Saline-assisted endoscopic resection of rectal carcinoids: cap aspiration method versus simple snare resection

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.

Endoscopic mucosal dissection for multiple rectal carcinoids: A case report

BACKGROUND

Multiple rectal carcinoids have a low incidence clinically. Curative resection can be achieved by endoscopy, but there is a risk of missing the lesion. Postoperative follow-up is very important.

CASE SUMMARY

A patient was diagnosed with multiple rectal carcinoids and hemorrhoids by colonoscopy due to repeated hematochezia for more than 2 mo. After chest, abdominal and pelvic contrast-enhanced CT examinations were completed to exclude carcinoid metastasis, endoscopic lesion resection was performed. A total of eight lesions were completely removed. Postoperative pathology and immunohistochemistry confirmed carcinoids, classified as G1. No new lesions were found by colonoscopy 3 mo after operation.

CONCLUSION

For multiple rectal carcinoids smaller than 1 cm, endoscopic dissection can be curative, but close follow-up should be performed.

Comparison between endoscopic mucosal resection with a cap and endoscopic submucosal dissection for rectal neuroendocrine tumors

Background

The aim of this study is to evaluate and compare the safety and efficacy of endoscopic mucosal resection with a cap (EMR-c) with those of endoscopic submucosal dissection (ESD) for rectal neuroendocrine tumors (R-NETs) ≤ 15 mm in diameter, and to analyze the risk factors of incomplete resection.

Methods

A total of 122 patients who underwent EMR-c or ESD for R-NETs at the Fourth Hospital of Hebei Medical University between February 2007 and December 2020 were invovled in this study. The clinical outcomes of two groups were compared and evaluated.

Results

A total of 122 patients with 128 R-NETs underwent endoscopic resection (EMR-c, 80; ESD, 48). In terms of duration of operation, EMR-c was significantly shorter than ESD (p < 0.001). Univariate analysis and multivariate analysis suggested that tumor diameter ≥ 8 mm was an independent risk factor for incomplete resection in patients with R-NETs in this study.

Conclusions

Both EMR-c and ESD were safe and effective treatments for R-NETs ≤ 15 mm in diameter. In addition, tumor diameter ≥ 8 mm was an independent risk factor for incomplete resection.

Ligation-assisted endoscopic mucosal resection has high complete resection rate in rectal carcinoid tumor

AIM

We aimed to compare the outcomes of different therapeutic modalities in rectal carcinoid tumors.

METHOD

We retrospectively collected 145 patients with rectal carcinoid tumors which were pathologically diagnosed from 2005/01/01 to 2016/12/31. We compared tumor size, complete resection rate and recurrent rate between different therapeutic modalities. Then, prospectively compared the treatment outcomes of 28 patients treated with ligation assisted endoscopic mucosal resection (LEMR) and 25 patients treated with endoscopic mucosal resection with cap (EMRC).

RESULT

The mean size of tumors was 6.5 mm (1-25 mm), and the mean follow-up duration was 26 months (6-118 months). The therapeutic modalities included ligation-assisted endoscopic mucosal resection (LEMR) (25 tumors, 17%), endoscopic mucosal resection (EMR) (31 tumors, 21%), snare polypectomy (30 tumors, 21%), biopsy forceps removal (46 tumors, 32%) and surgical resection (13 tumors, 11%), including 6 tumors treated with transanal endoscopic microsurgery (TEM) method. In view of pathologically complete resection rate, LEMR was highest (100%), followed by surgical resection (85%). However, EMR only had 42% pathologically complete resection rate. Besides, LEMR and surgical resection had no local recurrence and significantly higher clinically complete resection rate, compared to other treatments. For the further prospective study, complete resection was noted in 28 (100%) patients in LEMR group and 13 (52%) patients in EMRC group.

CONCLUSION

In the treatment of rectal carcinoid tumors, LEMR is safe and effective compared with traditional endoscopic treatments.

Favorable long-term outcomes of endoscopic resection for nonampullary duodenal neuroendocrine tumor

BACKGROUND AND AIM

The long-term outcomes of endoscopic resection for nonampullary duodenal neuroendocrine tumors are limited. We aimed to clarify it.

METHODS

Consecutive patients with nonampullary duodenal neuroendocrine tumors endoscopically treated at our institute between January 2005 and June 2020 were included in this retrospective study. En bloc and R0 resection rates and adverse events were evaluated as short-term outcomes of endoscopic resection. The 5-year overall and recurrence-free survival rates of patients after endoscopic resection were calculated as long-term outcomes.

RESULTS

Of 34 patients with 34 lesions, 33 patients (97%) underwent endoscopic mucosal resection, and one (3%) underwent endoscopic submucosal dissection. En bloc resection was achieved in 33 lesions (97%). R0 resection was achieved in 20 lesions (59%). The median tumor size was 6 mm (range: 3-13). Thirty-one lesions (91%) and three lesions (9%) were classified as G1 and G2, respectively. Lymphovascular invasion was observed in six lesions (18%). Intraprocedural perforation occurred in four patients (12%) who were conservatively treated with endoscopic closure. All 34 patients were followed up without additional treatment after endoscopic resection, and no recurrence or metastasis developed during the median follow-up period of 47.9 months (range: 9.0-187.1). The 5-year overall survival and recurrence-free survival rates were 87.1% and 100%, respectively.

CONCLUSIONS

Endoscopic resection provided a favorable long-term prognosis for patients with nonampullary duodenal neuroendocrine tumors without lymph node metastasis.

