The efficacy of endoscopic submucosal dissection for colorectal tumors extending to the dentate line

Safety and Efficacy of Endoscopic Submucosal Dissection for Rectal Neoplasms Extending to the Dentate Line: A Systematic Review and Meta-analysis

OBJECTIVE

Endoscopic submucosal dissection (ESD) is a superior, minimally invasive technique compared with other snare-based endoscopic resection techniques for rectal neoplasms extending to the dentate line (RNDLs). However, performing a successful ESD in the anal canal can be challenging due to vascularity and limited scope stability. In this meta-analysis, we aim to evaluate the safety and efficacy of ESD for RNDLs.

METHODS

We performed a comprehensive electronic database search from January 2005 through January 2024 for studies evaluating outcomes of ESD performed for managing RNDLs. Pooled proportions were calculated using random-effect models. Heterogeneity was evaluated using I2 and Q statistics.

RESULTS

Data were extracted from 11 studies comprising 496 patients. The pooled en bloc resection rates were 93.60% (95% CI = 90.70-95.70). The pooled R0 resection rate was 80.60% (95% CI = 70.50-87.80). The pooled recurrence rate was 4.00% (95% CI = 2.40-6.50). There was no evidence of significant heterogeneity calculated using the Q test and I2 statistic. The main adverse events were anal pain, postprocedural bleeding, and anal stricture with pooled rates of 20.20% (95% CI = 14.80-26.90), 8.20% (95% CI = 4.70-14.0), and 3.50% (95% CI = 2.10-5.70), respectively.

CONCLUSIONS

ESD is a safe and effective option for managing RNDLs with a low recurrence rate. Adverse events such as postprocedural perianal pain, postprocedural bleeding, and anal stenosis seem to be more common compared with colorectal ESD done for more proximal lesions. However, these can typically be managed conservatively or with minimally invasive endoscopic techniques.

Safety and efficacy of ESD for laterally spreading tumors with hemorrhoids close to the dentate line

BACKGROUND

Endoscopic submucosal dissection (ESD) is a curative treatment for laterally spreading tumors (LSTs). However, the outcomes of ESD for LSTs with hemorrhoids remain largely unknown. Our study aimed to evaluate the usefulness of ESD in managing LSTs with hemorrhoids.

MATERIAL AND METHODS

We retrospectively collected 418 consecutive LST patients treated with ESD between 2011 and 2023. A retrospective comparative analysis was conducted.

RESULTS

There were 85 patients included in the hemorrhoids group and 333 patients included in the other group. The en-bloc resection rate, R0 resection rate, and curative resection rate were comparable in these two groups (p > 0.05). The LSTs with hemorrhoids have a significantly higher intraoperative bleeding rate during ESD when compared to the other group (12.9% vs. 5.4%, p = 0.028). Rates of intraoperative perforation and anal pain in the hemorrhoid group were significantly higher than those in the no-hemorrhoid group (2.4% vs. 0%, p = 0.041; 9.4% vs.0.6%, p < 0.001; respectively). Moreover, most of the related manifestations caused by hemorrhoids were relieved to various degrees after ESD.

CONCLUSIONS

ESD is a safe and effective treatment strategy for LSTs with hemorrhoids. A multi-center and prospective study should be conducted in the future to validate our results.

Endoscopic submucosal dissection versus endoscopic mucosal resection for the treatment of rectal lesions involving the dentate line

BACKGROUND

The ideal treatment of epithelial neoplastic rectal lesions involving the dentate line is a controversial issue. Piecemeal endoscopic mucosal resection (EMR) is the most commonly used resection technique, but it is associated with high recurrence rates. Endoscopic submucosal dissection (ESD) has been shown to be safe and effective for the treatment of rectal lesions, but evidence is lacking concerning its application close to the dentate line. The aim of our study is to compare ESD and EMR for the treatment of epithelial rectal lesions involving the dentate line.

METHODS

We identified all cases of endoscopic resections of rectal lesions involving the dentate line performed in two German high-volume centers between 2010 and 2022. Periinterventional and follow-up data were collected and retrospectively analyzed.

