Is en bloc resection essential for endoscopic resection of GI neoplasia?

Endoscopic mucosal resection with double band ligation versus endoscopic submucosal dissection for small rectal neuroendocrine tumors

BACKGROUND

Endoscopic resection remains an effective method for the treatment of small rectal neuroendocrine tumors (NETs) (≤ 10 mm). Moreover, endoscopic mucosal resection (EMR) with double band ligation (EMR-dB), a simplified modification of EMR with band ligation, is an alternative strategy to remove small rectal NETs.

AIM

To evaluate the feasibility and safety of EMR-dB for the treatment of small rectal NETs (≤ 10 mm).

METHODS

A total of 50 patients with small rectal NETs, without regional lymph node enlargement or distant metastasis confirmed by endoscopic ultrasound, computerized tomography scan, or magnetic resonance imaging, were enrolled in the study from March 2021 to June 2022. These patients were randomly assigned into the EMR-dB (n = 25) group or endoscopic submucosal dissection (ESD) group (n = 25). The characteristics of the patients and tumors, procedure time, devices cost, complete resection rate, complications, and recurrence outcomes were analyzed.

RESULTS

There were 25 patients (13 males, 12 females; age range 28-68 years old) in the EMR-dB group, and the ESD group contained 25 patients (15 males, 10 females; age range 25-70 years old). Both groups had similar lesion sizes (EMR-dB 4.53 ± 1.02 mm, ESD 5.140 ± 1.74 mm; P = 0.141) and resected lesion sizes(1.32 ± 0.52 cm vs 1.58 ± 0.84 cm; P = 0.269). Furthermore, the histological complete resection and en bloc resection rates were achieved in all patients (100% for each). In addition, there was no significant difference in the complication rate between the two groups. However, the procedure time was significantly shorter and the devices cost was significantly lower in the EMR-dB group. Besides, there was no recurrence in both groups during the follow-up period.

CONCLUSION

The procedure time of EMR-dB was shorter compared with ESD, and both approaches showed a similar curative effect. Taken together, EMR-dB was a feasible and safe option for the treatment of small rectal NETs.

A colonoscopic overtube system that creates a 'therapeutic zone' and permits retraction facilitates endoscopic submucosal dissection, was associated with fewer deep bowel wall injuries and instrument exchanges, and required less lifting solution vs classic endoscopic submucosal dissection in an ex vivo bovine model

INTRODUCTION

Endoscopic submucosal dissection (ESD) is the 'gold standard' for large flat polyps; nevertheless, the rate of adoption in the USA is low. In ESD, the polyp is 'surgically' detached with a needle knife after a submucosal lift; gravity and the dissection cap are used for retraction. ESD would be easier if active retraction were possible. In an ex vivo bovine colon model, this study assessed an overtube system (Boston Scientific ORISE Tissue Retraction System, TRS) that permits retraction and creates 'an operative field' for removal of rectal/sigmoid lesions.

METHOD

Classic ESD (C-ESD) was compared to TRS-facilitated ESD (TRS-ESD). Cleaned/preserved bovine large bowel was used, and two 2-cm 'lesions'/colon were branded onto the mucosal surface 25 and 35 cm from the anus. Submucosal saline lifts were made using a thin catheter and a standard needle knife. We tracked case length, number of instrument exchanges (to refresh lift), the volume of lift solution, the fullness of resection, and deep muscle injuries.

RESULTS

Fifty ESDs were carried out in 25 colons (25 C-ESD, 25 TRS-ESD). Complete resections were noted in all cases. The TRS method required fewer instrument exchanges (median 5) vs C-ESD (median 9, p < 0.0001) and less lift solution (median 39 ml) than the C-ESD cases (median 55 ml, p = 0.0003). TRS-ESD was associated with fewer deep muscle injuries (median 2) than C-ESD (median 3, p = 0.0191). Finally, the TRS group's median case length (34.5 min) was shorter than that of C-ESD (41 min, p = 0.0543).

CONCLUSION

The TRS system provides retraction and facilitates ESD regarding the number of lift injections, the volume of lift solution needed, and avoidance of muscle injuries. Of note, there is an apparent TRS learning curve, and the device mandates a distal-to-proximal approach and initial 360 degree mucosal incision. Further study is warranted.

