Prospective evaluation of a new high-power argon plasma coagulation system (hp-APC) in therapeutic gastrointestinal endoscopy

Endoscopic management of superficial nonampullary duodenal tumors: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends that all duodenal adenomas should be considered for endoscopic resection as progression to invasive carcinoma is highly likely.Strong recommendation, low quality evidence. 2: ESGE recommends performance of a colonoscopy, if that has not yet been done, in cases of duodenal adenoma.Strong recommendation, low quality evidence. 3: ESGE recommends the use of the cap-assisted method when the location of the minor and/or major papilla and their relationship to a duodenal adenoma is not clearly established during forward-viewing endoscopy.Strong recommendation, moderate quality evidence. 4: ESGE recommends the routine use of a side-viewing endoscope when a laterally spreading adenoma with extension to the minor and/or major papilla is suspected.Strong recommendation, low quality evidence. 5: ESGE suggests cold snare polypectomy for small (< 6 mm in size) nonmalignant duodenal adenomas.Weak recommendation, low quality evidence. 6: ESGE recommends endoscopic mucosal resection (EMR) as the first-line endoscopic resection technique for nonmalignant large nonampullary duodenal adenomas.Strong recommendation, moderate quality evidence. 7: ESGE recommends that endoscopic submucosal dissection (ESD) for duodenal adenomas is an effective resection technique only in expert hands.Strong recommendation, low quality evidence. 8: ESGE recommends using techniques that minimize adverse events such as immediate or delayed bleeding or perforation. These may include piecemeal resection, defect closure techniques, noncontact hemostasis, and other emerging techniques, and these should be considered on a case-by-case basis.Strong recommendation, low quality evidence. 9: ESGE recommends endoscopic surveillance 3 months after the index treatment. In cases of no recurrence, a further follow-up endoscopy should be done 1 year later. Thereafter, surveillance intervals should be adapted to the lesion site, en bloc resection status, and initial histological result. Strong recommendation, low quality evidence.

Hybrid Argon Plasma Coagulation for Treatment of Gastric Intestinal Metaplasia

Hybrid argon plasma coagulation (HybridAPC® [HAPC]) is an evolution of the standard argon plasma coagulation (APC) technology, where the application of APC is preceded by high-pressure needleless submucosal injection. APC is indicated for the ablation of benign and dysplastic mucosal lesions, such as vascular malformations or Barrett's mucosa. HAPC offers safety and efficacy advantages over standard APC because the submucosal injection acts as a heat sink that disperses energy. This ensures that the underlying muscularis propria remains unaffected, and only the mucosal layer is coagulated in its entirety. An 81-year-old Hispanic male was found to have a 1.2-cm mucosal nodule along the incisura of the stomach. Pathology of the biopsy specimen revealed high-grade dysplasia, and he subsequently underwent endoscopic ultrasound examination, which confirmed the presence of an isolated gastric nodule with no deep invasion of the muscularis propria, consistent with a uT1N0Mx endosonographic staging. He then underwent endoscopic submucosal dissection of the lesion. Pathology of the excised specimen confirmed the presence of multifocal high-grade dysplasia, arising in the background of extensive intestinal metaplasia. The deep margin was clear; however, the lateral resection margins showed focal involvement of intestinal metaplasia with low-grade dysplasia. Surveillance endoscopy confirmed the persistence of diffuse intestinal metaplasia. He was then treated with widespread HAPC due to the presence of underlying diffuse intestinal metaplasia in the stomach. HAPC is an effective and efficient treatment modality for mucosal lesions. In one series of 50 patients, 96% achieved complete macroscopic remission of Barrett's mucosa after a median of 3.5 APC sessions, and 85% achieved complete histological remission. HAPC is a promising therapeutic modality as a thermal injury is targeted, and the depth of injury is contained. This provides immediate procedural efficacy and safety benefits, and reduces subsequent complications when compared with standard APC. We anticipate that the applications of HAPC will continue to grow, as this modality is adopted into common procedural parlance. This case appears to be the first to describe the use of HAPC for definitive treatment of diffuse intestinal metaplasia.