Comparison of conventional and modified endoscopic mucosal resection methods for the treatment of rectal neuroendocrine tumors

BACKGROUND/AIM

Small rectal neuroendocrine tumors (NETs) confined to the submucosa are endoscopically resectable. Because most rectal NETs are submucosal tumors, conventional endoscopic mucosal resection (cEMR) may not result in a complete resection. This study investigated whether modified EMRs, namely endoscopic submucosal resection with ligation (ESMR-L), EMR with precutting (EMR-P), and strip biopsy are superior to cEMR for achieving histologically complete resection (HCR) of rectal NETs.

METHODS

Medical records of 215 patients who were treated with endoscopic resections for rectal NETs between January 2011 and July 2019 were retrospectively enrolled. Of the patients, 110, 33, 29, and 43 underwent cEMR, ESMR-L, EMR-P, and strip biopsy, respectively. For each method, HCR and en bloc resection rates, procedure times, and complication rates were measured.

RESULTS

HCR was achieved with cEMR, EMR-P, ESMR-L, and strip biopsies for 74.5%, 90.9%, 93.1%, and 90.7% of cases, respectively. The HCR rate for cEMR was inferior to those of the modified EMRs (p = 0.045 for cEMR vs. EMR-P; p = 0.031 for cEMR vs. ESMR-L; p = 0.027 for cEMR vs. strip biopsy). Among the three modified EMRs, there was no significant difference in achieving HCR (p = 1.000). En bloc resection (p = 0.096) and complication rates (p = 0.071) were not significantly different among the four EMR methods, although EMR-P required the longest procedure time (p = 0.000).

CONCLUSIONS

All three modified EMRs are superior to cEMR and are equally effective for achieving HCR of rectal NETs.

Relevant risk factors and the prognostic impact of positive resection margins after endoscopic resection of gastrointestinal neuroendocrine tumors

Introduction

Endoscopic resection for the treatment of gastrointestinal neuroendocrine tumors has a risk of resection margin residues. The related risk factors and prognosis of post-endoscopic resection margin residues have not been fully evaluated.

Aim

To investigate the associated risk factors and prognostic impact of resection margin residues after endoscopic resection of gastrointestinal neuroendocrine tumors.

Material and methods

We conducted a retrospective analysis of 129 patients who underwent endoscopic resection for the treatment of gastrointestinal neuroendocrine tumors. Sex, age, location, diameter of tumor, depth of invasion, endoscopic treatment methods, endoscopic ultrasonography (EUS) evaluation, and the work experience of endoscopists were evaluated as potential risk factors. In addition, the prognoses of patients with positive resection margins were analyzed.

Results

A total of 18 (18/129, 14.0%) patients exhibited positive resection margins after endoscopic resection. Among 16 successfully followed-up patients, 1 died due to rupture of pulmonary artery aneurysms, 2 underwent supplementary surgical operations, and 2 underwent additional endoscopic submucosal dissection. The remaining 11 patients were periodically followed up, and no recurrences were found. The results of univariate analysis suggested that endoscopic treatment method, the depth of invasion, and EUS evaluation correlated with positive resection margin. Multivariate regression analysis suggested that the depth of invasion and EUS evaluation were risk factors for resection margin residues.

Conclusions

The depth of invasion and EUS evaluation are independent risk factors for positive resection margins after endoscopic resection. This finding suggests that a greater depth of invasion increases the risk for positive resection margins, while EUS evaluation before resection decreases this risk.

Endoscopic, transanal, laparoscopic, and transabdominal management of rectal neuroendocrine tumors

Rectal neuroendocrine tumors (RNET) are rare tumors but their prevalence is constantly increasing due to a prolonged survival and rising incidence related to a growing number of colonoscopies and improved knowledge. Their main prognostic determinant is tumor stage. While most RNET are localized, their management should be tailored depending on the presence or absence of the factors predictive of lymph-node metastases including tumor size, endoscopic aspect, T stage, grade and lymphovascular invasion. Endoscopic ultrasonography is the most relevant technique for locoregional assessment. Low-risk RNET can be treated using advanced endoscopic resection techniques or transanal endoscopic microsurgery, in expert centers because they require technicity and experience. Conversely, radical surgery with lymphadenectomy should be proposed in the presence of any pejorative factor. The long-term evolution of RNET remains to be specified, and prospective studies should be conducted in order to determine the relevance of the current management strategies.

Pocket Creation Method of Endoscopic Submucosal Dissection to Ensure Curative Resection of Rectal Neuroendocrine Tumors

Purpose

Pancreatic/gastrointestinal tract neuroendocrine neoplasm (NEN) is divided into neuroendocrine tumor (NET) and neuroendocrine carcinoma (NEC) according to the grade of malignancy, and differences are seen in clinical prognosis. NET, and rectal NET in particular, is often treated endoscopically. Endoscopic mucosal resection (EMR) was previously the main intervention for rectal NET, but EMR with a ligation device (EMR-L) and endoscopic submucosal dissection (ESD) are now also used. However, complete resection with these therapies is not always achieved. The pocket creation method (PCM) is a safe ESD method for colon tumors that offers a high en bloc resection rate compared with conventional colonic ESD. We performed ESD using the PCM for rectal NET and evaluated the complete resection rate.

Methods

We performed ESD using the PCM in 4 patients. This procedure was technically feasible in all patients.

Results

Endoscopically, all cases were resected en bloc, and pathological complete resection was achieved in all cases. No complications such as perforation or delayed postoperative bleeding were encountered.

Conclusions

PCM should be considered when treating NET of appropriate size.

The clinical outcomes and risk factors associated with incomplete endoscopic resection of rectal carcinoid tumor

BACKGROUND AND AIM

The risk of lymph node metastasis of a small rectal carcinoid tumor (<10 mm) is known to be lower than that of tumors at other gastrointestinal sites. Although rectal carcinoid tumors can be treated by endoscopic resection, the resected specimen may be incomplete. The consequences of an incomplete resection are not well known.

