Endoscopic submucosal dissection for anorectal tumor with hemorrhoids close to the dentate line: a multicenter study of Hiroshima GI Endoscopy Study Group

Diagnostic and therapeutic strategies for colorectal tumor with positive muscle-retracting sign

Objectives

Endoscopic submucosal dissection (ESD) for colorectal tumors with positive muscle-retracting (MR) sign often results in incomplete resection or discontinuation owing to the difficulty of submucosal dissection. The present study aimed to evaluate the usefulness of endoscopic ultrasonography (EUS) in diagnosing the MR sign and performing ESD using the pocket-creation method (PCM).

Methods

Thirty-six cases of colorectal tumors with positive MR sign during ESD between January 2015 and December 2021 were retrospectively reviewed. Cases were divided into two groups: 1) the conventional method (CM) group, comprising 29 cases, and 2) the PCM group with seven cases, in which preoperative EUS and ESD using PCM were performed. Treatment outcomes were compared between the groups. The diagnostic yield of EUS for the MR sign was evaluated among large sessile tumors >20 mm in which preoperative EUS was performed.

Results

Histologic diagnosis was adenoma or Tis carcinoma in 12 cases (33%), T1 carcinoma in 18 cases (50%), T2 carcinoma in four cases (11%), and unevaluable in two cases (6%). The sensitivity and specificity of the EUS-MR sign for large sessile tumors were 87.5% and 83.3%, respectively. ESD was achieved in all cases in the PCM group, although it was discontinued in eight cases (28%) in the CM group. There were significant differences between the PCM and CM groups in en bloc resection (100% vs. 48%, p = 0.013) and R0 resection rates (71% vs. 31%, p = 0.049).

Conclusion

The MR sign can be predicted by preoperative EUS, and ESD using PCM allows en bloc resection.

Endoscopic intermuscular dissection (EID) for removing early rectal cancers and benign fibrotic rectal lesions

In the current era of screening colonoscopy and increasing incidence of early rectal cancer, interventional endoscopy moves toward resections in deeper planes than the submucosal layer. Several reports support the use of endoscopic intermuscular dissection (EID) instead of endoscopic submucosal dissection (ESD) for the removal of deeply invasive rectal submucosal cancers. The resection plane into the intermuscular space, the space between the longitudinal (external) and circular (internal) muscle layer, allows radical removal of rectal invasive submucosal cancers. Furthermore, the technique offers the potential for dissection of scarred and severe fibrotic lesions in the rectum by cutting deeper and performing a partial myectomy avoiding the narrow submucosal space. We present 23 cases of EIDs both for deeply invasive rectal cancers and benign rectal lesions. This is the first report in the literature of EID resections for malignant and benign disease, including cases of severely fibrotic rectal lesions.

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.

Dentate line invasion as a predictive factor of poor distant relapse-free survival in locally advanced lower rectal cancer with anal sphincter involvement

Background

While an important surgical landmark of the dentate line has been established for locally advanced lower rectal cancer (LALRC), the prognostic significance of dentate line invasion (DLI) has not been well defined. This study aimed to explore the impact of DLI on prognosis in LALRC patients with anal sphincter involvement after neoadjuvant chemoradiotherapy followed by surgery.

Methods

We analyzed 210 LALRC patients and classified them into DLI group (n = 45) or non-DLI group (n = 165). The exact role of DLI in survival and failure patterns was assessed before and after propensity-score matching(PSM). Finally, 50 patients were matched.

Results

Before matching, patients in the DLI group had poorer 5-year distant relapse-free survival (DRFS) (P < 0.001), disease-free survival (DFS) (P < 0.001), and overall survival (OS) (P = 0.022) than those in the non-DLI group, with the exception of local recurrence-free survival (LRFS) (P = 0.114). After PSM, the 5-year DRFS, DFS, OS, and LRFS were 51.7% vs. 79.8%(P = 0.026), 51.7% vs. 79.8%(P = 0.029), 71.6% vs. 85.4%(P = 0.126), and 85.7% vs. 92.0%(P = 0.253), respectively, between the two groups. DLI was also an independent prognostic factor for poor DRFS with (Hazard ratio [HR] 3.843, P = 0.020) or without matching (HR 2.567, P = 0.001). The DLI group exhibited a higher rate of distant metastasis before (44.4% vs. 19.4%, P < 0.001) and after matching (48.0% vs. 20.0%, P = 0.037) and similar rates of locoregional recurrence before (13.3% vs.7.9%, P = 0.729) and after matching (16.0% vs.12.0%, P = 1.000).

Conclusions

DLI may portend worse DRFS and distant metastasis in LALRC patients with anal sphincter involvement, and this may be an important variable to guide clinicians.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10299-8.

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.