Comparison of Argon Plasma Coagulation and Injection Therapy with Adrenalin and Polidocanol in the Management of Bleeding Angiodysplasia in Upper Gastrointestinal Tract

INTRODUCTION

The term angiodysplasia (AD) refers to acquired malformation of the blood vessels (communications between veins and capillaries), frequently found within the gastrointestinal mucosa and submucosa. AD of stomach and duodenum are cause of upper gastrointestinal bleeding in 4%-7% of patients. The means of treatment are usually endoscopic, including argon plasma coagulation (APC), electrocoagulation, mechanical hemostasis by clippsing, laser photo-coagulation and injection therapy.

AIM

To compare the success rate, and adverse events (ulcer lesions, perforations) of APC and injection therapy in the treatment of bleeding angiodysplasia in the upper gastrointestinal tract (GIT).

MATERIAL AND METHODS

In a prospective study including 50 patients with bleeding angiodysplasia of the upper GIT, 35 patients were treated with APC, and remaining 15 with injection therapy using adrenaline and 1.5% solution of polidocanol. Follow-up period was 6 months.

RESULTS

A total of 50 patients aged 18 to 64 years, 64% male and 36% female, have been treated during 2 years period. The rate of recurrent bleeding and side effects was significantly higher in the adrenaline group (p <0.01). Blood transfusion was required in 68% during the first hospital admission. Angiodysplasia of the stomach was present in 66%, versus 34% in duodenum.

CONCLUSION

Endoscopy is "gold standard" for diagnosis and treatment of AD in the gastrointestinal tract. The study unveiled APC as more effective treatment option with lower degree of complications and adverse events in comparison to injection therapy in patients with bleeding AD.

Argon Cold Plasma-A Novel Tool to Treat Therapy-resistant Corneal Infections

PURPOSE

To test whether therapy-resistant corneal infections can be successfully treated with argon cold plasma to reduce or eliminate pathogen microorganisms without affecting corneal cell viability.

DESIGN

First-in-human case series and experimental study.

METHODS

Cold plasma effects on viability of primary human corneal limbal epithelial cells were studied using exposure times from 0.5 to 10 minutes (metabolic activity, oxidative stress, apoptosis). Disinfective potential of cold plasma was tested against common pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans) on culture medium and evaluated by counting colony-forming units and optical density measurements, as well as against S aureus in a human cornea infection model. Additionally, in a first-in-human trial 4 patients with therapy-resistant corneal ulcers were treated to evaluate the clinical potential of cold plasma.

RESULTS

Cells treated for 0.5-5 minutes completely recovered within 24 hours without changes in morphology; only 10-minute treatment impaired the cells permanently. No evident oxidative stress, apoptosis, or damage to the corneal structure could be found. All pathogens were susceptible to cold plasma treatments, with different levels of sensitivity. The condition of all 4 patients significantly improved after cold plasma treatment combined with antibiotic therapy.

CONCLUSIONS

Our results indicate that argon cold plasma treatment reduces or eliminates common pathogens without impairing corneal epithelial cells in vitro, ex vivo, and in direct application on patients' eyes. We conclude that argon cold plasma therapy offers a potential supplement or alternative therapy for therapy-resistant corneal infections. A larger, comparative study is necessary to further confirm these findings.

Epidemiology, Diagnosis, and Management of Esophageal Adenocarcinoma

Esophageal adenocarcinoma (EAC) is rapidly increasing in incidence in Western cultures. Barrett's esophagus is the presumed precursor lesion for this cancer. Several other risk factors for this cancer have been described, including chronic heartburn, tobacco use, white race, and obesity. Despite these known associations, most patients with EAC present with symptoms of dysphagia from late-stage tumors; only a small number of patients are identified by screening and surveillance programs. Diagnostic analysis of EAC usually commences with upper endoscopy followed by cross-sectional imaging. Endoscopic ultrasonography is useful to assess the local extent of disease as well as the involvement of regional lymph nodes. T1a EAC may be treated endoscopically, and some patients with T1b disease may also benefit from endoscopic therapy. Locally advanced disease is generally managed with esophagectomy, often accompanied by neoadjuvant chemoradiotherapy or chemotherapy. The prognosis is based on tumor stage; patients with T1a tumors have an excellent prognosis, whereas few patients with advanced disease have long-term survival.