METHOD

From December 2008 to November 2015, cases of rectal carcinoid tumors resected by endoscopic resection techniques such as endoscopic submucosal dissection (ESD), or endoscopic mucosal resection using band ligation device (EMR-L), or cap aspiration (EMR-C) were enrolled. The factors associated with incomplete endoscopic resection and clinical outcomes were retrospectively analyzed.

RESULTS

During the study period, a total of 134 rectal carcinoid tumors were resected by endoscopic techniques; ESD (n = 53), EMR-C (n = 65), and EMR-L (n = 16). The mean tumor size was 5.5 ± 2.4 mm. The mean follow-up period was 835 ± 501 days. The en bloc resection and complete resection rates were 100 and 85.8%, respectively. Procedure time was longer and the size of the resected tumor was larger in the ESD group than in the EMR-C or EMR-L (p < 0.001) group by the univariate analysis. A factor related to incomplete resection was central depression on the surface (OR 11.529, 95% CI 2.377-55.922, p = 0.002), as revealed by the multivariate analysis. Nineteen patients had an incomplete resection status and did not undergo additional resection treatment; none of these patients had recurrence during the study period.

CONCLUSIONS

A rectal carcinoid tumor with a central depression on the surface was associated with a higher incomplete resection rate. After an incomplete resection of small rectal carcinoid tumors, without evidence of lymphovascular invasion, a periodic follow-up examination without additional resection may be recommended.

Evaluation of treatment for rectal neuroendocrine tumors sized under 20 mm in comparison with the WHO 2010 guidelines

Rectal neuroendocrine tumor (NET) is a relatively rare lesion of the gastrointestinal tract, but the prospective examination with colonofiberoscopy or endoscopic ultrasound has increased the frequency of its detection. It is often difficult to determine the optimal treatment for NETs sized <20 mm in the clinical setting. Other clinicopathological variables are not considered in the current guidelines and staging systems. Although the effects of lymphovascular invasion are not covered by the World Health Organization (WHO) 2010 guidelines or tumor-node-metastasis (TNM) staging system, this may be promising for the establishment of improved guidelines and staging systems, particularly for early-stage colorectal carcinoids. The aim of the present study was to evaluate rectal NETs sized <20 mm in comparison with the WHO 2010 guidelines. Between January 2005 and December 2013, 40 consecutive patients [26 men and 14 women; median age, 59.3 years (range, 34-81 years)] who underwent endoscopic resection of rectal NETs, and 12 patients undergoing surgical resection of rectal NETs, were enrolled in this retrospective study. The median tumor size was 7.4 mm (range, 3-15 mm). The locations of the NET were the rectosigmoid colon (n=3), the upper rectum (n=13), and the lower rectum (n=25). The NETs were classified by size as 0-5 (n=7), 6-10 (n=29) and 11-15 mm (n=4). The surgical procedures performed included low anterior resection plus esophagectomy (n=1), laparoscopic low anterior resection (n=7) and laparoscopic intersphincteric resection (n=4). Only 1 patient had lymph node metastasis (tumor sized 6-10 mm, with lymphovascular invasion). NET recurrence was not detected in any of the patients. According to the WHO guidelines, the tumors were classified as grade (G)1 (n=8), G2 (n=3) and G1/G2 (n=1). The tumor in the patient with lymph node metastasis was G1. NETs sized <10 mm may be curatively treated by endoscopic resection. However, NETs with either lymphovascular invasion or sized >1 cm carry a risk for metastasis equivalent to that of adenocarcinomas. Therefore, it is mandatory to histologically examine lymphovascular invasion in specimens retrieved via endoscopic resection to determine the necessity for further radical surgery with regional lymph node dissection. The treatment of NETs sized <20 mm as presently defined in the WHO 2010 guidelines requires further evaluation.

Short- and long-term outcomes of endoscopic resection of rectal neuroendocrine tumours: analyses according to the WHO 2010 classification

OBJECTIVE

Although the World Health Organisation (WHO) defined a novel classification of gastroenteropancreatic neuroendocrine tumours (NETs) in 2010, indications for endoscopic resection of rectal NETs in the guidelines were based on evidence accumulated for carcinoid tumours defined by a previous classification. This study was designed to clarify indications for endoscopic resection of rectal NETs corresponding to the new WHO classifications.

MATERIAL AND METHODS

One hundred-seventy rectal NETs resected endoscopically from April 2001 to March 2012 were histologically re-classified according to the WHO 2010 criteria. The clinicopathological features of these lesions were analysed, and the short- and long-term outcomes of endoscopic resection were evaluated.

RESULTS

Of the 170 rectal NETs, 166 were histopathologically diagnosed as NET G1 and four as NET G2. Thirty-eight tumours (22.4%) were positive for lymphovascular invasion, a percentage higher than expected. Although the curative resection rate was low (65.3%), en bloc (98.8%) and complete (85.9%) resection rates were high. Modified endoscopic mucosal resection (88.0%) and endoscopic submucosal dissection (92.2%) resulted in significantly higher complete resection rates than conventional endoscopic mucosal resection (36.4%). No patient experienced tumour recurrence, despite the low curative resection rate.

CONCLUSION

Despite the low curative resection rate, prognosis after endoscopic resection of rectal NETs was excellent. Prospective large-scale, long-term studies are required to determine whether NET G2 and tumours >1 cm should be included in the indication for endoscopic resection and whether tumours with lymphovascular invasion can be followed up without additional surgery.