RESULTS

We identified 68 ESDs and 62 EMRs meeting our inclusion criteria. ESD showed a significant advantage in en bloc resection rates (89.7% vs. 9.7%; P = 0.001) and complete resection rates (72.1% vs. 9.7%; P = 0.001). The overall curative resection rate was similar between both groups (ESD: 92.6%, EMR: 83.9%; P = 0.324), whereas in the subgroup of low-risk adenocarcinomas ESD was curative in 100% of the cases vs. 14% in the EMR group (P = 0.002). There was one local recurrence after ESD (1,5%) vs. 16 (25.8%) after EMR (P < 0.0001), and the EMR patients required an average of three further interventions.

CONCLUSION

ESD is superior to EMR for the treatment of epithelial rectal lesions involving the dentate line and should be considered the treatment of choice.

Endoscopic Submucosal Dissection Is Safe and Effective for Lesions Located at the Anorectal Junction: Analysis from Two Referral European Centers

Introduction

Endoscopic submucosal dissection (ESD) is a well-established resection technique for colorectal superficial tumors, but its role in the treatment of anorectal junction (ARJ) lesions still remains to be determined. With this study, we aimed to evaluate the feasibility, safety, and efficacy of ESD for the resection of ARJ lesions, in comparison to more proximal rectal lesions.

Methods

We performed a retrospective analysis of prospectively collected data concerning all consecutive rectal ESD procedures performed in two European centers, from 2015 to 2021.

Results

A total of two hundred and fifty-two rectal lesions were included. Sixty (24%) were ARJ lesions, and the remaining 192 (76%) were located proximally. Technical success was achieved in 248 procedures (98%), and its rate was similar in both locations (p = 0.246). Most of the lesions presented high-grade dysplasia/Tis adenocarcinoma (54%); 36 (15%) had submucosal adenocarcinoma, including 20 superficial (sm1) and 16 deeply invasive (>SM1) T1 cancers. We found no differences between ARJ and rectal lesions in regard to en bloc resection rate (100% vs. 96%, p = 0.204), R0 resection rate (76% vs. 75%, p = 0.531), curative resection rate (70% vs. 70%, p = 0.920), procedures' median duration (120 min vs. 90 min, p = 0.072), ESD velocity (14 vs. 12 mm2/min, p = 0.415), histopathology result (p = 0.053), and the need for surgery due to a non-curative ESD (5% vs. 3%, p = 0.739). Also, there was no statistically significant difference that concerns delayed bleeding (7% vs. 8%, p = 0.709), perforation (0% vs. 5%, p = 0.075), or the need for readmission (2% vs. 2%, p = 0.939). Nevertheless, anorectal stenosis (5% vs. 0%, p = 0.003) and anorectal pain (9% vs. 1%, p = 0.002) were significantly more frequent in ARJ lesions.

Conclusion

ESD is a safe and efficient resection technique for the treatment of rectal lesions located in the ARJ.

Difficult colorectal polypectomy: Technical tips and recent advances

Colonoscopy has been shown to be an effective modality to prevent colorectal cancer (CRC) development. CRC reduction is achieved by detecting and removing adenomas, which are precursors of CRC. Most colorectal polyps are small and do not pose a significant challenge for trained and skilled endoscopists. However, up to 15% of polyps are considered "difficult", potentially causing life-threatening complications. A difficult polyp is defined as any polyp that is challenging for the endoscopist to remove owing to its size, shape, or location. Advanced polypectomy techniques and skills are required to resect difficult colorectal polyps. There were various polypectomy techniques for difficult polyps such as endoscopic mucosal resection (EMR), underwater EMR, Tip-in EMR, endoscopic submucosal dissection (ESD), or endoscopic full-thickness resection. The selection of the appropriate modality depends on the morphology and endoscopic diagnosis. Several technologies have been developed to aid endoscopists in performing safe and effective polypectomies, especially complex procedures such as ESD. These advances include video endoscopy system, equipment assisting in advanced polypectomy, and closure devices/techniques for complication management. Endoscopists should know how to use these devices and their availability in practice to enhance polypectomy performance. This review describes several useful strategies and tips for managing difficult colorectal polyps. We also propose the stepwise approach for difficult colorectal polyps.

Efficacy and Safety of Endoscopic Submucosal Dissection for Rectal Tumors Extending Versus Not to the Dentate Line: A Systematic Review and Meta-Analysis

GOALS

To evaluate the outcomes of endoscopic submucosal dissection (ESD) for rectal tumors extending to the dentate line (RTDLs) compared with rectal tumors not extending to the dentate line (non-RTDLs).

BACKGROUND

There is limited composite data on the outcomes of ESD for RTDLs versus non-RTDLs.

STUDY

We performed a systematic review and meta-analysis of studies that reported the clinical outcomes of ESD for RTDLs and non-RTDLs. Main outcomes were pooled estimated rates of en bloc/complete/curative resection, local recurrence, and incidence of bleeding, perforation, stricture, anal pain, and fever.

RESULTS

Six studies were enrolled, including 265 cases of RTDLs and 788 cases of non-RTDLs. The en bloc resection rate was comparable for RTDLs and non-RTDLs [odds ratio (OR), 1.04; 95% confidence interval (CI), 0.55-1.95; P=0.90]. The complete resection rate was significantly lower for RTDLs (OR, 0.59; 95% CI, 0.41-0.83; P=0.003), as well as the curative resection rate (OR, 0.57; 95% CI, 0.38-0.87; P=0.010). The rates of stricture, postoperative anal pain and local recurrence were significantly higher for RTDLs than non-RTDLs (OR, 3.07; 95% CI, 1.01-9.31; P=0.05) (OR, 42.10; 95% CI, 4.73-374.97; P=0.0008) (OR, 3.00; 95% CI, 1.13-7.96; P=0.03), but the higher rates of postoperative bleeding and fever for RTDLs were not significantly (OR, 1.33; 95% CI, 0.53-3.30; P=0.54) (OR, 2.23; 95% CI, 0.55-9.07; P=0.26), as well as its lower perforation rate (OR, 0.85; 95% CI, 0.27-2.63; P=0.78).

CONCLUSIONS

Despite its inferior outcomes than non-RTDLs, ESD is still a feasible and safe treatment for RTDLs if appropriate lesions are treated by experienced operators.

Endoscopic submucosal dissection in tumors extending to the dentate line compared to proximal rectal tumors: a systematic review with meta-analysis

Endoscopic submucosal dissection (ESD) is a validated treatment for early rectal tumors, but whether this therapy is efficient or not for rectal tumors extending to the dentate line (RTDL) remains unclear. We performed a systematic review and meta-analysis to assess the effectiveness and safety of ESD in RTDL compared to non-RTDL. A search in PubMed, Scopus and the Cochrane library up to April 2020 was conducted to identify studies that compared ESD in both localizations (RTDL and non-RTDL), reporting at least one main outcome (en bloc, complete resection, recurrence). Secondary outcomes were adverse event occurrence. Five observational studies including 739 patients with a total of 201 RTDL and 538 non-RTDL were considered. The proportion of female sex (66% vs. 36.9%, P < 0.001) and tumor size [mean difference = 7.75, 95% confidence interval (CI): 3.01-12.49, P = 0.001] were higher in the RTDL group. There were no differences in en bloc resection rates between RTDL and non-RTDL groups [odds ratio (OR): 0.95, 95% CI: 0.50-1.79, P = 0.087]. The complete resection rate was significantly higher in the non-RTDL group (OR: 1.72, 95% CI: 1.18-2.53, P = 0.005, I2 = 0%). However, recurrence rates were comparable (RD: -0.04, 95% CI: -0.07 to 0.00, P = 0.06, I2 = 0%). Concerning adverse events, there were no differences in terms of perforation (OR: 0.9, 95% CI: 0.26-3.08, P = 0.86, I2 = 0%) or delayed bleeding (OR: 0.64, 95% CI: 0.17-2.42, P = 0.51, I2 = 35%). Anal pain rate was 28% (95% CI: 21.4-35.8%). ESD is an effective and safe therapeutic approach for RTDL with comparable recurrence rate to non-RTDL. The lower complete resection rate in RTDL needs to be clarified in studies.

Clinical usefulness of red dichromatic imaging in hemostatic treatment during endoscopic submucosal dissection: First report from a multicenter, open-label, randomized controlled trial

OBJECTIVES

To verify the efficacy and safety of red dichromatic imaging (RDI) in hemostatic procedures during endoscopic submucosal dissection (ESD).

METHODS

This is a multicenter randomized controlled trial of 404 patients who underwent ESD of the esophagus, stomach, colorectum. Patients who received hemostatic treatments by RDI during ESD were defined as the RDI group (n = 204), and those who received hemostatic treatments by white light imaging (WLI) were defined as the WLI group (n = 200). The primary endpoint was a shortening of the hemostasis time. The secondary endpoints were a reduction of the psychological stress experienced by the endoscopist during the hemostatic treatment, a shortened treatment time, and a non-inferior perforation rate, in RDI versus WLI.

RESULTS

The mean hemostasis time in RDI (n = 860) was not significantly shorter than that in WLI (n = 1049) (62.3 ± 108.1 vs. 56.2 ± 74.6 s; P = 0.921). The median hemostasis time was significantly longer in RDI than in WLI (36.0 [18.0-71.0] vs. 28.0 [14.0-66.0] s; P = 0.001) in a sensitivity analysis. The psychological stress was significantly lower in RDI than in WLI (1.71 ± 0.935 vs. 2.03 ± 1.038; P < 0.001). There was no significant difference in the ESD treatment time between RDI (n = 161) and WLI (n = 168) (58.0 [35.0-86.0] vs. 60.0 [38.0-88.5] min; P = 0.855). Four perforations were observed, but none of them took place during the hemostatic treatment.

CONCLUSIONS

Hemostatic treatment using RDI does not shorten the hemostasis time. RDI, however, is safe to use for hemostatic procedures and reduces the psychological stress experienced by endoscopists when they perform hemostatic treatment during ESD. UMIN000025134.

Endoscopic Submucosal Dissection Improves Bloody Stool Associated with Polypoid Type Mucosal Prolapse Syndrome: A Case Series

Mucosal prolapse syndrome (MPS) is a benign inflammatory disease of the rectum that causes bloody stool. Endoscopic treatment for MPS has not been established. We herein report a consecutive case series of endoscopic submucosal dissection (ESD) for MPS. There were four cases treated with ESD alone. All lesions were on the dentate line, and all were polypoid. The median procedure time was 77 minutes. No complications were observed. The median observation period was 1,108 days, and bloody stool and endoscopic recurrence of MPS were not observed.ESD for polypoid-type MPS was an effective treatment for improving bloody stool and suppressing endoscopic recurrence.

Rectal neoplasia extending to the dentate line: clinical outcomes of endoscopic submucosal dissection

BACKGROUND

The European Society of Gastrointestinal Endoscopy (ESGE) and the Japan Gastroenterological Endoscopy Society (JGES) give no specific recommendations on the best treatment for colorectal neoplasia involving the dental line (DLCN).

OBJECTIVE

Aim of this study was to analyse efficacy and safety of Endoscopic Submucosal Dissection in the treatment of colorectal neoplasia involving the dentate line (DLCN) compared to non-DLCN.

DESIGN

Retrospective study.

PATIENTS

We retrospectively evaluated all consecutive patients undergoing ESD for rectal neoplasia at two endoscopical tertiary referral centers (Italy and Japan) from January 2008 to December 2019.

MAIN OUTCOME MEASURES

Anthropometric, clinical, procedural, and follow-up data was collected, analysed, and compared between patients with DLCN and patients with non-DLCN.

