Underwater vs. Conventional Endoscopic Submucosal Dissection: Retrospective Analysis from a German High-Volume Center

Abstract

Background

Endoscopic submucosal dissection (ESD) is an established technique for the resection of early neoplasia in the gastrointestinal tract (GIT). A further development of this technique is the resection under isotonic saline solution (underwater ESD or uESD), also referred to as Saline Immersion Therapeutic Endoscopy (SITE). Potential advantages include faster submucosal access and a reduced rate of intraprocedural complications, particularly submucosal bleeding. The primary objective of this retrospective, single-centre analysis was to provide the first data from Germany concerning the efficacy and safety of uESD and compare it to conventional ESD (cESD).

Methods

This retrospective study analysed data from patients who underwent either uESD (n=36) or cESD (n=36). The control group (cESD) included lesions of similar location and size. Lesion selection was validated using propensity score matching. Treatment duration, complication rate, en-bloc resection rate, R0 resection rate, and recurrence rate were compared.

Results

A total of 72 ESD procedures were performed in 72 patients (36 undergoing uESD and 36 cESD). Per group, 11 procedures were performed in the esophagus, 3 in the stomach, 16 in the colon and 6 in the rectum. The median lesion size was 40 × 30 mm for uESD and 45 × 30 mm for cESD (p = 0.653). The median procedure time was similar (uESD: 77 minutes, cESD: 75 minutes, p = 0.088). The en-bloc resection rate was 100% in both groups, and the R0 resection rate was 94.4% (uESD) vs. 91.7% (cESD). The complication rate was low, with one post-ESD stricture in the uESD group (2.8%) and two post-ESD bleedings in the cESD group (5.6%) (p = 1.000). No postinterventional perforations occurred in either group.

Conclusion

uESD is as effective and safe as cESD. Both techniques achieve high technical and clinical success rates with low complication rates. Future prospective studies should evaluate potential intraoperative advantages of uESD, such as the speed of submucosal entry and possible intraprocedural complications (e.g., bleeding, muscle injury).

Zusammenfassung

Einleitung

Die endoskopische Submukosa-Dissektion (ESD) ist eine etablierte Methode für die Abtragung früher Neoplasien im Gastrointestinaltrakt (GIT). Eine Weiterentwicklung der ESD ist die Resektion unter isotoner Kochsalzlösung (Unterwasser-ESD), auch bekannt als Saline Immersion Therapeutic Endoscopy (SITE). Mögliche Vorteile sind der zügigere Eintritt in die Submukosa sowie die geringere intraprozedurale Komplikationsrate, insbesondere Blutungen in die Submukosa. Ziel dieser Arbeit ist es, erste Daten in Deutschland zur Effektivität und Sicherheit der uESD zu erheben und mit der konventionellen ESD (cESD) zu vergleichen.

Methodik

In einer retrospektiven Analyse wurden die Daten von 72 Patienten, die entweder eine uESD (n=36) oder eine cESD (n=36) erhielten, ausgewertet. Für das Vergleichskollektiv (cESD) wurden Läsionen mit ähnlicher Lokalisation und vergleichbarer Größe eingeschlossen. Die Validierung der Auswahl der Läsionen erfolgte mittels Propensity Score Matching. Behandlungszeit, Komplikationsrate, en-bloc-Resektionsrate, R0-Resektionsrate und Rezidivrate wurden evaluiert.

Ergebnisse

Insgesamt wurden 72 ESD-Prozeduren durchgeführt (36 in der uESD-Gruppe und 36 in der cESD-Gruppe). Davon wurden 11 Eingriffe pro Gruppe im Ösophagus, 3 im Magen, 16 im Kolon und 6 im Rektum durchgeführt. Die mediane Läsionsgröße betrug 40 × 30 mm für uESD und 45 × 30 mm für cESD (p = 0,65). Die mediane Untersuchungszeit war vergleichbar (uESD: 77 Minuten, cESD: 75 Minuten, p = 0.088). Die en-bloc-Resektionsrate lag in beiden Gruppen bei 100%, und die R0-Resektionsrate betrug 94,4% (uESD) vs. 91,7% (cESD). Die Komplikationsrate (Blutung oder Post-ESD Striktur) war niedrig (1× Striktur nach uESD: 2,8%, 2× Nachblutungen nach cESD: 5,6%) (p = 1.00). Postinterventionelle Perforationen wurden nicht beobachtet.

Zusammenfassung

In dieser retrospektiven Analyse konnte gezeigt werden, dass die uESD eine ebenso effektive und sichere Methode ist wie die cESD. Beide Techniken erzielen hohe technische und klinische Erfolgsraten bei niedrigen Komplikationsraten. Weitere prospektive Untersuchungen sollen mögliche intraprozedurale Vorteile der uESD, wie die Geschwindigkeit des Submukosaeintritts sowie intraoperative Komplikationen (z.B. Blutung, Muskelverletzung) evaluieren.

Keywords

Endoscopic Submucosal Dissection - Underwater ESD - Conventional ESD

Schlüsselwörter

Endoskopische Submukosadissektion - Unterwasser ESD - Konventionelle ESD

Publication History

Received: 06 March 2025

Accepted after revision: 11 June 2025

Article published online:
04 August 2025

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