Endoscopic Resection for Small Rectal Neuroendocrine Tumors: Comparison of Endoscopic Submucosal Resection with Band Ligation and Endoscopic Submucosal Dissection

Background and Aims. There is no consensus so far regarding the optimal endoscopic method for treatment of small rectal neuroendocrine tumor (NET). The aim of this study was to compare treatment efficacy, safety, and procedure time between endoscopic submucosal resection with band ligation (ESMR-L) and endoscopic submucosal dissection (ESD). Methods. We conducted a prospective study of patients who visited Inha University Hospital for endoscopic resection of rectal NET (≦10 mm). Pathological complete resection rate, procedure time, and complications were evaluated. Results. A total of 77 patients were treated by ESMR-L (n = 53) or ESD (n = 24). En bloc resection was achieved in all patients. A significantly higher pathological complete resection rate was observed in the ESMR-L group (53/53, 100%) than in the ESD group (13/24, 54.2%) (P = 0.000). The procedure time of ESD (17.9 ± 9.1 min) was significantly longer compared to that of ESMR-L (5.3 ± 2.8 min) (P = 0.000). Conclusions. Considering the clinical efficacy, technical difficulty, and procedure time, the ESMR-L method should be considered as the first-line therapy for the small rectal NET (≤10 mm). ESD should be left as a second-line treatment for the fibrotic lesion which could not be removed using the ESMR-L method.

Cap-assisted EMR for rectal neuroendocrine tumors: comparisons with conventional EMR and endoscopic submucosal dissection (with videos)

BACKGROUND AND AIMS

The incidence of rectal neuroendocrine tumors (NETs) is increasing, and most small rectal NETs can be treated endoscopically. Cap-assisted EMR (EMR-C) was suggested as an effective treatment for rectal NETs in a few studies. We aimed to compare the outcomes of conventional EMR, EMR-C, and endoscopic submucosal dissection (ESD) for the treatment of rectal NETs.

METHODS

A total of 138 rectal NETs were treated endoscopically by a single endoscopist at Asan Medical Center. We analyzed 122 rectal NETs that had been removed by using EMR (n = 56), EMR-C (n = 34), or ESD (n = 32).

RESULTS

The histologic complete resection rate was higher in the EMR-C group than in the EMR group (94.1% vs 76.8%, P = .032). Intraprocedural bleeding tended to be more frequent in the EMR-C group than in the EMR group (8.8% vs 0%, P = .051). No differences in the rates of adverse events or histologic complete resections were observed between the EMR-C group and the ESD group for 6-mm to 8-mm NETs; however, the procedure time was significantly shorter in the EMR-C group (3.9 ± 1.1 minutes) than in the ESD group (19.0 ± 12.1 minutes) (P < .001). There was no recurrence in any of the 3 groups.

CONCLUSIONS

EMR-C is the preferable technique for endoscopic resection of small rectal NETs.

Cap-aspiration lumpectomy for small submucosal tumors originating from the muscularis propria of the gastric fundus: a preliminary study (with videos)

OBJECTIVE

Small fundal submucosal tumors (SMTs) originated from the muscularis propria pose great difficulties to conventional therapies. We aimed to evaluate the feasibility and safety of endoscopic cap-aspiration lumpectomy (CASL) as a new and simple full-thickness resection for the treatment of small fundal SMTs.

METHODS

From July 2013 to February 2014, patients with small fundal SMTs of ≤10 mm in diameter that were originated from muscularis propria were included in the study. CASL was performed by suctioning SMTs into a transparent cap, ligating with a metal snare and resecting the tumors. The wall deficit was closed by using endoclips.

RESULTS

Altogether 28 patients were included in the study. CASL achieved an en bloc resection rate of 100%, with a mean total procedure time of 23.9 min. Active perforation was found in 20 (71.4%) patients, and endoclips closed the wall defect in all 20 cases. One patient developed pneumoperitoneum and self-limited peritonitis was found in two patients, all of whom were managed successfully. Pathological examination showed that 71.4% (20/28) of the tumors were gastrointestinal stromal tumors. No tumor recurrence was observed during the follow-up.

CONCLUSIONS

CASL may be a feasible and safe full-thickness resection modality for the treatment of small fundal SMTs arising from the muscularis propria. Further randomized studies are needed to confirm the results.

Endoscopic submucosal dissection for the treatment of rectal carcinoid tumors 7-16 mm in diameter

OBJECTIVE

Small rectal carcinoid tumors (<10 mm) are often removed via endoscopic submucosal dissection (ESD). However, the use of ESD for tumors of an intermediate size (7-16 mm) is less well documented. This study aimed to evaluate the efficacy and safety of ESD compared with endoscopic mucosal resection using a cap (EMR-C) for the treatment of 7-16-mm rectal carcinoids.

MATERIAL AND METHODS

From September 2007 to August 2012, 55 patients with large rectal carcinoid tumors were treated by EMR-C (30 cases) or ESD (25 cases). The en bloc resection rate, pathological complete response (pCR) rate, procedure time, and incidence rates of complications, local recurrence, and distant metastasis were evaluated.

RESULTS

The basic and clinical characteristics of the patients in the two groups did not differ significantly (p > 0.05). The mean procedure time was longer for ESD than EMR-C (24.79 ± 4.89 vs. 9.52 ± 2.14 min, p < 0.001). The rates of en bloc resection and pCR were higher with ESD than with EMR-C (100 vs. 83.33 %, and 100 vs. 70.00 %, respectively). No patients in the EMR-C group experienced complications. However, in the ESD group, two cases of perforation occurred, and one patient experienced delayed bleeding. These complications were successfully managed via endoscopical therapy. Five cases of local recurrence were detected after EMR-C, whereas no patients experienced recurrence after ESD.

CONCLUSIONS

Compared with EMR-C, ESD appears to be a more favorable therapeutic option for the treatment of rectal carcinoid tumors less than 16 mm in diameter based on improved rates of pCR and local recurrence.