Efficacy and safety of Hybrid-APC for the ablation of Barrett's esophagus

BACKGROUND AND STUDY AIM

After thermal ablation of Barrett's esophagus (BE), stricture formation is reported in 5 to over 10% of patients. The question arises whether submucosal fluid injection prior to ablation may lower the risk of stricture formation. The aim of the present study was to evaluate the efficacy and safety of the new technique of Hybrid-APC which combines submucosal injection with APC.

PATIENTS AND METHODS

Patients who had a residual BE segment of at least 1 cm after endoscopic resection of early Barrett's neoplasia underwent thermal ablation of BE by Hybrid-APC. Prior to thermal ablation, submucosal injection of sodium chloride 0.9% was carried out using a flexible water-jet probe (Erbejet 2; Erbe Elektromedizin, Tuebingen, Germany). Check-up upper GI endoscopy was carried out 3 months after macroscopically complete ablation including biopsies from the neo-Z-line and the former BE segment, and recording of stricture formation.

RESULTS

From May 2011 to November 2012, a total of 60 patients (pt) were included in the study [55 pt male (92%); mean age 62 ± 9 years, range 42-79]. Ten patients were excluded from the study. In the remaining 50 pt, Hybrid-APC ablation and check-up endoscopy at 3 months were carried out. Forty-eight out of 50 pt (96%; ITT: 49/60, 82%) achieved macroscopically complete remission after a median of 3.5 APC sessions [SD 2.4; range 1-10]. Freedom from BE was histopathologically observed in 39/50 patients (78%). There was one treatment-related stricture (2%). Minor adverse events of Hybrid-APC were observed in 11 patients (22%).

CONCLUSIONS

According to this pilot series, Hybrid-APC was effective and safe for BE ablation in a tertiary referral center. The rate of stricture formation was only 2%. Further studies are required to confirm the present results.

GERMAN CLINICAL TRIALS REGISTER

DRKS00003369.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Zenker's Diverticulum

Zenker's diverticulum (ZD) is an outpouching of tissue through the Killian triangle that is believed to be caused by dysfunction of the cricopharyngeal muscle. ZD is a relatively uncommon disorder occurring in the elderly. The predominant symptom of ZD is dysphagia, and the most serious consequence is pulmonary aspiration. Videofluoroscopy confirms the diagnosis. Therapy of symptomatic ZD has evolved from an open surgical approach to less invasive transoral endoscopic techniques. Transoral endoscopic therapy using rigid instruments is performed primarily by otorhinolaryngologists, whereas transoral therapy using flexible endoscopes is performed by surgical endoscopists and gastroenterologists. The common goal of all modalities is severing of the septum between the esophageal lumen and the diverticulum containing the cricopharyngeal muscle. Although flexible endoscopic therapy was described nearly 20 years ago, it has experienced a recent resurgence paralleling the advancements of therapeutic endoscopy in other areas, such as endoscopic submucosal dissection. Direct head-to-head comparisons of rigid and flexible endoscopic therapy are lacking, and each approach has variations in techniques as well as advantages and disadvantages. In this article, we review the pathophysiology and management of patients with ZD with an emphasis on flexible endoscopic therapy.

The tissue effect of argon-plasma coagulation with prior submucosal injection (Hybrid-APC) versus standard APC: A randomized ex-vivo study

BACKGROUND

Thermal ablation for Barrett's oesophagus has widely been established in gastrointestinal endoscopy during the last decade. The mainly used methods of radiofrequency ablation (RFA) and argon-plasma coagulation (APC) carry a relevant risk of stricture formation of up to 5-15%. Newer ablation techniques that are able to overcome this disadvantage would therefore be desirable. The aim of the present study was to compare the depth of tissue injury of the new method of Hybrid-APC versus standard APC within a randomized study in a porcine oesophagus model.

