Gastric endoscopic submucosal dissection using sodium carboxymethylcellulose as a new injection substance

Abstract

Aim: To investigate the feasibility of endoscopic submucosal dissection (ESD) using sodium carboxymethylcellulose (SCMC) for gastric cancer.

Methods: During October 2011 through April 2013, 98 lesions from 98 patients who underwent ESD using SCMC (ESD-SCMC) for early gastric cancer were enrolled in this study. Two endoscopists, who had each performed fewer than 30 ESD procedures (less-experienced ESD physicians), performed ESD-SCMC under the supervision of two experts. The primary outcome was the en bloc resection rate. Secondary outcomes included the complete resection rate, the procedural time, the bleeding rate after SCMC injection, and complications. Patient characteristics, time necessary for hemostasis after SCMC injection, rate of treatment completion by less-experienced ESD physicians alone, and the effects of SCMC during ESD and on resected specimens were also evaluated.

Results: The en bloc resection rate was 100%. Among these resections, 87.8% of the cases were completed by a less-experienced ESD physician alone. The complete resection rate was 98.0%. The mean total procedural time was 75.4 min. The mean incidence of intraoperative bleeding following SCMC local injection was 1.7 times. No bleeding was observed after SCMC injection in 29.6% of cases (29/98). Five complications occurred: one case of microperforation (1.0%) and four cases of postoperative bleeding (4.0%). SCMC remained in the submucosa. The submucosa was readily manipulated when the deep submucosa was dissected, even after placing the specimen on a slide.

Conclusion: ESD-SCMC is feasible for the resection of early gastric cancer.

Fig. 1.

ESD-SCMC procedure. a) Marking the outside of the tumor. b) Injecting the mixed sodium hyaluronate and glycerol solution outside the marking and proceeding to the circumferential mucosal incision. c) When the submucosa became sufficiently visible after the circumferential mucosal incision, SCMC was injected into the submucosa. d) During submucosal dissection. The submucosa elevated by SCMC was visible. e) Vessels on the dissected surface after ESD are ablated using hemostatic forceps. SCMC remaining on the dissected surface of the submucosa was removed to the greatest extent possible using hemostatic forceps. The ESD procedure was complete. f) Residual SCMC was visible on the surface on the submucosa side of the resected specimen.

Fig. 2.

Endoscopic views during submucosal dissection after SCMC injection. a) Production of a highly elevated cushion that rendered the submucosal vessels clearly visible. b) Weight of SCMC facilitated traction.

Fig. 3.

Histopathological views of ESD-SCMC cases. a) M cancer case (hematoxylin and eosin stained): The tumor (indicated by the thin arrows) was localized in the mucosa (M). Sufficient residual SCMC (indicated by the thick arrows) was observed in the submucosa (SM). b) SM2 cancer case (hematoxylin and eosin stained): The tumor (indicated by the thin arrows) had infiltrated from the mucosa (M) to the submucosa (SM). However, no problem occurred with evaluation of the depth diagnosis.