The effectiveness of endoscopic submucosal resection with a ligation device for small rectal carcinoid tumors: focused on previously biopsied tumors

PURPOSE

To evaluate the effectiveness of endoscopic submucosal resection with a ligation device (ESMR-L) on histologic complete resection for the treatment of small rectal carcinoid tumors in comparison with the treatment with endoscopic mucosal resection (EMR) alone.

METHODS

Thirty-five patients with small rectal carcinoid tumors were enrolled prospectively for ESMR-L, and we retrospectively reviewed 74 carcinoid tumor patients who underwent EMR. The comparison between ESMR-L and EMR groups was analyzed including endoscopic and histologic complete resection and complications after resection. We also evaluated the associations of histologic complete resection with clinical and procedure-related factors.

RESULTS

The histologic complete resection rate was significantly higher in ESMR-L than in EMR (94.3% vs. 75.7%, P=0.019). In addition, the resection time was significantly shorter in ESMR-L than in EMR (4.16±1.48 min vs. 5.11±2.47 min, respectively, P=0.014). Moreover, previously biopsied rectal carcinoid tumors were significantly associated with histologic incomplete resection, especially in patients who underwent EMR (odds ratio, 6.28; 95% confidence interval, 1.92-20.58; P=0.002).

CONCLUSIONS

Compared with EMR, ESMR-L is a safe and effective method for histologic complete resection of small rectal carcinoid tumors, especially in patients with previously biopsied carcinoid tumors.

Endoscopic submucosal dissection for rectal carcinoid tumour using the Clutch Cutter

BACKGROUND

To reduce the risk of complications related to endoscopic submucosal dissection (ESD) using knives, we developed the Clutch Cutter (CC), which can grasp and incise the target tissue similarly to biopsy techniques using an electrosurgical current. The aim of this study was to evaluate the efficacy and safety of ESD using the CC for removal of rectal carcinoid tumours.

METHODS

Between December 2009 and December 2011, we prospectively enrolled seven patients (seven lesions) on 7 different days. Patients were endoscopically diagnosed with rectal subepithelial lesions (upper rectum, n = 3; lower rectum, n = 4) within the level 3 layer and without lymph node involvement, with the diagnosis confirmed by preliminary endoscopy, endoscopic ultrasound and endoscopic biopsies. ESD using the CC was performed in all cases, and the therapeutic efficacy, safety and tumour recurrence were assessed.

RESULTS

All lesions were treated easily and safely, and there were no inadvertent incisions. En bloc resection was obtained in all cases, and histologic tumour-free lateral/basal margins were obtained in six of the seven patients. No delayed haemorrhage, perforation or tumour recurrence occurred.

CONCLUSION

ESD using the CC appears to be an easy, safe and technically efficient method for resecting rectal carcinoid tumour.

Which endoscopic treatment is the best for small rectal carcinoid tumors?

The incidence of rectal carcinoids is rising because of the widespread use of screening colonoscopy. Rectal carcinoids detected incidentally are usually in earlier stages at diagnosis. Rectal carcinoids estimated endoscopically as < 10 mm in diameter without atypical features and confined to the submucosal layer can be removed endoscopically. Here, we review the efficacy and safety of various endoscopic treatments for small rectal carcinoid tumors, including conventional polypectomy, endoscopic mucosal resection (EMR), cap-assisted EMR (or aspiration lumpectomy), endoscopic submucosal resection with ligating device, endoscopic submucosal dissection, and transanal endoscopic microsurgery. It is necessary to carefully choose an effective and safe primary resection method for complete histological resection.

Endoscopic resection for gastrointestinal neuroendocrine tumors

Gastrointestinal (GI) and neuroendocrine tumors (NETs) can be treated by mini-invasive endoscopic resection when localized in the superficial layers of the bowel wall and their size is <20 mm. Endoscopic diagnosis of NETs is usually incidental or suspected after clinical, laboratory or imaging findings. Endoscopic mucosal resection is the most commonly used technique for NET removal, endoscopic submucosal dissection is indicated in selected cases, while papillectomy is feasible for ampullary lesions. Histopathologic assessment of the resection margin (circumferential and deep) is important for staging. Incidence of endoscopic mucosal resection-/endoscopic submucosal dissection-related complications for removal of GI NETs are similar to those reported for other GI lesions. Endoscopic follow-up is based on histopathologic characteristics of the resected NETs and its site. NETs >20 mm in size, with penetration of the muscle layer and/or serosa are at high risk for metastases and surgical approach is recommended when feasible.

Treatment outcomes according to endoscopic treatment modalities for rectal carcinoid tumors

BACKGROUND

Despite a growing understanding of the clinical effectiveness of endoscopic treatment for small rectal carcinoid tumors, there is still controversy concerning the best endoscopic treatment for resecting rectal carcinoid tumors easily and effectively.

OBJECTIVES

The objective of the present study was to compare the therapeutic efficacy and safety of endoscopic submucosal resection with a ligation device (ESMR-L) with endoscopic submucosal dissection (ESD) for rectal carcinoid tumors. In addition, a conventional snare-based endoscopic mucosal resection (EMR) was included in the study and compared with both ESMR-L and ESD.

METHODS

A retrospective analysis was performed in 115 patients who underwent endoscopic resection of a rectal carcinoid tumor between January 2005 and June 2011. These patients were classified into three groups according to the type of endoscopic procedure: EMR group (n=33), ESMR-L group (n=40) and ESD group (n=44).