Efficacy of single-balloon overtube for endoscopic submucosal dissection in the proximal colon: A propensity score-matched analysis

OBJECTIVES

A single-balloon overtube (SBO) can improve poor scope operability during colonic endoscopic submucosal dissection (ESD). We aimed to evaluate the clinical usefulness of SBO for ESD in the proximal colon and the predictive factors for cases in which SBO is useful.

METHODS

A total of 88 tumors located in the proximal colon resected by balloon-assisted ESD (BA-ESD) using SBO and 461 tumors resected by conventional ESD (C-ESD) between June 2015 and November 2020 were considered. Seventy-eight tumors each in the BA-ESD and C-ESD groups were matched by propensity score matching. ESD outcomes were compared between the groups, and a decision tree analysis was performed to explore the predictive factors for cases in which SBO is useful.

RESULTS

There were no significant differences between the groups in the major outcomes such as en bloc resection rate (95% vs. 99%, p = 0.17), R0 resection rate (92% vs. 96%, p = 0.30), mean dissection speed (16 mm²/min vs. 16 mm²/min, p = 0.53), and intraoperative perforation rate (5% vs. 6%, p = 0.73). Even when considering cases with poor preoperative scope operability, there were no significant differences between the groups. Comparison of tumors ≥40 mm in diameter between the groups confirmed that the intraoperative perforation rate was significantly lower in the BA-ESD group than in the C-ESD group (0% vs. 24%, p = 0.0188).

CONCLUSION

SBO is useful for ESD of tumors ≥40 mm in diameter in the proximal colon to prevent intraoperative perforation, which usually has a long procedure time.

Indications and outcomes of colorectal hybrid endoscopic submucosal dissection: a large multicenter 10-year study

BACKGROUND AND AIMS

Hybrid endoscopic submucosal dissection (ESD) is a colorectal lesion resection procedure that includes both planned and salvage procedures. Previous colorectal hybrid ESD studies have involved single institutions or few operators over a short timeframe, and the size for indication has not been established. In this multicentre study, we investigated the clinical outcomes of hybrid ESD for colorectal tumors that met the 30 mm lesion size criterion.

METHODS

From January 2008 to December 2018, colorectal hybrid ESD was performed for 172 lesions (diameter range, ≥ 20- < 30 mm) at Hiroshima GI Endoscopy Research Group. We compared clinicopathological characteristics and outcomes between 56 and 116 lesions in planned and salvage groups, respectively. We also compared data between 2008 and 2013 (the first period) and 2014 and 2018 (the second period) to assess operator experience.

RESULTS

No significant difference was found in the complete en bloc resection rate between the planned and salvage groups (92.9% vs. 83.6%, respectively). Procedure time was shorter in the planned group (44.5 min) than in the salvage group (72.0 min, p < 0.01). The perforation rate was higher in the salvage group (21.6%) than in the planned group (0%, p < 0.01); however, the perforation rate during snaring in the salvage group was 1.8%. During the second period relative to the first period, we recorded a significantly higher complete en bloc resection rate (95.7% vs. 75.6%, respectively, p < 0.01) and experienced operator rate (75.5% vs. 53.9%, respectively, p < 0.01). Furthermore, no significant difference was found in the complete en bloc resection rate between the planned and salvage groups during the second period (100% vs. 94.4%, respectively).

CONCLUSION

Colorectal hybrid ESD, especially salvage hybrid ESD performed by experienced operators, is adoptable and safe for lesions with diameters ranging from ≥ 20 to < 30 mm.

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.

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.

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.

Colorectal endoscopic submucosal dissection in special locations

Colorectal endoscopic submucosal dissection (ESD) is considered one of the most challenging endoscopic procedures for novice endoscopists. When compared with the stomach, the colon and rectum have a narrower tubular lumen, greater angulation at the flexures, and a thinner muscle layer. These factors make endoscopic control and maneuverability difficult. ESD of the colorectum was considered more difficult than gastric and esophageal ESD. However, with learning from the experts, practicing, and selecting an appropriate technique, most of colorectal ESD could be performed successfully. Nevertheless, some colorectal locations are extremely specialized either from unique anatomy or given unstable scope position. Accordingly, the objective of this review was to provide endoscopists with an overview of the techniques and outcomes associated with ESD at these special colorectal locations. ESD at the discussed special locations of the ileo-colo-rectum was found to be feasible, and outcomes were comparable to those of ESD performed in non-special locations of the ileo-colo-rectum. Practice for skill improvement and awareness of the unique characteristics of each special location is the key to performing successful ESD.

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.