RESULTS

Overall, 314 patients were enrolled (163 female, 51.9%). Mean age was 68 years (range, 32-92 years). En-bloc resection was achieved in 311/314 (99%) patients. Lesion size was higher in DLCN group than in the non-DLCN group (46.1 vs 38.9 mm; p = .03). Submucosal invasion rate was also higher in the DLCN group (29.6 vs 18.4%, p = .04). Procedure time was significantly longer in the DLCN group, (89.6 vs. 73.1 min; p = .002). Hospitalization length following ESD was similar in both groups.

LIMITATIONS

Retrospective study design.

CONCLUSIONS

ESD seems to be safe and effective in the treatment of colorectal neoplasia involving the dentate line and can be considered the best therapeutic strategy.

Endoscopic mucosal resection is effective for laterally spreading lesions at the anorectal junction

OBJECTIVE

The optimal approach for removing large laterally spreading lesions at the anorectal junction (ARJ-LSLs) is unknown. Endoscopic mucosal resection (EMR) is a definitive therapy for colorectal LSLs. It is unclear whether it is an effective modality for ARJ-LSLs.

DESIGN

EMR outcomes for ARJ-LSLs (distal margin of ≤20 mm from the dentate line) in comparison with rectal LSLs (distal margin of >20 mm from the dentate line) were evaluated within a multicentre observational cohort of LSLs of ≥20 mm. Technical success was defined as the removal of all polypoid tissue during index EMR. Safety was evaluated by the frequencies of intraprocedural bleeding, delayed bleeding, deep mural injury (DMI) and delayed perforation. Long-term efficacy was evaluated by the absence of recurrence (either endoscopic or histologic) at surveillance colonoscopy (SC).

RESULTS

Between July 2008 and August 2019, 100 ARJ-LSLs and 313 rectal LSLs underwent EMR. ARJ-LSL median size was 40 mm (IQR 35-60 mm). Median follow-up at SC4 was 54 months (IQR 33-83 months). Technical success was 98%. Cancer was present in three (3%). Recurrence occurred in 15.4%, 6.8%, 3.7% and 0% at SC1-SC4, respectively. Among 30 ARJ-LSLs that received margin thermal ablation, no recurrence was identified at SC1 (0.0% vs 25.0%, p=0.002). Technical success, recurrence and adverse events were not different between groups, except for DMI (ARJ-LSLs 0% vs rectal LSLs 4.5%, p=0.027).

CONCLUSION

EMR is an effective technique for ARJ-LSLs and should be considered a first-line resection modality for the majority of these lesions.

Endoscopic submucosal dissection involving the anal canal presents a risk factor for postoperative stricture

BACKGROUND

Although postoperative strictures after endoscopic submucosal dissection (ESD) in the rectum are relatively rare, some rectal lesions require resection involving the anal canal, which is a narrow tract comprising squamous epithelium. To the best of our knowledge, no studies have investigated narrow anal canals when evaluating post-ESD strictures. This study aimed to evaluate the impact of resections involving the anal canal on postoperative stricture development.

METHODS

Between April 2005 and October 2017, 707 rectal lesions were treated with ESD. We retrospectively investigated 102 lesions that required ≥ 75% circumferential resection. Risk factors for post-ESD stricture and, among patients with strictures, obstructive symptoms, and number of dilation therapies required were investigated.

RESULTS

Post-ESD stricture occurred in 18 of 102 patients (17.6%). In the multivariate analysis, circumferential resection ≥ 90% and ESD involving the anal canal (ESD-IAC) were risk factors for postoperative strictures (P ≤ 0.0001 and 0.0115, respectively). Among the patients with strictures, obstructive symptoms were significantly related to anal strictures compared to rectal strictures (100% vs. 27.2%, P = 0.0041). Furthermore, the number of dilation therapies required was significantly greater among patients with anal strictures compared to those with rectal strictures (6.5 times vs. 2.7 times, P = 0.0263).

CONCLUSION

Not only circumferential resection ≥ 90% but also ESD-IAC was a significant risk factor for the stricture after rectal ESD. Furthermore, anal strictures were associated with a significantly higher frequency of obstructive symptoms and larger number of required dilation therapies than were rectal strictures.