RESULTS

The complete resection rate of the EMR group was significantly lower than those of the ESMR-L and ESD groups (77.4 vs. 100 and 97.7%, P=0.002 and P=0.007). Tumor-free vertical margins were significantly greater in the ESMR-L and ESD groups than in the EMR group (ESMR-L and ESD vs. EMR group, P=0.013 and P=0.041). The curative resection rate of rectal carcinoid tumors in the EMR group was 77.4%, which was significantly lower than that of the ESMR-L (95%, 38/40) and EDS groups (97.7%, 43/44) (77.4% vs. 95%, P=0.036 and 77.4% vs. 97.7%, P=0.007).

CONCLUSIONS

Our results show that ESMR-L and ESD might be superior to conventional EMR for the treatment of small rectal carcinoid tumors.

Comparison of endoscopic resection therapies for rectal carcinoid tumor: endoscopic submucosal dissection versus endoscopic mucosal resection using band ligation

BACKGROUND

Endoscopic mucosal resection (EMR) has been the endoscopic treatment of choice for rectal carcinoid tumors <10 mm in size. Endoscopic submucosal dissection (ESD) may cause more severe complications, longer operation time, and higher cost than EMR.

AIM

: To compare EMR using band ligation (EMR-B) method with ESD for the endoscopic treatment of rectal carcinoid tumors.

METHODS

From November 2008 to September 2011, we enrolled consecutive patients with rectal carcinoid tumors <10 mm in diameter and without lymph node enlargement. Rate of complete resection rate, incidence of complications, and length of procedures were evaluated.

RESULTS

Sixty patients were enrolled (31 ESD cases and 29 EMR-B cases). The mean age was 48.03±13.09 years. Both groups had similar mean tumor diameter (EMR-B 4.34±1.75 vs. ESD 5.22±2.09 mm; P=0.084). Resection time was longer in the ESD group than in the EMR-B group (15.09±5.73 vs. 6.37±5.52 min; P<0.001). The complete resection rate was 80.6% (25 of 31) in the ESD group and 82.8% (24 of 29) in the EMR-B group (P=0.833). In incomplete resection cases, neither local recurrence nor distant metastasis was detected during the follow-up period.

CONCLUSIONS

Compared with ESD, EMR-B resulted in a comparable histologically complete resection rate and took less time to perform. Given the advantages of easier and shorter procedure time, EMR-B may be considered the treatment of choice for small rectal carcinoid tumors.

Factors associated with complete local excision of small rectal carcinoid tumor

PURPOSE

Although small rectal carcinoid tumors can be treated using local excision, complete resection can be difficult because tumors are located in the submucosal layer. We evaluate the factors associated with pathologically complete local resection of rectal carcinoid tumors.

METHODS

Data were analyzed of 161 patients with 166 rectal carcinoid tumors who underwent local excision with curative intent from January 2001 to December 2010. A pathologically complete resection (P-CR) was defined as an en bloc resection with tumor-free lateral and deep margins. The study classified treatments into three categories for analysis: conventional polypectomy (including strip biopsy, snare polypectomy, and hot biopsy), advanced endoscopic techniques (including endoscopic mucosal resection with cap and endoscopic submucosal dissection), and surgical local excision (including transanal excision and transanal endoscopic microsurgery). We evaluated the P-CR rate according to treatment method, tumor size, initial endoscopic impression and the use of endoscopic ultrasound (EUS) or transrectal ultrasound (TRUS).

RESULTS

The mean tumor size was 5.51 ± 2.43 mm (range 2-18 mm) and all lesions were confined to the submucosal layer. The P-CR rates were 30.9, 72.0, and 81.8 % for conventional polypectomy, advanced endoscopic techniques, and surgical local excision, respectively. Univariate analysis showed that P-CR was associated with treatment method, use of EUS or TRUS, and initial endoscopic impression. Multivariate analysis showed that only treatment method was associated with P-CR.

CONCLUSION

Pathologically complete resection of small rectal carcinoid tumors was more likely to be achieved when using advanced endoscopic techniques or surgical local excision rather than conventional polypectomy.

Endoscopic mucosal resection with a ligation device or endoscopic submucosal dissection for rectal carcinoid tumors: an analysis of 24 consecutive cases

AIMS

Endoscopic submucosal dissection (ESD) has several advantages over conventional endoscopic mucosal resection, including a higher en bloc resection rate and more accurate pathological estimation. However, ESD is a complex procedure that requires advanced endoscopic skills. The aim of our study is to evaluate the efficacy of endoscopic mucosal resection with a ligation device (EMR-L) compared to ESD for rectal carcinoid tumors.

METHODS

Between September 2003 and April 2011, 24 rectal carcinoid tumors in 24 patients treated by ESD or EMR-L were retrospectively analyzed. The indications for endoscopic treatment were node-negative rectal carcinoid tumors. We compared the therapeutic outcomes of the ESD group (n = 13) and the EMR-L group (n = 11).

RESULTS

Both groups had similar mean tumor sizes (ESD: 5.5 ± 2.1 mm; EMR-L: 4.4 ± 2.2 mm). The rates of en bloc and complete resection were, respectively, 100% and 92.3% for ESD, and 100% and 100% for EMR-L. Perforations did not occur in either group. Postoperative bleeding occurred in one EMR-L case, and it was endoscopically managed. However, there were no differences in therapeutic outcomes between the two groups. The mean procedure time was longer in the ESD group (28.8 ± 16.2 min) than in the EMR-L group (17.4 ± 4.4 min), without a significant difference. The mean hospitalization period was significantly shorter in the EMR-L group (1.8 ± 3.1 day) than in the ESD group (6.2 ± 2.1 day), and eight EMR-L cases were treated in an outpatient setting.

CONCLUSIONS

EMR-L is a simple and effective procedure that compares favorably to ESD for small rectal carcinoid tumors.

