Peranal endoscopic myectomy for early rectal cancer with closure using a through-the-scope helical tack and suture system

A 70-year-old man underwent colonoscopy after a positive fecal immunochemical test, revealing a 3-cm rectal tumor located 4 cm above the anal verge ([ Fig. 1a, b ]). Abdominal computed tomography (CT) staged the lesion as cT2N0M0. Endoscopic ultrasound (EUS) suggested deep submucosal invasion with superficial involvement of the muscularis propria ([ Fig. 2a, b ]). Peranal endoscopic myectomy (PAEM) combined with focal endoscopic intermuscular dissection (EID) was performed to achieve en bloc resection. The mucosal defect was subsequently closed using a through-the-scope helical tack and suture system and endoclips ([ Video 1 and ] [ Fig. 3a, b, c ]). Fig. 1 ( a and b ) One 3 cm tumor (JNET type 2B with focal type 3) was found at the rectum, located 4 cm above the anal verge. Fig. 2 ( a ) Abdominal CT demonstrated a rectal lesion with the clinical stage of cT2N0M0 according to the AJCC 8th edition. ( b ) EUS indicated tumor invasion into at least the deep SM layer with superficial involvement of the MP layer. MP, muscularis propria; SM, submucosal. Video 1 Peranal endoscopic myectomy (PAEM) for early rectal cancer with closure using a through-the-scope helical tack and suture system. Download Video Fig. 3 ( a and b ) EID in between the inner (circular) part and the outer (longitudinal) part of the muscularis propria. ( c ) En bloc resection was achieved. The postoperative course was uneventful, with no abdominal pain, hematochezia, or signs of peritonitis. Histopathology confirmed a moderately differentiated pT1 rectal adenocarcinoma with a submucosal invasion of >2 mm. Both horizontal and vertical margins were negative, with a 5 mm clearance ([ Fig. 4a, b, c ]). The patient subsequently received adjuvant concurrent chemoradiotherapy with oral capecitabine and radiotherapy (54 Gy in 30 fractions) in accordance with current guidelines. At 3-month follow-up, CT and colonoscopy demonstrated no evidence of local recurrence or distant metastasis. Fig. 4 Final pathology confirmed rectal adenocarcinoma invading the submucosal layer (pT1), with both horizontal and vertical resection margins measuring 5 mm. ( a ) The upper purple part indicated mucosa, and the lower pink part indicated submucosa to muscularis propria. ( b and c ) The images represented low-power (b 4×) and medium-power (c 10×) magnification. The blue line indicated the lower border of the tumor, while the red line marked the upper margin of the muscular layer. Endoscopic submucosal dissection achieves high R0 resection rates in superficial T1 cancers but is less effective for deep submucosal invasive cancer (D-SMIC).[ 1​ ] While total mesorectal excision remains the standard treatment, it carries significant morbidity. Emerging evidence suggests that PAEM may expand the role of endoscopic therapy to lesions previously considered unsuitable, including selected T2 tumors.[ 2​ ] EID enables dissection within the intermuscular plane, allowing deeper vertical margin clearance while preserving rectal wall integrity and surgical planes. Reported en bloc and R0 resection rates exceed 90% and 80%, respectively, in selected patients.[ 3​ ] [ ​4​ ] In this case, closure with the helical tack and suture system facilitated secure approximation of a large mucosal defect under tension, potentially reducing delayed adverse events such as bleeding or perforation.[ 5​ ] Notably, preoperative CT and EUS overstaged the tumor, likely due to inflammation or fibrosis, underscoring limitations in differentiating T1 from T2 disease. PAEM combined with closure using a through-the-scope helical tack and suture system appears to be a feasible rectum-preserving strategy for selected patients with rectal D-SMIC, although careful selection and long-term outcomes remain essential. Endoscopy_UCTN_Code_TTT_1AO_2AG_3AD Publication History Received: 20 April 2026 Accepted after revision: 02 June 2026 Article published online: 25 June 2026 © 2026. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/). Georg Thieme Verlag KG Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany