Comparison of endoscopic submucosal dissection and transanal endoscopic microsurgery for T1 rectal neuroendocrine tumors: a propensity score-matched study

Current status of endoscopic resection for small rectal neuroendocrine tumors

Rectal neuroendocrine tumor (rNET) is an indolent malignancy often detected during colonoscopy screening. The incidence of rNET has increased approximately 10-fold over the past 30 years. Most rNETs detected during screening endoscopy are small, measuring < 10 mm. Current guidelines recommend endoscopic resection for small, well-differentiated rNET using modified endoscopic submucosal resection (mEMR) or endoscopic submucosal dissection. However, the optimal endoscopic treatment method remains uncertain. This paper summarizes the evidence on mEMR with submucosal stretching, mEMR without submucosal stretching, endoscopic submucosal dissection and endoscopic full-thickness resection. Given that rNETs often exhibit submucosal invasion, achieving adequate resection depth is crucial to ensure histological complete resection. mEMR with submucosal stretching appears favorable due to its high rate of histological complete resection, safety and convenience. Risk factors associated with lymph node and distant metastases are also discussed. A treatment algorithm is proposed to facilitate clinical decision-making.

Comparison of endoscopic submucosal dissection and transanal endoscopic surgery for the treatment of rectal neoplasia: A systematic review and meta-analysis

BACKGROUND AND AIM

Minimally invasive techniques offer alternatives to conventional surgery in the treatment of early-stage colorectal cancer, reducing morbidity. Transanal Endoscopic Microsurgery (TEM) and Transanal Minimally Invasive Surgery (TAMIS) are widely used, while Endoscopic Submucosal Dissection (ESD) is gaining attention for its ability to achieve complete resection with low recurrence rates. This study compares the efficacy and safety of ESD with Transanal Endoscopic Surgery (TES).

METHODS

The authors performed a systematic review and meta-analysis of comparative studies involving patients with endoscopically resectable rectal lesions. Electronic searches were conducted in MEDLINE, EMBASE, Cochrane, and LILACS. Outcomes included recurrence rate, complete resection, en bloc resection, hospital stay, procedure time, and complication rate.

RESULTS

The analysis included ten observational studies and one Randomized Controlled Trial (RCT) involving 1,094 patients. No significant differences were found in terms of recurrence rate, en bloc resection, R0 resection, and complications between techniques. The RCT showed a shorter procedure time in the TES (RD = 16.6; 95 % CI 8.88 to 24.32; p < 0.0001), whereas observational studies found no significant difference. In addition, observational studies found a shorter hospital stay duration in the ESD (MD = -1.22; 95 % CI -2.11 to -0.33; I2 = 82 %; p < 0.007), while the RCT found no difference.

CONCLUSION

ESD and TES are safe and effective for the treatment of early-stage rectal tumors. Rates of local recurrence, block resection, R0 resection, complications, and procedure time were similar. However, the RCT showed a shorter procedure time with TES, while observational studies showed a shorter hospital stay with ESD.

Comparison of endoscopic submucosal dissection and transanal endoscopic microsurgery for stage 1 rectal neuroendocrine tumors

BACKGROUND

Stage 1 rectal neuroendocrine tumors (NETs) are best treated with endoscopic submucosal dissection (ESD) or transanal endoscopic microsurgery (TEM) for local resection.

AIM

To investigate the safety and efficacy of ESD and TEM for local resection of stage 1 rectal NETs.

METHODS

This retrospective observational analysis included patients with clinical stage 1 rectal NETs (cT1N0M0, less than 20 mm) who underwent ESD or TEM. The ESD and TEM groups were matched to ensure that they had comparable lesion sizes, lesion locations, and pathological grades. We assessed the differences between groups in terms of en bloc resection rate, R0 resection rate, adverse event rate, recurrence rate, and hospital stay and cost.

RESULTS

Totally, 128 Lesions (ESD = 84; TEM = 44) were included, with 58 Lesions within the matched groups (ESD = 29; TEM = 29). Both the ESD and TEM groups had identical en bloc resection (100.0% vs 100.0%, P = 1.000), R0 resection (82.8% vs 96.6%, P = 0.194), adverse event (0.0% vs 6.9%, P = 0.491), and recurrence (0.0% vs 3.4%, P = 1.000) rates. Nevertheless, the median hospital stay [ESD: 5.5 (4.5-6.0) vs TEM: 10.0 (7.0-12.0) days; P < 0.001], and cost [ESD: 11.6 (9.8-12.6) vs TEM: 20.9 (17.0-25.1) kilo-China Yuan, P < 0.001] were remarkably shorter and less for ESD.

