients with early gastric cancer and diabetes mellitus

We report on two patients with gastric tumors (early cancer and adema) and diabetes mellitus who were treated with argon plasma coagulation (APC) therapy. Case 1. A 78-year-old woman visited the Nippon Medical School Musashi Kosugi Hospital because of epigastric pain. An early gastric cancer (IIc) in the anterior wall of the gastric antrum was diagnosed on the basis of the results of a gastric endoscopy examination. The patient had had diabetes mellitus for 18 years and had injected insulin (NovoRapid 30 Mix, 72 units/day) by herself everyday for 10 years. Case 2. A 61-year-old man was referred to our hospital because of a gastric tumor. A gastric adenoma in the anterior of the gastric antrum was diagnosed on the basis of the results of a gastric endoscopy examination. The patient had had diabetes mellitus for 12 years and had been taking oral medication for 2 years. Endoscopic APC was performed in both patients to remove the gastric tumors. These patients have been well for 28 months and 30 months, respectively, after undergoing APC treatment. APC therapy appears to be a safe and useful treatment for patients with diabetes and gastric mucosal lesions.

Endoscopic resection of early gastric cancer

The purpose of this review is to examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer (EGC). Endoscopic mucosal resection (EMR) of EGC, with negligible risk of lymph node metastasis, is a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. EMR is a minimally invasive technique which is safe, convenient, and efficacious; however, it is insufficient when treating larger lesions. The evidence suggests that difficulties with the correct assessment of depth of tumor invasion lead to an increase in local recurrence with standard EMR when lesions are larger than 15 mm. A major factor contributing to this increase in local recurrence relates to lesions being excised piecemeal due to the technical limitations of standard EMR. A new development in endoscopic techniques is to dissect directly along the submucosal layer -- a procedure called endoscopic submucosal dissection (ESD). This allows the en-bloc resection of larger lesions. ESD is not necessarily limited by lesion size and it is predicted to replace conventional surgery in dealing with certain stages of ECG. However, it still has a higher complication rate when compared to standard EMR, and it requires high levels of endoscopic skill and experience. Endoscopic techniques, indications, pathological assessment, and methods of endoscopic resection of EGC need to be established for carrying out appropriate treatment and for the collation of long-term outcome data.

Endoscopic resection of early gastric cancer

The purpose of this review is to examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer (EGC). Endoscopic mucosal resection (EMR) of EGC, with negligible risk of lymph node metastasis, is a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. EMR is a minimally invasive technique which is safe, convenient, and efficacious; however, it is insufficient when treating larger lesions. The evidence suggests that difficulties with the correct assessment of depth of tumor invasion lead to an increase in local recurrence with standard EMR when lesions are larger than 15 mm. A major factor contributing to this increase in local recurrence relates to lesions being excised piecemeal due to the technical limitations of standard EMR. A new development in endoscopic techniques is to dissect directly along the submucosal layer -- a procedure called endoscopic submucosal dissection (ESD). This allows the en-bloc resection of larger lesions. ESD is not necessarily limited by lesion size and it is predicted to replace conventional surgery in dealing with certain stages of ECG. However, it still has a higher complication rate when compared to standard EMR, and it requires high levels of endoscopic skill and experience. Endoscopic techniques, indications, pathological assessment, and methods of endoscopic resection of EGC need to be established for carrying out appropriate treatment and for the collation of long-term outcome data.

Endoscopic submucosal dissection of early gastric cancer

The purpose of this review was to examine a remarkable technical advance regarding the indications for and the technique of endoscopic resection of early gastric cancer. Endoscopic mucosal resection (EMR) of early gastric cancer with no risk of lymph node metastasis has been a standard technique in Japan, probably owing to the high incidence of gastric cancer in Japan and the fact that more than half of Japanese gastric cancer cases are diagnosed at an early stage. Very recently, several EMR techniques have become increasingly accepted and regularly used in Western countries. Although these minimally invasive techniques are safe, convenient, and efficacious, they are unsuitable for large lesions in particular. Difficulty in correctly assessing the depth of tumor invasion and an increase in local recurrence when standard EMR procedures are used have been reported in cases of large lesions, because such lesions are often resected piecemeal owing to the technical limitations of standard EMR. A new development in therapeutic endoscopy, called endoscopic submucosal dissection (ESD), allows the direct dissection of the submucosa, and large lesions can be resected en bloc. ESD is not limited by resection size and is expected to replace surgical resection. However, it is still associated with a higher incidence of complications than standard EMR procedures and requires a high level of endoscopic skill. The endoscopic indications, techniques, and management of complications of ESD for early gastric cancer for properly carrying out established therapeutic endoscopy are described.

Endoscopic resection of early gastric cancer: the Japanese perspective

PURPOSE OF REVIEW

To examine recent advances in the techniques and technologies of endoscopic resection of early gastric cancer.

RECENT FINDINGS

Endoscopic mucosal resection of early gastric cancer with no risk of lymph node metastasis has been a standard technique in Japan and is increasingly becoming accepted and regularly used in Western countries. Though this minimally invasive technique is a safe, convenient and efficacious method, it is insufficient for larger lesions. Difficulties in correctly assessing the depth of tumour invasion and increases in local recurrence by standard endoscopic mucosal resection have been reported in lesions larger than 15 mm. This is because such lesions are often resected piecemeal due to the technical limitation of standard endoscopic mucosal resection. New developments in endoscopic resection techniques to dissect the submucosa directly, called endoscopic submucosal dissection, allows resections of larger lesions en bloc. There are no limitations in resection size in endoscopic submucosal dissection, which is expected to replace surgery. This technique, however, still has higher complications rates than standard endoscopic mucosal resection and requires highly skilled endoscopists.

SUMMARY

The techniques, indications, and pathological assessment methods of endoscopic resection of early gastric cancer are described so that proper treatment guidelines can be established and long-term outcome data can be assessed.