Usefulness of endoscopic submucosal dissection for the treatment of rectal carcinoid tumors

BACKGROUND AND AIM

Various techniques of endoscopy have been developed to treat rectal carcinoids. This retrospective study aimed to evaluate the feasibility and efficacy of endoscopic submucosal dissection for the treatment of rectal carcinoids smaller than 10 mm in diameter.

PATIENTS AND METHODS

A total of 18 consecutive patients were enrolled with 20 carcinoid tumors that had the following characteristics: the diagnosis of a rectal carcinoid smaller than 10 mm, no endoscopic evidence of muscularis propria invasion, and no evidence of lymph node or distant metastasis (11 men and seven women; median age, 69 years; median tumor size, 4 mm). Tumors were resected by endoscopic submucosal dissection with a needle knife and a hook knife. After marking, a one-third to one-half circumferential mucosal incision was made, and subsequently, the submucosa under the lesion was exfoliated. After the submucosa under the tumor was exfoliated, the residual mucosa was incised and the tumor was removed. Complete resection, complication rates, and operation time were evaluated.

RESULTS

Complete resection was achieved in all cases (100%) without complications. The mean operation time was 34.2 min, which was acceptable in clinical practice.

CONCLUSION

Endoscopic submucosal dissection with the strategy described above is feasible and efficacious for selected patients with a rectal carcinoid smaller than 10 mm.

Endoscopic resection for rectal carcinoid tumors: comparison of polypectomy and endoscopic submucosal resection with band ligation

Background/Aims

Rectal carcinoid tumors, at diagnosis, are as small as 10 mm or less in about 80% of patients. These tumors are generally removed by endoscopic resection. The aim of this study was to compare treatment efficacy and safety between endoscopic submucosal resection with band ligation (ESMR-L) and conventional polypectomy.

Methods

Between January 2005 and September 2010, a total of 88 patients, who visited at Busan Paik Hospital and Kosin University Gospel Hospital for endoscopic resection of rectal carcinoid, were reviewed, retrospectively.

Results

Thirty-three cases were treated by ESMR-L, and 55 cases by conventional polypectomy. There were no significant difference in the size of tumor between ESMR-L group and polypectomy group (6.02±2.36 vs. 6.49±3.24 mm, p=0.474). The rate of positive resection margin was significantly lower in ESMR-L group (2/33, 6.1%) than in polypectomy group (19/55, 34.5%; p=0.002). The rate of positive vertical resection margin, among others, was markedly lower in ESMR-L group (1/33, 3.0%) compared to polypectomy group (19/55, 34.5%; p<0.001).

Conclusions

ESMR-L, rather than conventional polypectomy, is a useful treatment option for removal of rectal carcinoid tumors less than 10 mm in diameter.

Endoscopic submucosal dissection (ESD) for gastrointestinal carcinoid tumors

BACKGROUND

Gastrointestinal (GI) carcinoid tumors less than 10 mm in diameter and limited to the submucosal layer demonstrate a low frequency of lymph node and distant metastasis; endoscopic submucosal dissection (ESD) has been used to treat these tumors. However, the number of reported sample cases of rectal carcinoid tumors treated with ESD remains insufficient, and the safety and efficacy of ESD for gastric and duodenal carcinoid tumors have not been elucidated to date.

METHODS

From January 2004 to March 2011, a series of 42 gastrointestinal carcinoid tumors (37 rectal, 2 gastric, and 3 duodenal) in 41 consecutive patients were treated with ESD. Therapeutic efficacy, complications, and follow-up results were retrospectively evaluated.

RESULTS

Sessile type (type Is) was the most prevalent lesion. Mean procedural time was 41 ± 20 min. The mean sizes of tumors and resected specimens were 5 ± 3 mm and 19 ± 7, respectively. The overall rate of en bloc resection was 100% (42/42). Postoperative bleeding occurred in two rectal cases (5%), which were successfully managed with endoscopic clipping. Perforation occurred in two duodenal cases, which could be conservatively managed with medical treatment after endoscopic clipping, and neither laparoscopy nor emergent surgery was needed. No recurrence was observed during the mean follow-up period of 37 months.

CONCLUSIONS

ESD was a safe and effective endoscopic treatment for rectal and gastric carcinoid tumors, although other treatment modalities were desirable for duodenal carcinoid tumors.

Endoscopic submucosal dissection for rectal neuroendocrine (carcinoid) tumors

PURPOSE

Rectal neuroendocrine (carcinoid) tumors smaller than 1 cm without lymph node metastasis and confined within the submucosal layer (stage T1aN0) can be treated using endoscopic resection. The present study was aimed to assess the safety and efficacy of endoscopic submucosal dissection (ESD) for T1aN0 carcinoid tumors.

PATIENTS AND METHODS

A total of 35 consecutive patients with a T1aN0 rectal carcinoid tumor were enrolled between March 2007 and December 2009. The study evaluated the histologically complete resection rate, procedure time, complications, and short-term oncological outcomes.

RESULTS

The mean patient age was 49.0 years (range, 32-74 years), and there were 25 men and 10 women. The mean procedure time was 35.6 minutes (range, 7-82 minutes). All neoplasms were removed in one piece, and the histologically complete resection rate was 74.3% (26 cases including 5 cases showing no residual tumor). No post-ESD bleeding was observed. Abdominal computed tomography scans showed a perforation in 1 patient only, but that perforation was not associated with any peritonitis symptoms, and the patient was discharged on postprocedure day 3. One patient underwent radical surgery after ESD because of angiolymphatic invasion and positive resection margins, and the final pathology revealed no residual tumor or lymph node metastasis. No patient showed local recurrence or distant metastasis during a median follow-up of 25 months (range, 12-43 months).

CONCLUSIONS

ESD is feasible and safe for treating T1aN0 rectal carcinoid tumors. Further studies are required to accurately determine long-term oncological outcomes.