CONCLUSION

Both ESD and TEM were well-tolerated and yielded favorable outcomes for the local removal of clinical stage 1 rectal NETs. ESD exhibits shorter hospital stay and fewer costs than TEM.

Endoscopic submucosal dissection for rectal neuroendocrine tumours: A multicentric retrospective study

INTRODUCTION

Endoscopic Submucosal Dissection (ESD) has been reported as a feasible and effective treatment for Rectal Neuroendocrine Tumours (R-NETs). However, most of the experience on the topic comes from retrospective tertiary centre from Eastern Asia. Data on ESD for R-NETs in Western centres are lacking.

MATERIALS AND METHODS

This is a retrospective study, including patients who underwent endoscopic resection of R-NETS by ESD between 2015 and 2020 in Western Centres. Important clinical variables such as demographic, size of R-NETs, histological type, presence of lymphovascular invasion or distant metastasis, completeness of the endoscopic resection, recurrence, and procedure related complications were recorded.

RESULTS

40 ESD procedure on R-NETs from 39 patients from 8 centres were included. Mean R-NETs size was 10.3 mm (SD 4.01). Endoscopic en-bloc resection was achieved in 39/40 ESD (97.5 %), R0 margin resection was obtained in 87.5 % (35/40) of the procedures, one patient was referred to surgery for lymphovascular invasion, two procedures (5 %) reported significant episodes of bleeding, whereas a perforation occurred in one case (1/40, 2.5 %) managed endoscopically. Recurrence occurred in 1 patient (2.5 %).

CONCLUSION

ESD is an effective and safe treatment for R-NETs in western centres.

Endoscopic Management of Gastro-Entero-Pancreatic Neuroendocrine Tumours: An Overview of Proposed Resection and Ablation Techniques

A literature search of MEDLINE/PUBMED was conducted with the aim to highlight current endoscopic management of localised gastro-entero-pancreatic NETs. Relevant articles were identified through a manual search, and reference lists were reviewed for additional articles. The results of the research have been displayed in a narrative fashion to illustrate the actual state-of-the-art of endoscopic techniques in the treatment of NETs. Localised NETs of the stomach, duodenum and rectum can benefit from advanced endoscopic resection techniques (e.g., modified endoscopic mucosal resection, endoscopic full thickness resection, endoscopic submucosal dissection) according to centre expertise. Radiofrequency thermal ablation can be proposed as an alternative to surgery in selected patients with localised pancreatic NETs.

Endoscopic submucosal dissection vs transanal endoscopic surgery for rectal tumors: A systematic review and meta-analysis

BACKGROUND

Endoscopic submucosal dissection (ESD) and transanal endoscopic submucosal dissection (TES) are widely employed surgical techniques. However, the comparative efficacy and safety of both remain inconclusive.

AIM

To comprehensively analyze and discern differences in surgical outcomes between ESD and TES.

METHODS

We conducted a systematic search of the electronic databases PubMed, Embase, Cochrane Central Register of Controlled Trials, Scopus, and CINAHL from inception till August 2023. We analyzed outcomes including recurrence rate, en bloc resection, R0 resection rate, perforation rate, procedure length, and hospital stay length applying a random-effects inverse-variance model. We assessed publication bias by conducting an Egger's regression test and sensitivity analyses.

RESULTS

We pooled data from 11 studies involving 1013 participants. We found similar recurrence rates, with a pooled odds ratio of 0.545 (95%CI: 0.176-1.687). En bloc resection, R0 resection, and perforation rate values were also similar for both ESD and TES. The pooled analysis for procedure length indicated a mean difference of -4.19 min (95%CI: -22.73 to 14.35), and the hospital stay was on average shorter for ESDs by about 0.789 days (95%CI: -1.671 to 0.093).

CONCLUSION

Both ESD and TES displayed similar efficacy and safety profiles across multiple outcomes. Our findings show that individualized patient and surgeon preferences, alongside specific clinical contexts, can be considered when selecting between these two techniques.