METHODS

Using a total of eight explanted pig oesophagi, 48 oesophageal areas were ablated either by standard or Hybrid-APC (APC with prior submucosal fluid injection) using power settings of 50 and 70 W. The depth of tissue injury to the oesophageal wall was analysed macroscopically and histopathologically.

RESULTS

Using 50 W, mean coagulation depth was 937 ± 469 µm during standard APC, and 477 ± 271 µm during Hybrid-APC (p = 0.064). Using 70 W, coagulation depth was 1096 ± 320 µm (standard APC) and 468 ± 136 µm (Hybrid-APC; p = 0.003). During all settings, damage to the muscularis mucosae was observed. Using standard APC, damage to the submucosal layer was observed in 4/6 (50 W) and 6/6 cases (70 W). During Hybrid-APC, coagulation of the submucosal layer occurred in 2/6 (50 W) and 1/6 cases (70 W). The proper muscle layer was only damaged during conventional APC (50 W: 1/6; 70 W: 3/6).

LIMITATIONS

Ex-vivo animal study with limited number of cases.

CONCLUSIONS

Hybrid-APC reduces coagulation depth by half in comparison with standard APC, with no thermal injury to the proper muscle layer. It may therefore lead to a lower rate of stricture formation during clinical application.

Efficacy and safety of endoscopic treatment for nonampullary sporadic duodenal adenomas

BACKGROUND

Nonampullary sporadic duodenal adenomas (NSDAs) are uncommon mucosal neoplasms with malignant potential. Recently, endoscopic treatment is used for NSDA with increasing frequency.

AIMS

This study therefore aimed to evaluate the efficacy and safety of endoscopic treatment for NSDA.

METHODS

A total of 36 NSDAs in 35 consecutive patients were endoscopically eradicated at Samsung Medical Center between October 1994 and May 2011. Data on patient demographics, tumor characteristics, and endoscopic treatment outcomes were obtained and retrospectively analyzed.

RESULTS

Of all patients, 19 (52.8 %) were male. The mean age was 56.0 ± 12.2 (SD) years. Of the 36 NSDAs, 23 lesions were removed by endoscopic resection (ER) including endoscopic mucosal resection (EMR, n = 20) and snare polypectomy (n = 3). In the 23 cases treated with ER, en bloc resection was achieved in 20 (87.0 %). All cases undergoing en bloc resection showed tumor-free resection margins. Thirteen lesions were ablated by argon plasma coagulation (APC). During EMR, bleeding occurred in two cases and perforation occurred in one case. One patient bled during APC. All complications were successfully managed with endoscopic treatment without surgical intervention. During a median follow-up period of 11.4 months (range, 1.8-182.4 months), local recurrence occurred in one patient treated with APC (1/10, 10.0 %). Among patients undergoing ER, no local recurrence occurred but one patient treated with EMR experienced metachronous recurrence.

CONCLUSIONS

Endoscopic treatment, including EMR, snare polypectomy, and APC, was an effective and safe treatment for NSDA. Further multi-center large prospective studies are warranted to establish appropriate treatment guidelines for NSDA.

Radiofrequency ablation offers a Reliable Surgical Modality for the Treatment of Barrett's Esophagus with a Minimal Learning Curve

