Endoscopic Resection for Small Rectal Neuroendocrine Tumors

Experimental: mEMR-C group

In mEMR-C group, enrolled patients will receive modified EMR-C without submucosal injection.

Verfahren: mEMR-C procedure

A transparent cap with an inner groove (MH-593; Olympus, Tokyo, Japan) was attached to the forward-viewing colonoscope. After the endoscope was inserted into the rectum, a crescent-shaped electrosurgical snare was passed through the sheath and looped along the inner groove of the cap. Submucosal injections were not required in this method. The tumor was suctioned into the cap and grasped by tightening the snare. After confirming the appropriate snare placement, both the tumor and overlying mucosa were resected using electric cautery (Endocut Q, effect 2, VIO 200D; ERBE, Tübingen, Germany), and the resected tumor was sent for pathological examination. Endoscopic examination was repeated without a transparent cap to evaluate the wound carefully in cases of perforation or bleeding and to ensure the absence of residual tumor tissues. If there was spurting or active bleeding, hot forceps were used to stop the bleeding.

Aktiver Komparator: ESD group

In ESD group, enrolled patients will receive the standard treatment modality of ESD to remove the rectal NET

Verfahren: ESD procedure

ESD was performed as the standard procedure and has been widely described and used. First, dots were marked approximately 5 mm from the periphery of the lesion using coagulation. Subsequently, a diluted sodium hyaluronate solution with indigo carmine dye was injected submucosally. Mucosal incision and submucosal dissection were performed using a T-Type ESD Knife (Micro-Tech, Nanjing, China) or Dual-knife (Olympus Medical, Tokyo, Japan). After resection was completed, all visible vessels on the artificial wound were thoroughly coagulated to prevent postoperative bleeding.

histological complete resection

complete single-piece (en bloc) resection of the targeted lesion with horizontal and vertical free margins.

Dauer des Aufenthalts

berechnet vom Tag der Aufnahme bis zum Tag der Entlassung

Krankenhauskosten

stellen die Kosten des Krankenhauses für einen Krankenhausaufenthalt dar

success rate of operation

the proportion of patients whose tumors were successfully resected in each group

en bloc resection

complete single resection of the targeted lesion, irrespective of whether the basal and lateral tumor margins were infiltrated or undetermined

operation time

the time required to complete the procedure, was taken from the installation of the snare in the mEMR-C or the first submucosal injection in ESD to the end of complete resection of the targeted area or a failure or complication of the procedure which required discontinuation

complications

perforation or hemorrhage during or after operation.

operation cost

the cost of mEMR-C or ESD procedures, except the cost of other endoscopic procedures

histopathologic grade

NET grade 1, NET grade 2, NET grade 3, and NEC