Endoscopic submucosal dissection in rectal tumors extending or not to the dentate line: A comparative analysis

BACKGROUND

The feasibility of endoscopic submucosal dissection (ESD) in rectal tumors extending to the dentate line (RTDL) is unclear.

AIMS

To analyze the outcomes of ESD in RTDL compared to non-RTDL, with a special focus on the lower rectum location.

METHODS

Observational multicenter retrospective study. All patients with a rectal tumor who underwent ESD in 2013-2017 were included. A comparative analysis between RTDL and non-RTDL groups was done.

RESULTS

Two-hundred and twenty-eight patients (median age: 69 years, range: 33-89, 51.3% male) with RTDL (n = 65, 28.5%) and non-RTDL lesions (n = 163, 71.5%) were included. There were no significant differences between the en-bloc (89.2% vs. 90.8%, p = 0.718), complete (60% vs. 71.8%, p = 0.084) and curative resection rates (58.5% vs. 68.7%, p = 0.141). The overall complication rate (4.6% vs. 8%, p = 0.370) was not different, independently of the rectal location. Local recurrence was higher in RTDL (7.3% vs. 1.5%, p = 0.065). The indication for surgery due to non-curative resections in the lower rectum was lower in RTDL (9.2% vs. 14.6%, p = 0.378).

CONCLUSION

The safety, effectiveness and long-term impact of ESD in RTDL and non-RTDLs is comparable. Local recurrence in the lower rectum may be higher in RTDL.

A new procedure combining local resection with endoscopic submucosal dissection for low rectal tumor: a four-case series

Rectal tumors are traditionally resected by proctectomy to ensure the achievement of negative margins, an approach associated with an adverse impact on subsequent quality of life due to sequelae such as permanent stoma and urinary and sexual dysfunction. Many studies have now demonstrated that recurrence after local excision of early rectal tumors is significantly higher than would typically be expected. We have developed a new procedure, described herein, that combines local resection with endoscopic submucosal dissection for low rectal tumor. We report four consecutive cases (three submucosal tumors and one tumor with clinical deep submucosal invasion) treated at Hiroshima City Asa Citizens Hospital between January 2009 and March 2018. The mean duration of the procedure was 137 minutes. The en bloc resection and histologically complete resection rates were 100 %. Delayed bleeding and perforation rates were 0 %. Postoperative complications were fever and anal pain (one case each). All patients recovered with conservative therapy. No recurrence was found in any of the four patients during a follow-up period of 56 months. Our combined endoscopic and surgical procedure for low rectal tumors enabled definite negative vertical margins, reduced tumor volume, allowed for accurate pathological diagnosis, preserved rectal function, and aided the decision on additional therapy.

Construction of a preoperative scoring system to predict the difficulty level of colorectal endoscopic submucosal dissection

BACKGROUND

We attempted to examine the factors contributing to the difficulty in performance of colorectal ESD, with the aim of constructing a scoring system that could help in prediction of the difficulty level of the procedure.

METHODS AND MATERIALS

The data were analyzed from two viewpoints: to determine the factors contributing to 1) non-en bloc resection and the factors contributing to 2) a slow resection speed. Factors falling under these two categories contributing to difficulty in performance of ESD were extracted and used to construct a scoring system. The validity of this scoring system was evaluated by calculating the correlation between the score and the resection speed in a different dataset.

RESULTS

Based on the results of our analysis, we assigned scores for various factors as follows: 4 points for EMR of a scarred lesion, 1 point for tumors with a diameter of ≥ 30 mm, 2 points for lesions located in the liver/splenic flexure, 1 point for lesions located in the transverse colon, 3 points for LST-NG-PD/depressed lesions, 1 point for protruded lesions and LST-NG-F lesions (range 0-10). In the validation study, the rank correlation coefficient between the score according to the scoring system and the resection speed was -0.130, representing a weak and negative correlation (P = 0.03). We defined the difficulty level depending on the sum of the scores: 0-2, low difficulty level; 3-5, intermediate difficulty level; ≥ 6, high difficulty level. The average resection speed was 12.6 mm2/min in the group with scores of 0-2, 8.1 mm2/min in the group with scores of 3-5, and 5.5 mm2/min in the group with scores of ≥ 6 (11.2 mm2/min in all lesions).