Radiofrequency ablation (RFA) has gained popularity as treatment for Barrett's esophagus. Inclusive series of patients from initiation of our Barrett's Therapy Program were studied. Review of patients undergoing RFA for Barrett's was performed from September 2008 to May 2011. Patients’ outcomes were recorded and analyzed using standard statistical methods. Seventy patients were treated. Average age was 61 (28–70); 80 per cent were male. Seventy-four per cent had dysplasia; 44 low-grade and eight high-grade. A total of 75.7 per cent of patients had long and 24.3 per cent had short segment Barrett's. Procedures per patient ranged from one to seven. Number of treatments in long- and short-segment groups were not different ( P = 0.11). The maximum number of treatments in the short-segment group was five with a median of three (44.3%). For long segment, the maximum of RFA procedures was seven, with a median of three (30.8%). Average procedure time was 20.8 minutes for long and 17.9 minutes for short segment. Mean follow-up was 16.1 (2–38) months. Complete response was accomplished in 81 per cent. There were 93.3 per cent of complete responders in the short-segment group versus 75 per cent in the long ( P = 0.24). Complications included dysphagia (1), transient chest and cervical pain (1), and abdominal pain (1). Comparing the first 25 per cent of the RFA procedures to the later 75 per cent or first 50 per cent to second 50 per cent, there was no difference in operative time or complications. Two patients recurred, both in the long-segment group. RFA is a safe and effective means to eradicate Barrett's. By measure of treatment time, complication rate, and efficacy of therapy, there is minimal or no “learning curve” for experienced endoscopists.

Endoscopic treatments for Barrett's esophagus: a systematic review of safety and effectiveness compared to esophagectomy

BACKGROUND

Recently, several new endoscopic treatments have been used to treat patients with Barrett's esophagus with high grade dysplasia. This systematic review aimed to determine the safety and effectiveness of these treatments compared with esophagectomy.

METHODS

A comprehensive literature search was undertaken to identify studies of endoscopic treatments for Barrett's esophagus or early stage esophageal cancer. Information from the selected studies was extracted by two independent reviewers. Study quality was assessed and information was tabulated to identify trends or patterns. Results were pooled across studies for each outcome. Safety (occurrence of adverse events) and effectiveness (complete eradication of dysplasia) were compared across different treatments.

RESULTS

The 101 studies that met the selection criteria included 8 endoscopic techniques and esophagectomy; only 12 were comparative studies. The quality of evidence was generally low. Methods and outcomes were inconsistently reported. Protocols, outcomes measured, follow-up times and numbers of treatment sessions varied, making it difficult to calculate pooled estimates.The surgical mortality rate was 1.2%, compared to 0.04% in 2831 patients treated endoscopically (1 death). Adverse events were more severe and frequent with esophagectomy, and included anastomotic leaks (9.4%), wound infections (4.1%) and pulmonary complications (4.1%). Four patients (0.1%) treated endoscopically experienced bleeding requiring transfusions. The stricture rate with esophagectomy (5.3%) was lower than with porfimer sodium photodynamic therapy (18.5%), but higher than aminolevulinic acid (ALA) 60 mg/kg PDT (1.4%). Dysphagia and odynophagia varied in frequency across modalities, with the highest rates reported for multipolar electrocoagulation (MPEC). Photosensitivity, an adverse event that occurs only with photodynamic therapy, was experienced by 26.4% of patients who received porfimer sodium.Some radiofrequency ablation (RFA) or argon plasma coagulation (APC) studies (used in multiple sessions) reported rates of almost 100% for complete eradication of dysplasia. But the study methods and findings were not adequately described. The other studies of endoscopic treatments reported similarly high rates of complete eradication.

CONCLUSIONS

Endoscopic treatments offer safe and effective alternatives to esophagectomy for patients with Barrett's esophagus and high grade dysplasia. Unfortunately, shortcomings in the published studies make it impossible to determine the comparative effectiveness of each of the endoscopic treatments.

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.

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.

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.

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.

Argon plasma coagulation therapy

PURPOSE OF REVIEW

To give a summary of recent advances in argon plasma coagulation (APC) therapy in gastroenterology.

RECENT FINDINGS

APC has gained importance in gastrointestinal endoscopy during the last decade, and APC technology has improved over time. Recently published studies, mainly consisting of case series, have shown that APC can be used effectively in various forms of gastrointestinal disorders. The complication rates observed during clinical application are low.