Hybrid endoscopic submucosal dissection (ESD) compared with conventional ESD for colorectal lesions: a systematic review and meta-analysis

BACKGROUND

Hybrid endoscopic submucosal dissection (ESD) is increasingly utilized to overcome the complexity of conventional ESD. This systematic review and meta-analysis evaluated the efficacy and safety of hybrid ESD for treatment of colorectal lesions.

METHODS

Search strategies were developed in accordance with PRISMA guidelines. Pooled proportions were calculated with rates estimated using random effects models. Measured outcomes included en bloc resection, procedure-associated complications, recurrence, and need for surgery. Subgroup analyses were performed to compare effectiveness of conventional versus hybrid ESD.

RESULTS

16 studies (751 patients) were included with a mean (standard deviation [SD]) lesion size of 27.96 (10.55) mm. En bloc resection rate was 81.63 % (95 % confidence interval [CI] 72.07 - 88.44; I2  = 80.89). Complications, recurrences, and need for surgery occurred in 7.74 % (95 %CI 4.78 - 12.31; I2  = 65.84), 4.52 % (95 %CI 1.40 - 13.65; I2  = 76.81), and 3.64 % (95 %CI 1.76 - 7.37; I2  = 15.52), respectively. Mean procedure duration was 48.83 (22.37) minutes. On subgroup analyses comparing outcomes for conventional (n = 1703) versus hybrid ESD (n = 497), procedure duration was significantly shorter for hybrid ESD (mean difference 18.45 minutes; P = 0.003), with lower complication rates (P = 0.04); however, hybrid ESD had lower en bloc resection rates (P < 0.001). There was no difference in rates of recurrence or surgery (P > 0.05).

CONCLUSION

While hybrid ESD was safe and effective for removal of colorectal lesions, with shorter procedure duration, fewer complications, and no difference in recurrence versus conventional ESD, hybrid ESD was associated with a lower en bloc resection rate.

Endoscopic submucosal dissection versus endoscopic mucosal resection for rectal carcinoid tumor. A meta-analysis and meta-regression with single-arm analysis

OBJECTIVE

As there has been so far no consensus on the best endoscopic resection technique, a meta-analysis was conducted to compare the efficacy and safety of endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) for treating rectal carcinoid tumors.

METHODS

MEDLINE and EMBASE databases were searched for articles on the treatment of rectal carcinoid tumors using ESD vs EMR published up to October 2020 for outcomes including en bloc and complete resection, margin involvement, procedure time, requirement for additional surgery, bleeding, perforation and recurrence. Risk ratio and weighted mean differences were used for a DerSimonian and Laird random effects pairwise meta-analysis. Single-arm meta-analyses of proportions and random effects meta-regression analysis were also conducted.

RESULTS

Twenty-two studies involving 1360 rectal carcinoid tumors were included, in which 655 and 705 rectal carcinoid tumors were resected with ESD and EMR, respectively. The resection efficacy of ESD was comparable to that of EMR for tumors <10 mm. However, there were a significantly higher complete resection rate, and lower rates of vertical margin involvement and requirement for additional surgery using ESD than using EMR for tumors ≤20 mm. ESD had a longer procedure time and an increased likelihood of bleeding than EMR.

CONCLUSIONS

ESD is more effective in providing a curative treatment for rectal carcinoid tumors ≤20 mm in size as ESD can achieve a higher complete resection rate with lower vertical margin involvement than EMR. While they are suitable for treating rectal carcinoid tumors <10 mm as both techniques provide similar efficacy.

Efficacy of novel sedation using the combination of dexmedetomidine and midazolam during endoscopic submucosal dissection for esophageal squamous cell carcinoma

BACKGROUND

Endoscopic submucosal dissection (ESD) is the preferred treatment for esophageal squamous cell carcinoma (ESCC). However, ESD can be difficult when patients move due to insufficient sedation. We conducted a prospective confirmatory single arm study to evaluate the efficacy of using dexmedetomidine (DEX) in combination with midazolam as a novel sedation for ESD.

METHODS

Endoscopic submucosal dissection was performed without intubation in 65 patients. The primary outcome was the proportion of patients who did not move or require restraint during ESD, compared to historical control of ESD performed under midazolam sedation. Secondary outcomes included the frequency of complications and self-report questionnaires from patients and endoscopists.

RESULTS

Restraint was not required in 97% of patients sedated using the combination of DEX and midazolam. Depressed respiration, low blood pressure, and bradycardia occurred in 23, 37, and 26% of patients, respectively. All patients recovered without severe complication. Occurrence of low blood pressure and bradycardia were higher, while respiratory depression was lower for the combination group than for the historical control group. The amount of midazolam used was significantly lower than in the control. Of note, 94% of patients had no painful sensations, with 3 reporting chest pain and 3 having a recollection of the procedure. Endoscopists were satisfied with the sedation in 94% of cases. All lesions were resected in en bloc fashion, without perforation.

CONCLUSIONS

The combination of DEX and midazolam provided effective sedation for ESD for ESCC.

Therapeutic outcomes of endoscopic submucosal dissection of differentiated early gastric cancer in a Western endoscopy setting (with video)

BACKGROUND

Large multicenter gastric cancer endoscopic submucosal dissection (ESD) studies conducted at major Japanese institutions have reported en bloc resection, en bloc tumor-free margin resection, and curative resection rates of 92.7% to 96.1%, 82.6% to 94.5%, and 73.6% to 85.4%, respectively, with delayed bleeding and perforation rates of 0.6% to 6.0% and 3.6% to 4.7%, respectively. Although ESD is currently an alternative treatment in some countries, particularly in Asia, it remains uncertain whether ESD therapeutic outcomes in Western endoscopy settings can be comparable to those achieved in Japan.

OBJECTIVE

To evaluate the ESD therapeutic outcomes for differentiated early gastric cancer (EGC) in a Western endoscopy setting.

DESIGN/SETTING

Consecutive case series performed by an expertly trained Western endoscopist.

PATIENTS

Fifty-three patients with 54 lesions.

INTERVENTIONS

ESD for early gastric cancers (T1) satisfying expanded inclusion criteria.

MAIN OUTCOME MEASUREMENTS

En bloc resection, en bloc tumor-free margin resection, and curative resection rates were 98%, 93%, and 83%, respectively. The delayed bleeding rate was 7%, and the perforation rate was 4%.

RESULTS

The mean patient age was 67 years, and the mean tumor size was 19.8 mm, with 54% of the lesions located in the lesser curvature. The median procedure time was 61 minutes, with ESD procedures 60 minutes or longer associated with submucosal fibrosis (P < .001) and tumor size 25 mm or larger (P = .03). In every ESD procedure, both circumferential incision and submucosal dissection were performed by using a single knife. Two of the 4 delayed bleeding cases required surgery, and all perforations were successfully managed by using endoscopic clips.

LIMITATION

Long-term outcome data are currently unavailable.

CONCLUSION

ESD for differentiated EGC resulted in favorable therapeutic outcomes in a Western endoscopy setting comparable to those achieved at major Japanese institutions.

Endoscopic Resection for Early Gastric Cancer beyond Absolute Indication with Emphasis on Controversial Issues

Endoscopic resection is the established treatment for early gastric cancer in selected patients with negligible risk of lymph node metastasis ('absolute indication'). Based on clinical observations and large pathological databases, expanding indications for endoscopic resection beyond absolute indication has been tried in Japan and Korea. However, controversies exist regarding the safety of treating early gastric cancer beyond absolute indication in terms of pathological evaluation of the resected specimen, definition of expanded indication, discrepancy between pre-endoscopic resection and post-endoscopic resection diagnoses of gastric neoplasm, and the best strategy for cases with non-curative resection. In this brief review, current evidence and clinical experience regarding issues of endoscopic resection beyond absolute indication will be summarized.

Current status of endoscopic resection strategy for large, early colorectal neoplasia in Japan

BACKGROUND

Conventional endoscopic resection (CER) for early colorectal neoplasia (CRN) is widely accepted as a minimally invasive treatment. Endoscopic submucosal dissection (ESD) was developed in Japan to resect larger lesions, but ESD was not covered by the Japanese national health insurance until April 2012. In addition, treatment strategies vary considerably among medical facilities. To evaluate the current situation in Japan regarding endoscopic treatment of CRNs measuring ≥20 mm, we conducted a prospective multicenter study at 18 medium-volume and high-volume specialized facilities in cooperation with the Japan Society for Cancer of the Colon and Rectum (JSCCR).