CONCLUSION

Our colorectal ESD scoring system would be useful for selection of operators with the appropriate skill level in the procedure for colorectal ESD cases.

Combined endoscopic submucosal dissection and transanal minimally invasive surgery for the management of lower rectal adenoma extending above the dentate line: A case report

RATIONALE

Minimally invasive surgery is used to treat early colorectal tumors. Endoscopic submucosal dissection (ESD) for resection of tumors extending above the dentate line (particularly those with concomitant hemorrhoids) is technically difficult. We present a case of a patient with a lower rectal adenoma extending above the dentate line, which underwent combined ESD and transanal minimally invasive surgery (TAMIS) to achieve accurate excision and prevent complications.

PATIENT CONCERNS

A 68-year-old man with a history of blood in stool over 2 to 3 years underwent colonoscopy, which revealed an adenoma measuring 3 cm in size in the lower rectum extending above the dentate line. The part extending above the dentate line was a type Is lesion and that of oral side was a type IIa lesion. Histopathologically, the lesion was diagnosed as a low-grade intramucosal tubulovillous adenoma.

DIAGNOSIS

Intramucosal low-grade adenoma with sessile polyp (type Is).

INTERVENTIONS

The cranial portion of the lesion was dissected via ESD and the anal portion via TAMIS with minimal bleeding. En bloc resection of the tumor was performed.

OUTCOMES

His postoperative period was uneventful, and he was discharged and regularly followed-up.

LESSONS

Combined ESD and TAMIS is effective in patients with benign and early neoplastic lesions of the anorectum extending above the dentate line with concomitant hemorrhoids and can prevent complications.

Clinical outcomes of endoscopic submucosal dissection for laterally spreading tumors involving the dentate line

OBJECTIVE

Endoscopic submucosal dissection (ESD) for laterally spreading tumors (LST) involving the dentate line (LST-DL) is challenging because of the specific anatomical features of the anorectum. This study aimed to evaluate the efficacy and safety of ESD for LST-DL.

METHODS

Consecutive patients with LST-DL who had undergone ESD at our hospital between January 2010 and December 2015 were retrospectively enrolled in this study. Rates of en bloc resection, R0 resection, and complications, pathological characteristics, and tumor recurrence were analyzed and compared with those of LST in the rectum not involving the dentate line (LST-NDL).

RESULTS

Altogether 49 patients with LST-DL (median age 63 years; 39 women; median lesion size 57 mm; median follow-up period of 24 months) and 96 patients with LST-NDL (median age 67 years; 31 women; median lesion size 47 mm; median follow-up period of 31 months) were enrolled. En bloc resection (93.9% [46/49] vs 94.8% [91/96]) and en bloc R0 resection rates (83.7% [41/49] vs 88.5% [85/96]), respectively, for LST-DL and LST-NDL, with no significant differences. However, ESD for LST-DL had a longer procedure time (77 min vs 54 min, P = 0.02), a greater postprocedural perianal pain rate (28.6% vs 0%, P < 0.001), and more anal strictures (4.1% vs 0%, P = 0.04). The complication rates of perforation, bleeding and fever, recurrence rate, and pathological characteristics did not differ between the two groups.

CONCLUSIONS

ESD is a safe and effective therapeutic modality for LST-DL. However, this procedure should be performed by experienced endoscopists and the difficulty needs to be fully considered.

Endoscopic submucosal dissection for rectal neoplasia extending to the dentate line: European experience