The utility of a novel colonoscope with retroflexion for colorectal endoscopic submucosal dissection

Background and study aims  The PCF-H290TI/L produced by Olympus is a novel colonoscope equipped with some advantageous features for endoscopic treatment. It is expected to improve the potential for retroflexion and overall endoscope operability, which can reduce the difficulty of performing colorectal ESD. The aim of this study was to evaluate the utility of the novel colonoscope in colorectal ESD. Methods  Three hundred and forty-eight consecutive colorectal lesions resected via ESD between June 2014 and January 2017 at Hiroshima University Hospital were included in the retroflexion ability analysis. We compared the retroflexion potential of PCF-H290TI to that of a conventional endoscope. Two hundred and twenty-seven colorectal lesions located in the left-sided colon and resected with ESD between April 2009 and February 2018 were enrolled in the treatment outcome analysis. Treatment outcomes using PCF-H290TI compared to those of the conventional colonoscope, and outcomes of the PCF-H290TI with retroflexion compared to those of the conventional colonoscope without retroflexion were evaluated by propensity score matching. Results  The retroflexion rate with the PCF-H290TI was 76 %, which was significantly higher than the 44 % rate with the conventional scope. Endoscope operability was better and dissection speed was faster when using the PCF-H290TI with retroflexion compared to the conventional colonoscope without retroflexion. There were no significant differences between the groups in en bloc resection rate and adverse events. Conclusion  Compared to the conventional colonoscope, the PCF-H290TI/L made it easier to perform ESD via a retrograde approach regardless of tumor location, and thus may be useful for performing colorectal ESD.

Dual Red Imaging Maintains Clear Visibility During Colorectal Endoscopic Submucosal Dissection

BACKGROUND

The endoscopic lens becomes clouded and its visibility reduces during colorectal endoscopic submucosal dissection (ESD), especially in cases with submucosal fatty tissue. Dual red imaging (DRI) is a novel image-enhanced endoscopic technique that improves endoscopic visibility.

AIMS

This study aimed to evaluate the predictive factors of submucosal fatty tissue and the clinical usefulness of DRI in maintaining clear visibility during colorectal ESD.

METHODS

The study participants included 586 consecutive patients with 645 colorectal tumors who underwent ESD between January 2014 and July 2017. First, the degree of submucosal fatty tissue was evaluated by reviewing recorded images, and the clinical characteristics of the patients and tumors related to severe submucosal fatty tissue were evaluated. Second, 34 tumors resected using DRI were propensity score-matched in a 1:1 ratio to other resected tumors using white light imaging (WLI), and the degree of endoscope lens cloudiness and clinical outcomes were evaluated.

RESULTS

The proportion of tumors located in the right side of the colon, body mass index (≥ 25, BMI), and hemoglobin A1c (≥ 6.5%, HbA1c) were significantly higher in patients with severe submucosal fatty tissue. The visibility in the DRI group was significantly better than in the WLI group. Treatment outcomes in the DRI group were as good as those in the WLI group.

CONCLUSIONS

Tumor location in the right side of the colon, BMI (≥ 25), and HbA1c (≥ 6.5%) are the predictive factors of severe submucosal fatty tissue. DRI is useful in maintaining clear visibility during colorectal ESD, especially with submucosal fatty tissue.

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.

Short-term outcomes of endoscopic submucosal dissection for superficial cecal tumors: a comparison between extension and nonextension into the appendiceal orifice

BACKGROUND

Few studies have investigated the use of endoscopic submucosal dissection (ESD) for cecal tumors extending into the appendiceal orifice. Herein, we assessed the feasibility and safety of ESD for cecal tumors extending into the appendiceal orifice.

METHODS

We retrospectively examined the outcomes of ESD for 78 patients with 78 cecal tumors (male/female ratio, 40/38; mean [standard deviation, SD] age, 67 [9] years; mean [SD] tumor size, 32 [15] mm), who underwent ESD at the Hiroshima University Hospital between October 2008 and March 2016. The indication for ESD in cecal tumors extending into the appendiceal orifice was recognition of the distal edge of the lesion in the appendix. They were classified into two groups: patients with cecal tumors extending (Group A: 29 patients, 29 tumors) and not extending (Group B: 49 patients, 49 tumors) into the appendiceal orifice. We compared the outcomes of ESD between both groups.

RESULTS

No significant differences in clinicopathological characteristics were observed between both groups. The rate of severe submucosal fibrosis in Group A (48%) was significantly higher than that in Group B (24%) (p < 0.05). The mean (SD) procedure speed in Group A (14 [10] mm²/min) was significantly slower than that in Group B (23 [16] mm²/min) (p < 0.01). The en bloc resection rates in Groups A and B were 90% and 96%, respectively. There were no significant differences in adverse events reported between both groups.

CONCLUSIONS

ESD for cecal tumors with extension into the appendiceal orifice is effective and safe.