METHODS

The JSCCR conducted a multicenter, observational study of all patients treated by CER and ESD of CRNs measuring ≥20 mm.

RESULTS

From October 2007 to December 2010, CERs and ESDs were performed on 1,845 CRNs (CERs 1,029; ESDs 816). Lesions diagnosed as protruded, flat, and depressed totaled 541, 1224, and 48, respectively. En bloc resection rates and mean procedure times for CER/ESD were 56.9%/94.5% (P < 0.01) and 18 ± 23 min/96 ± 69 min, respectively. The average ESD procedure time was 129 ± 83 min in the ≥40-mm group. As lesion size increased, the CER en bloc resection rate decreased significantly (trend P < 0.01), but the ESD en bloc resection rate remained over 93%. Perforation and delayed bleeding rates of CER/ESD were 0.8%/1.6% (P < 0.05) and 2%/2.2% (P = 0.3), respectively.

CONCLUSIONS

The en bloc resection rate for ESD was significantly higher than for CER, although complication rates were fairly low. Despite a longer procedure time, safety of colorectal ESD has improved in various facilities in Japan. However, ESD for lesions measuring ≥40 mm must be performed by experienced endoscopists due to the longer procedure time.

Gastric endoscopic submucosal dissection assisted by a new traction method: the clip-band technique. A feasibility study in a porcine model (with video)

BACKGROUND

Endoscopic submucosal dissection (ESD) is the standard of care for treating gastric intramucosal neoplasias in Japan. However, it is seldom performed in Western countries, mainly because it is technically very challenging. Several traction methods have been proposed to facilitate submucosal dissection, but they are usually not widely available or are difficult to apply.

OBJECTIVE

Our main aim was to evaluate the feasibility of a new method, the clip-band technique, for improving the visualization of the submucosal layer during ESD.

DESIGN

Observational, experimental, feasibility study conducted in a porcine model.

SETTING

University Hospital of the Canary Islands, Research Animal Laboratory.

PATIENTS

Animal study.

INTERVENTIONS

After completion of the circumferential cutting, a clip-band traction system was applied.

MAIN OUTCOME MEASUREMENTS

Efficacy and safety of the clip-band technique.

RESULTS

Eighteen ESDs performed in live domestic pigs were completed without any serious complications. The mean specimen size was 35.38 ± 12.17 mm, the mean cutting time was 13.06 ± 10.52 minutes, and the mean dissection time was 16.67 ± 9.01 minutes.

LIMITATIONS

The clip-band technique was not compared with the standard ESD technique.

CONCLUSIONS

This initial study shows that the clip-band traction technique is feasible and that it permits safe, effective, and relatively inexpensive gastric ESD.

Clinical outcomes of endoscopic submucosal dissection for undifferentiated early gastric cancer

BACKGROUND

Early gastric cancer (EGC) with undifferentiated histology has not been generally accepted as an indication for endoscopic treatment. This study was designed to evaluate the outcomes and clinicopathological factors associated with the complete resection of undifferentiated EGC using endoscopic submucosal dissection (ESD).

METHODS

A retrospective analysis of prospectively collected data was performed on consecutive patients who underwent ESD. Among the 456 EGCs treated using ESD at the Seoul National University Hospital, Seoul, Korea, between April 2005 and June 2008, 60 lesions (13.2%) were diagnosed as undifferentiated gastric cancer (poorly differentiated adenocarcinoma or signet ring cell carcinoma).

RESULTS

En bloc resection was performed in all lesions without significant complications. The size discrepancy between the pretreatment endoscopy and the resected specimen was significantly higher in undifferentiated EGCs than differentiated EGCs (p = 0.002). The complete resection rate was significantly lower for undifferentiated EGC (55%) cases than differentiated EGC cases (84.1%; p < 0.001). Independent risk factors for incomplete resection of undifferentiated EGC included tumor size >20 mm, submucosal invasion, and presence of ulceration. During a mean observation time of 16 months, no recurrence developed in any of the patients with undifferentiated EGCs thought to be completely resected by ESD.

CONCLUSIONS

ESD might be considered an alternative treatment modality in carefully selected cases of undifferentiated EGC.