Introduction: Innovation Forum

The aim of the Innovation Forum is to present new and special techniques that are at various stages of development, ranging from animal experiments to case series at single centers in which the technique was developed. The diagnostic and therapeutic techniques presented share the common features in that they offer interesting and challenging approaches and that they have not reached the status of being fully clinically assessed. They are not yet state-of-the-art techniques in certain clinical situations, but may well become so in the future.

This new feature was born out of our “Expert Approach” section. When looking for new and interesting techniques to be presented in this section, we felt that a new section should be created to allow presentation of new and exciting techniques. These may not have yet reached evidence levels to allow them to be recommended generally in clinical practice, or to suggest that everybody should be taught how to carry them out. However, some of these new techniques are often very innovative and stimulating, and they may open up new horizons for the further development of GI endoscopy and/or require a high degree of expertise. Often these techniques are still under development and have only been tested in animals. In many instances, they are also being developed in cooperation with, or have been entirely developed by, the biomedical industry. For these reasons, this new section does not have a predetermined format in the way the Expert Approach section has. We hope our readers enjoy this new feature in Endoscopy.

In this issue of Endoscopy, the presentation by Makuuchi and colleagues is the first in this series. The endoscopic treatment of neoplastic lesions in the digestive tract is increasingly becoming accepted as an elective procedure for superficial lesions, even with minimal invasion into the submucosa. Safe threshold values for endoscopic treatment have been established. The extent of submucosal invasion should be less than 200 µm in the esophagus, 500 µm in the stomach, and 1000 µm in the colon. Strict guidelines apply to the choice between surgical or endoscopic treatment and to the methodology used and control of the procedure. Notably, a higher rate of complete cure after endoscopic mucosectomy is achieved when a single fragment can be resected (en-bloc resection), rather than using the piecemeal technique. In addition, the resection must be absolutely complete in order to prevent local recurrences.

With small lesions, strip mucosectomy is a simple procedure in which snare resection is facilitated by the submucosal injection of saline and aspiration with a cap. This procedure deserves to be in widespread use by every endoscopist who carries out polypectomies. En-bloc endoscopic resection of large lesions involves a greater degree of complexity. Classified as a form of minimally invasive surgery, this procedure requires special training and is only carried out in specialized units in which contact with the surgical department is maintained and there is strict observance of the surgical protocol. There is an increased risk of complications (perforation or hemorrhage) with this more complex type of endoscopic resection, and the operator should be trained to prevent and treat such complications. Two categories of procedure, which are likely to undergo further development in the future, are used:

Procedures based on dissection of the submucosa use the endoscopic equivalent of a surgical knife, the simple needle-knife, which is likely to be replaced by other less aggressive instruments such as the hook knife or insulated-tip knife. Most of these procedures involve the treatment of neoplasia in the stomach. Procedures in which an accessory tube is used offer better access to the lesion, with the accessory channel being used to introduce a snare or traction forceps. Most of these procedures involve the treatment of neoplasia in the esophagus.

The paper by Makuuchi and colleagues is a good example of a rigorous technique divided into four successive steps. En-bloc resection of the major part of the lesion is followed by three steps with a decreasing order of aggressiveness. This ensures the reliability of complete resection and control of the risk of complications. This high-quality procedure should certainly only be carried out by skilled and experienced endoscopists.