SUMMARY

APC can be considered as a well tolerated and effective treatment approach in endoscopy. Further clinical trials including a comparison of APC to other treatment modalities as well as long-term follow-up after APC treatment are required to clarify the relative value of APC in gastroenterology.

Second-generation argon plasma coagulation: two-center experience with 600 patients

BACKGROUND AND AIM

Second-generation argon plasma coagulation (APC; APC 2/VIO APC) with its modes 'forced', 'pulsed', and 'precise' is a further development of the ICC/APC 300 system (first-generation APC). Until now, only limited data has existed on the use of APC 2.

METHODS

Fundamental data on the characteristics of the various APC 2 modes and clinical data from more than 600 patients treated in two high-volume endoscopy centers were analyzed. On the basis of these data, recommendations for the use of APC in daily gastroenterological practice were made.

RESULTS

In comparison to the ICC system, second-generation APC offers a broadened bandwidth of settings including different APC modes and a range of power settings from 1 to 120 W. Using the various modes of APC 2 in a variety of gastrointestinal diseases, minor complications were observed in 9-21% of patients. Major complications occurred in 1-7% of patients.

CONCLUSIONS

In a two-center experience treating a large group of patients with a wide variety of gastrointestinal conditions, the different APC 2 modes appeared to be safe and effective. Certain preventive measures before and during clinical application are recommended in order to avoid complications.

Multifocal neoplasia and nodal metastases in T1 esophageal carcinoma: implications for endoscopic treatment

OBJECTIVE

There has been an increase in interest in endoscopic therapy (ET) for intramucosal (T1a) or submucosal (T1b) esophageal carcinoma. The objective of the present study was to determine the prevalence of nodal metastases, lymphatic vascular invasion, and multifocal neoplasia in patients with pT1 esophageal carcinoma who underwent esophagectomy without preoperative therapy and assess their potential implication for ET.

METHODS

We retrospectively reviewed the records of all patients who underwent esophagectomy without preoperative therapy for pT1 esophageal cancer. A detailed review of all pathology reports was performed to identify relevant pathologic criteria including depth of invasion (T1a or T1b), cell type (adenocarcinoma/squamous), tumor differentiation (poor vs. well/moderate), extent of Barrett esophagus (short segment [SSBE] and long segment [LSBE]), nodal status, lymphovascular invasion (LVI), and the presence of multifocal neoplasia (MFN) (high-grade dysplasia or invasive carcinoma). Overall survival and disease-specific survival were determined by the Kaplan-Meier method.

RESULTS

There were 75 consecutive patients (58 men, 17 women) between January 1994 and September 2006. Median age was 68 years. Hospital mortality was 2.6% (2 of 75). Thirty patients had T1a and 45 had T1b. Sixty patients had adenocarcinoma. Nodal metastases were present in 2 of 30 (6%) T1a and 8 of 45 (17.5%) T1b tumors. MFN was present in 30% (9 of 30) of T1a tumors and 29% (13 of 45) of T1b tumors. All 9 patients with LVI had T1b tumors. Collectively, 10 of 30 (33.3%) patients with T1a and 25 of 45 (58%) with T1b had MFN, LVI, or nodal metastases. Forty-nine patients had adenocarcinoma with associated BE (23 SSBE, 26 LSBE). There was no difference between patients with SSBE and those with LSBE in the incidence of nodal disease (2 of 23 vs. 2 of 26) but a significant difference in the incidence of MFN (3 of 23 vs. 13 of 26, P = 0.006). Four patients with squamous carcinoma had nodal metastases and 5 had MFN. Overall 5-year survival was 78% (T1a:90% T1b: 71%, P = 0.07). Five-year disease-specific survival was 86.5% (T1a: 96.7%, T1b: 79.6%, P = 0.06).

CONCLUSION

The combined high incidence of MFN, LVI, and occult nodal metastases does not support the use of ET in patients with T1 esophageal cancer regardless of depth of invasion, cell type, differentiation or extent of BE. ET may be of value in patients in whom surgical risk is considered prohibitive.