Background and study aims  The ideal treatment strategy for rectal neoplasia extending to the dentate line (RNDL) is not well defined. Endoscopic mucosal resection (EMR) and submucosal dissection (ESD) compete with surgical techniques such as transanal endoscopic microsurgery (TEM). Non-Asian data and prospective data on ESD are lacking. The study aim was to evaluate the role of ESD in treatment of RNDL in a Western center. Patients and methods  Eighty-six patients with rectal adenomas were included. ESD was performed in 86 rectal adenomas including 24 RNDLs (27.9 %) and 62 lesions distant from the dentate line (72.1 %). Results  En bloc resection rate was comparable (91.7 % vs. 93.5 %, P  = 0.670) between ESD for RNDL and non-RNDL. R0 resection rate was significantly lower in ESD for RNDL compared to that for non-RNDL (70.8 % vs 88.7 %; P  = 0.039), but most non-R0 resection was unclear margin (Rx) and was not obvious positive margin (R1). Accordingly, the recurrence rate after ESD for RNDL (4.5 %) was not statistically different from that for non-RNDL (0 %, P  = 0.275) and was lower than that previously reported for EMR. Median procedure time was 127 vs. 110 minutes ( P  = 0.182). Risk of delayed bleeding (20.8 % vs. 0 %, P  = 0.001) and postinterventional pain (33.3 % vs. 14.5 %, P  = 0.07) increased in RNDL cases, but they were managed conservatively. Incidence of stricture (4.2 % vs. 1.6 %, P  = 0.483) and perforation (0 % vs. 1.6 %, P  = 1.000) were similar. Conclusions  ESD is a feasible and safe resection technique for RNDLs. A randomized controlled trial comparing ESD to other methods (EMR or transanal surgery) is warranted.

Transanal minimally invasive surgery for local excision of early rectal tumor

INTRODUCTION

Local excision (LE) is used in early rectal cancer and other pathologies for diagnostic purposes and curative treatment, as well as for palliative surgery in patients who are medically unfit for radical resection. Recently, transanal minimally invasive surgery (TAMIS) has been increasingly accepted as a means for performing LE. Here, we present a TAMIS technique for LE to which endoscopic submucosal dissection was applied.

MATERIALS AND SURGICAL TECHNIQUE

We used conventional laparoscopic instruments, including a 10-mm 30° camera. A GelPOINT Path® was introduced into the anal canal to maintain stable pneumorectum and valve-free access. After injecting MucoUp® (SI-4404) into the submucosal layer at the edge of the tumor, we marked dots on the mucosa with cautery using the point of the monopolar diathermy L-hook; we then performed circumferential mucosal incision and submucosal dissection. The remaining defects do not always have to be sutured.

DISCUSSION

TAMIS for LE was performed for seven patients with no postoperative complication and mortality. One lesion required full-thickness resection, one lesion required partial full-thickness resection, and five lesions were dissected completely beneath the submucosal layer. Based on the pathological results, three patients underwent conventional radical resections. One patient had local recurrence at the 8-month follow-up and underwent endoscopic mucosal resection. TAMIS may be a promising option for LE that provides acceptable oncological outcomes and benefits to quality of life.

Colorectal endoscopic submucosal dissection: patient selection and special considerations

Endoscopic submucosal dissection (ESD) enables en bloc resection of large complex colorectal superficial neoplastic lesions, resulting in very low rates of local recurrence, high-quality pathologic specimens for accurate histopathologic diagnosis and potentially curative treatment of early adenocarcinoma without resorting to major surgical resection. The safety and efficacy of the technique, which was pioneered in the upper gastrointestinal tract, has been established by the consistently impressive outcomes from expert centers in Japan and some other eastern countries. However, ESD is challenging to perform in the colorectum and there is a significant risk of complications, particularly in the early stages of the learning curve. Early studies from western centers raised concerns about the high complication rates, and the impressive results from Japanese centers were not replicated. As a result, many western endoscopists are skeptical about the role of ESD and few centers have incorporated the technique into their practice. Nevertheless, although the distribution of expertise, referral centers and modes of practice may differ in Japan and western countries, ESD has an important role and can be safely and effectively incorporated into western practice. Key to achieving this is meticulous lesion assessment and selection, appropriate referral to centers with the necessary expertise and experience and application of the appropriate technique individualized to the patient. This review discusses the advantages, risks and benefits of ESD to treat colorectal lesions and the importance of preprocedure lesion assessment and in vivo diagnosis and outlines a pragmatic rationale for appropriate lesion selection as well as the patient, technical and institutional factors that should be considered.