Factors affecting the effectiveness and safety of submucosal tunneling endoscopic resection for esophageal submucosal tumors originating from the muscularis propria layer.

Background And Aims: Submucosal tunneling endoscopic resection (STER) has been proved to be effective and safe for esophageal submucosal tumors (SMTs) originating from the muscularis propria (MP) layer. This study was aimed to further evaluate the effectiveness, safety, and influencing factors especially the types of mucosal incision of STER in a larger population.

Methods: A total of 89 patients undergoing STER with esophageal SMTs were retrospectively enrolled in this study from May 2012 to November 2016. Clinicopathological, endoscopic, and adverse events (AEs) data were collected and analyzed. Different incision methods were compared to evaluate the optimum incision method.

Results: There were 27 females and 62 males with mean age of 46.5 ± 10.3 years. The medium size of the tumors was 16.0 mm (ranging 10.0-60.0 mm). Inverted T incisions were made in 29 (32.6%) patients, transverse incisions in 12 (13.5%) while longitudinal incisions in 48 (53.9%). En bloc resection was achieved in 70 (78.7%) patients. The residual rate was 1.1% (1/89), and no recurrence was noted even after piecemeal resection. The rate of AEs was 21.3% (19/89), and all of the AEs were cured without intervention or treated conservatively without the need for surgery. The en bloc resection rate was comparable among the three incision groups (P = 0.868); however, the incidence of AEs in the inverted T incision was lower than that in the longitudinal incision (P = 0.003). Fewer clips were used in the inverted T incision group than in the transverse incision group (P = 0.003).

Conclusions: Although STER failed to achieve en bloc resection in 21.3% patients, it was still an effective therapy owing to low residual rate and no recurrence rate after piecemeal resection. STER was safe with no severe AEs; however, minor AEs were common. Inverted T incision seems to be the optimum entry point.