Clinical outcomes of endoscopic submucosal dissection for colorectal tumors: a large multicenter retrospective study from the Hiroshima GI Endoscopy Research Group

BACKGROUND AND AIMS

Although advanced high-volume centers have reported good outcomes of colorectal endoscopic submucosal dissection (ESD), a limited number of highly skilled experts in specialized institutions performed these procedures. We undertook a retrospective multicenter survey, which included nonspecialized hospitals, to investigate the clinical outcomes of colorectal ESD.

METHODS

We recruited 1233 consecutive patients with 1259 colorectal tumors resected by ESD at 12 institutions. We evaluated the en bloc resection rate, histologic complete resection rate, curative (R0) resection rate, adverse events, and the long-term prognoses, including local recurrence, metachronous tumor development, and survival rate.

RESULTS

The en bloc, histologic complete, and R0 resection rates were 92.6%, 87.4%, and 83.7%, respectively. The delayed bleeding, intraoperative perforation, and delayed perforation rates were 3.7%, 3.4%, and .4%, respectively. The long-term outcomes analysis included 1091 patients (88.4%). Local recurrences occurred in 1.7%, and metachronous tumors (>5 mm) developed in 11.0% of the patients. The 3- and 5-year overall survival rates were 95.1% and 92.3%, respectively. The number of colonic tumors, severe submucosal fibrosis, and en bloc resection rates were significantly higher in the high-volume centers (Group H) than those in the low-volume centers (Group L). The average tumor size in Group H was significantly larger than that in Group L.

CONCLUSIONS

Colorectal ESDs are feasible, have acceptable adverse event risks, and favorable long-term prognoses. (Clinical trial registration number: UMIN000016197.).

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.

Case of pediatric traditional serrated adenoma resected via endoscopic submucosal dissection

Traditional serrated adenoma (TSA) is a type of serrated polyp of the colorectum and is thought to be a precancerous lesion. There are three types of serrated polyps, namely, hyperplastic polyps, sessile serrated adenomas/polyps, and TSAs. TSA is the least common of the three types and accounts for about 5% of serrated polyps. Here we report a pediatric case of TSA that was successfully resected by endoscopic submucosal dissection (ESD). This rare case report describes a pediatric patient with no family history of colonic polyp who was admitted to our hospital with hematochezia. On colonoscopy, we found a polypoid lesion measuring 10 mm in diameter in the lower rectum. We selected ESD as a surgical option for en bloc resection, and histopathological examination revealed TSA. The findings in this case suggest that TSA with precancerous potential can occur in children, and that ESD is useful for treating this lesion.

Long-term outcomes after endoscopic submucosal dissection for superficial colorectal tumors

BACKGROUND AND AIMS

Endoscopic submucosal dissection (ESD) is an effective procedure for en bloc resection of superficial colorectal tumors regardless of tumor size or location. However, there are few reports on long-term outcomes for patients with superficial colorectal tumors after ESD. We therefore aimed to evaluate the long-term outcomes after ESD for superficial colorectal tumors.

METHODS

ESD was performed on 257 colorectal tumors in 255 consecutive patients at Hiroshima University Hospital between June 2003 and July 2010. We investigated the following variables: patient characteristics, the American Society of Anesthesiologists score, tumor location, tumor size, growth type, histology, en bloc resection rate, achievement of curative resection, procedure time, and adverse events. The 5-year overall survival (OS), 5-year disease-specific survival (DSS), local recurrence, and metachronous tumor occurrence were also analyzed.

RESULTS

We identified 224 tumors in 222 patients who were confirmed dead or had follow-up data for more than 5 years. After a median follow-up of 79 months, 5-year OS and DSS rates were 94.6% and 100%, respectively. The local recurrence rate (1.5%) was significantly higher in patients undergoing piecemeal resection (9.1%) compared with en bloc resection (0.6%), in cases of histologic incomplete resection compared with complete resection, and in cases of non-R0 resection compared with R0 resection. The rates of total number of tumors (≥6 mm) and carcinoma metachronous tumors after ESD without additional surgical resection were 18.9% (38/201) and 4.0% (8/201), respectively.

CONCLUSIONS

Long-term outcomes after ESD for superficial colorectal tumors are favorable. Patients should be surveyed for both local recurrence and metachronous tumors after ESD.

First reported case of per anal endoscopic myectomy (PAEM): A novel endoscopic technique for resection of lesions with severe fibrosis in the rectum

Background and study aims A 54-year-old man was diagnosed with a rectal tumor extending through the submucosal layer. The patient refused surgery and therefore endoscopic submucosal dissection (ESD) was pursued. The lesion exhibited the muscle retraction sign. After dissecting circumferentially around the fibrotic area by double tunneling method, a myotomy was performed through the internal circular muscle layer, creating a plane of dissection between the internal circular muscle layer and the external longitudinal muscle layer, and a myectomy was completed. The pathologic specimen verified T1b grade 1 sprouting adenocarcinoma with 4350 µm invasion into the submucosa with negative resection margins.