Foreword

Dear colleagues and friends,

This issue comprises 11 original articles, 1 case report and 4 editorials. We first have a large series (78 cases) of a rare but well-known esophageal condition, the esophageal squamous papilloma. Given that the study conducted in northeast France is retrospective, the found prevalence was very low (0.01 %). Clinical and endoscopic features of esophageal papilloma are presented and discussed as well as the endoscopic follow-up in 35 patients. Esophageal ESD is no more a tricky procedure and the major complication related to esophageal ESD is not bleeding or perforation but stricture formation in case of circumferential mucosal defect. A study explains all the recent attempts to prevent post-ESD stricture. Top list is the oral administration of oral steroids as reported in this issue. The different preventive measures are discussed in an attached editorial.

Radiofrequency is for many reasons (homogenous effect and easiness) the gold standard for Barrett’s esophagus ablation. Cryotherapy using liquid nitrogen or pressurized CO₂ as cooling agent is a more recent modality of treatment and has been less evaluated. A pilot study has been conducted with pressurized CO₂ gas and has been stopped due to insufficient effect on dysplasia. The question of interest is here: Can the technique be improved or is the cooling effect with CO₂ basically insufficient?

Japanese colleagues from Ishikawa observed mainly with NBI the presence of a globular, small, white lesion located underneath superficial gastric carcinomas. This “white globe appearance” (WGA) corresponds to necrotic debris within dilated neoplastic glands, and the authors demonstrated that it is observed in almost 20 % of cases and is highly specific of cancer.

Evaluation of the HER2 status in metastatic gastric cancer (including gastroesophageal junction) is necessary to predict response to anti-HER2 agents. A study from Genoa, Italy, observes that a number of 5 biopsies is sufficient for HER2 assessment in these cases although several guidelines recommend 8 to 10.

Small subepithelial tumors (< 10 mm) are difficult to puncture under EUS control because they move. Therefore, a Japanese team from Aizuwakamatsu proposes to use a forward-puncturing (and viewing) endoscope equipped with a cap to fix the tumor.

Within few years, a considerable literature has been dedicated to the question how to improve the sensitivity of EUS FNA cytology. A paper from Germany demonstrates that one of the key factors and maybe the more important is the cytopathologist’s experience and suggests that a specialized cytopathologist on site or more frequently off-site should be involved. In an attached editorial, the different techniques and/or measures to improve sensitivity of EUS-FNA cytology are listed.

If we need to systematically heal post ESD mucosal defect is still unclear despite the fact that theoretically this could reduce post-operative bleeding, delayed perforation and above all stenosis. Several Japanese groups are exploring different techniques of healing. The limiting factor is in fact the dislodgement of the healing agent due to peristaltism or secretions.

In this issue, T Takao et al. from Shizuoka, Japan, explained how to affix polyglycolic acid sheets with fibrin glue on post-ESD gastric ulcers in pigs. Effective sheet adhesion resulted in granulation with neovessel formation. It was impossible to present such a paper in this issue without an attached editorial which discusses the role of a systematic post-ESD defect shielding.

Gastric antral vascular ectasia (GAVE) is usually treated by argon plasma coagulation (APC) for several reasons (easiness + effectiveness + low cost). Some cases are nevertheless refractory to APC. A short series demonstrates that radiofrequency application can be helpful in these cases and confirms previous data. Of course refractory GAVE has first to be well defined. An attached editorial explains the different issues related to refractory GAVE (indications, techniques).

EUS guided pseudocyst drainage has been a well established procedure for years. Nevertheless, a survey conducted by the Asian EUS group shows a high variability of practices. On one hand, more consensus is needed in this field, but on the other hand, this also reflects the fact that many different tools or tricks are now available when performing pseudocyst drainage or walled-off pancreatic necrosis. For example, in this EIO issue, endoscopic drainage of walled-off pancreatic stenosis was conducted in 17 patients by combining fully-covered metal stenting to gain access to the cavity and high-flow water jet to clean the cavity.

Real-time characterization of colorectal polyps generates multiple recent publications. It is not surprising that magnification (X80) can increase the rates of high confidence NBI-based optical diagnosis of diminutive and small colorectal polyps, as it is reported in this issue by a Japanese team assisted by American and Australian experts (one major limitation of this study is that the diagnosis was made by the same operator using first non-magnified and then magnified endoscope). The question is if we should promote magnification in routine practice for polyp characterization as it is not popular in western countries and requires some expertise and dedication as demonstrated in this series.

Thierry Ponchon, MD

Editor-in-Chief, Endoscopy International Open