Comparison between Endoscopic Submucosal Dissection and Transanal Endoscopic Microsurgery in Early Rectal Neuroendocrine Tumor Patients: A Meta-Analysis

PURPOSE

To compare the effectiveness, safety and cost-effectiveness of endoscopic submucosal dissection (ESD) with transanal endoscopic microsurgery (TEM) in early rectal neuroendocrine tumor (RNET) patients. This article will provide reliable evidence for surgeons in regards to clinical decision-making.

METHODS

Systematic literature retrieval was performed in Pubmed, Embase and Cochrane database from 2013/4/30 to 2023/4/30. Methodology validation was performed by using the Newcastle-Ottawa Scale (NOS). Data-analysis was conducted by using the Review manager version 5.3 software.

RESULTS

A total of three retrospective studies were included in our meta-analysis. All eligible studies were considered to be high quality. By comparing baseline characteristics between TEM and ESD, patients in the TEM group seemed to be characterized by a larger tumor size and lower tumor level, even though no statistical significance was found. Clear statistical significance favoring TEM was identified in terms of R0 resection rate, procedure time and hospital stay. No statistical significance was found in terms of recurrence rate, adverse events rate and additional treatment rate.

CONCLUSIONS

Compared with ESD, TEM was a more effective treatment modality for early RNET patients; it was associated with a relatively higher R0 resection rate and a similar degree of safety. However, the relatively higher cost and complicated manipulation restricted the promotion of TEM. Surgeons should opt for TEM as a primary treatment in patients with a larger tumor size and deeper degree of tumorous infiltration if the financial condition and hospital facility permit.

Role of Advanced Gastrointestinal Endoscopy in the Comprehensive Management of Neuroendocrine Neoplasms

Neuroendocrine neoplasms (NENs), also called neuroendocrine tumors (NETs), are relatively uncommon, heterogenous tumors primarily originating in the gastrointestinal tract. With the improvement in technology and increasing use of cross-sectional imaging and endoscopy, they are being discovered with increasing frequency. Although traditionally considered indolent tumors with good prognoses, some NENs exhibit aggressive behavior. Timely diagnosis, risk stratification, and management can often be a challenge. In general, small NENs without local invasion or lymphovascular involvement can often be managed using minimally invasive advanced endoscopic techniques, while larger lesions and those with evidence of lymphovascular invasion require surgery, systemic therapy, or a combination thereof. Ideal management requires a comprehensive and accurate understanding of the stage and grade of the tumor. With the recent advancements, a therapeutic advanced endoscopist can play a pivotal role in diagnosing, staging, and managing this rare condition. High-definition white light imaging and digital image enhancing technologies like narrow band imaging (NBI) in the newer endoscopes have improved the diagnostic accuracy of traditional endoscopy. The refinement of endoscopic ultrasound (EUS) over the past decade has revolutionized the role of endoscopy in diagnosing and managing various pathologies, including NENs. In addition to EUS-directed diagnostic biopsies, it also offers the ability to precisely assess the depth of invasion and lymphovascular involvement and thus stage NENs accurately. EUS-directed locoregional ablative therapies are increasingly recognized as highly effective, minimally invasive treatment modalities for NENs, particularly pancreatic NENs. Advanced endoscopic resection techniques like endoscopic submucosal dissection (ESD), endoscopic submucosal resection (EMR), and endoscopic full-thickness resection (EFTR) have been increasingly used over the past decade with excellent results in achieving curative resection of various early-stage gastrointestinal luminal lesions including NENs. In this article, we aim to delineate NENs of the different segments of the gastrointestinal (GI) tract (esophagus, gastric, pancreatic, and small and large intestine) and their management with emphasis on the endoscopic management of these tumors.

Clinicopathological characteristics of rectal multiple neuroendocrine neoplasms and literature review

BACKGROUND

There are only a few epidemiological reports available for reference. The clinicopathological features are not clear, so there is no consensus on treating rectal multiple neuroendocrine neoplasms. This study aims to summarize the clinicopathological characteristics and preliminarily discuss the clinical diagnosis and treatment of rectal multiple neuroendocrine neoplasms.

METHODS

This study retrospectively analyzed rectal neuroendocrine neoplasm patients diagnosed and treated at the Fourth Hospital of Hebei Medical University from February 2007 to May 2021. The clinicopathological characteristics of rectal multiple neuroendocrine neoplasms were summarized and analyzed in combination with 14 studies on rectal multiple neuroendocrine neoplasms.

RESULTS

The incidence of RM-NENs accounted for 3.8% of all R-NENs in this study. The number of tumors varied to some extent, the size of tumors was basically no more than 10 mm, and there were more G1 grade tumors. In the analysis of 46 cases with known lymph node metastasis, the difference in lymph node metastasis rate between the number of tumors < 8 and ≥ 8 was statistically significant (p = 0.002).

CONCLUSIONS

The incidence of rectal multiple neuroendocrine neoplasms accounted for 3.8% of all rectal neuroendocrine neoplasms. For rectal multiple neuroendocrine neoplasms, the lymph node metastasis rate was higher when the number of tumors was ≥ 8. The influence of the number of tumors on lymph node metastasis should be considered in the selection of treatment.

Efficacy of Endoscopic Resection for Rectal Neuroendocrine Tumors Smaller than 15 mm

BACKGROUND

Local resection, including endoscopic resection, is recommended for rectal neuroendocrine tumors (NETs) < 15 mm in patients without risk factors for metastasis, though the short- and long-term outcomes are unclear.

AIMS

This study investigates the efficacy of endoscopic resection for rectal NETs < 15 mm.

METHODS

The short- and long-term outcomes of patients with rectal NETs < 15 mm who underwent endoscopic resection and the outcomes of each endoscopic technique were analyzed. The tumors were stratified as < 10 mm (small-size group, SSG) and 10-14 mm (intermediate-size group, IMG).

RESULTS

Overall, 139 lesions (SSG, n = 118; IMG, n = 21) were analyzed. All tumors were classified as G1 (n = 135) or G2 (n = 4) according to the 2019 World Health Organization grading criteria. The complete resection rate was not different between the groups (P = 0.151). Endoscopic submucosal dissection (ESD) and endoscopic submucosal resection with a ligation device (ESMR-L) achieved complete resection rates > 90% in the SSG. The ESMR-L procedure time (P < 0.001) and hospitalized period (P < 0.001) were significantly shorter than those of ESD. ESD achieved a complete resection rate of 80.0% in the IMG. The tumor size did not affect the overall survival or rate of lymph node/distant metastases.

CONCLUSIONS

Endoscopic resection is a feasible and effective treatment for patients with rectal NETs < 15 mm without the risk factors of metastasis. ESMR-L and ESD are optimal techniques for resecting tumors smaller than 10 mm and 10-14 mm, respectively.

Comparison of the efficacy of endoscopic submucosal dissection and transanal endoscopic microsurgery in the treatment of rectal neuroendocrine tumors ≤ 2 cm

INTRODUCTION

Currently, complete tumor resection is considered the most effective treatment for rectal neuroendocrine tumors (NETs). Endoscopic submucosal dissection (ESD) and transanal endoscopic microsurgery (TEM) are recommended for rectalNETs ≤2 cm, but it is not clear which method is better. Thus, we evaluated the efficacy of ESD and TEM in the treatment of rectal neuroendocrine tumors (NETs) ≤ 2 cm.

METHODS

We conducted a single-centre retrospective cohort study between 2010 and 2021 of rectal NETs ≤ 2 cm in 114 patients with long-term follow-up data who were divided into ESD (n=55) and TEM groups (n=59). Our study assessed differences between groups in the complete resection rate of lesions, recurrence rate, surgical complications, procedure time, and length of hospital stay.

RESULTS

The co-primary outcomes were the complete resection rate of lesions and the recurrence rate. Compared to that in the ESD group, the complete resection rate was significantly higher in the TEM group (91.5% vs. 70.9%, p=0.005). The median follow-up time was 22 months in our study, and the follow-up outcomes suggested that the rates of recurrence were 1.8% (1/55) and 6.8% (4/59) in the ESD and TEM groups, respectively, with no significant difference between the two groups. The secondary outcomes of the evaluation were surgical complications, procedural time, and length of hospital stay. The rate of complications (gastrointestinal bleeding and perforation) was low in both the ESD (7.3%, 4/55) and TEM (5.1%, 3/59) groups. No difference in hospitalization duration was observed between the two groups in our study. However, the procedure time was significantly shorter in the ESD group than in the TEM group (27.5 min vs. 56 min, p<0.001).

CONCLUSIONS

Although the rate of complete resection in the TEM group was higher than that in the ESD group, there was no difference in recurrence rates between the two modalities during long-term follow-up. Depending on the qualities of the available hospital resources in the area, one of the two approaches can be adopted.