Feasibility of salvage endoscopic mucosal resection by using a cap for remnant rectal carcinoids after primary EMR

BACKGROUND

Secondary endoscopic treatment for remnant lesions of rectal carcinoid tumors after primary EMR or polypectomy is technically difficult because of fibrosis of residual tissues. EMR by using a cap (EMR-C), a method to resect the submucosal layer by suction by using a transparent cap, may be feasible as a salvage treatment.

OBJECTIVE

To assess the feasibility of salvage EMR-C.

DESIGN

Retrospective analysis.

SETTING

Tertiary academic health care system.

PATIENTS

Thirty-one patients who were referred for salvage treatment of a failed en bloc excision of rectal carcinoid tumors after primary EMR or polypectomy between January 2007 and December 2009.

INTERVENTIONS

Salvage EMR-C for remnant carcinoid tumors in the rectum.

MAIN OUTCOME MEASUREMENTS

Rate of complete resection, complications, length of procedure, and recurrence rate.

RESULTS

The mean age of the patients was 52.0±11.8 years (range 30-78 years). The mean tumor size was 8.9±3.2 mm (range 5.0-13.0 mm). The mean procedure time was 9.1±3.7 minutes, and clear resection margins were pathologically confirmed in all 31 patients. The most common complication of salvage EMR-C was bleeding (7 patients, 22.6%), which was successfully treated by hemoclipping in all cases. The 1-year follow-up colonoscopy and CT results for all patients were negative for recurrence.

LIMITATIONS

Retrospective design and limited cases at a single center.

CONCLUSIONS

EMR-C is a feasible salvage therapeutic option for failed en bloc excision after primary endoscopic treatment of rectal carcinoid tumors.

Endoscopic submucosal dissection for treatment of rectal carcinoid tumors

BACKGROUND

Conventional EMR has been the endoscopic treatment of choice for rectal carcinoid tumors. However, histologically complete resection often cannot be achieved because the carcinoid tumors are located mainly in the submucosal layer. Endoscopic submucosal dissection (ESD), a new method for large colorectal neoplasm resection, may overcome this problem.

OBJECTIVE

To compare ESD with EMR for the endoscopic treatment of rectal carcinoid tumors.

DESIGN

A prospective case series with comparison to retrospective controls.

SETTING

Tertiary-care center.

PATIENTS

From January 2007 to January 2009 we prospectively enrolled consecutive patients with rectal carcinoid tumors less than 16 mm in diameter and with no regional lymph node enlargement shown by CT or EUS. For comparison, we retrospectively randomly selected patients who had undergone EMR for treatment of rectal carcinoid tumors between March 2000 and December 2006.

INTERVENTION

We performed ESD of rectal carcinoid tumors in prospectively enrolled patients.

MAIN OUTCOME MEASUREMENTS

Rate of en bloc resection, rate of histologically complete resection, incidence of complications, and length of procedures.

RESULTS

The ESD group contained 31 patients (18 male, 13 female; age range 34-65 years), and the EMR group contained 62 patients (42 male, 20 female; age range 22-77 years). Both groups had similar mean rectal carcinoid tumor diameters (ESD 6.8 +/- 2.4 mm, EMR 7.3 +/- 2.2 mm; P = .106). Resection time was longer in the ESD group than in the EMR group (11.4 +/- 3.7 minutes vs 4.2 +/- 3.2 minutes, P < .001). The en bloc resection rate was 100% (31 of 31) in the ESD group and 95.2% (59 of 62) in the EMR group (P = .213). The histologically complete resection rate was 90.3% (28 of 31) in the ESD group and 71.0% (44 of 62) in the EMR group (P = .035). Suspected perforation occurred in 1 ESD patient (3.2%) and in 1 EMR patient (1.6%), and both patients were successfully managed by conservative measures. Immediate bleeding occurred in 1 ESD patient (3.2%) and in 4 EMR patients (6.5%); all instances of bleeding were controlled endoscopically.

LIMITATIONS

Retrospective control study and limited experience at a single center.

CONCLUSION

Compared with EMR, ESD resulted in a higher histologically complete resection rate, had a similar complication rate, and took slightly longer to perform. Given the advantages of complete resection, these findings indicate that ESD may be considered for treatment of rectal carcinoid tumors.

Endoscopic submucosal dissection and preoperative assessment with endoscopic ultrasonography for the treatment of rectal carcinoid tumors

BACKGROUND

Rectal carcinoid tumors 10 mm in diameter or smaller located within the submucosal layer can be cured by local excision including endoscopic treatment. But complete resection of these tumors with endoscopic polypectomy is difficult. This study aimed to evaluate the usefulness of endoscopic submucosal dissection (ESD) and endoscopic ultrasonography (EUS) for the treatment of rectal carcinoid tumors.

METHODS

In this study, 22 rectal carcinoid tumors in 21 patients were evaluated with EUS and treated using ESD from January 2004 to December 2008.

RESULTS

The mean size of the resected tumors was 6.1 mm (range, 2.0-10 mm) on histopathologic evaluations. When the sizes of the tumors shown by EUS and histopathologic evaluation were compared, the mean values were not significantly different. All the tumors were located within the submucosal layer, and the accuracy of the preoperative depth determination with EUS was 100% (22/22). The mean duration of the ESD procedure was 37 min (range, 20-71 min). The overall rate of en bloc resection with ESD was 100% (22/22). Although postoperative bleeding occurred in two cases (9%), both cases were successfully managed by endoscopic hemostasis. No perforation or recurrence was observed during the mean follow-up period of 30 months (range, 7-66 months).

CONCLUSIONS

Endoscopic submucosal dissection and preoperative assessment with EUS are effective for treating rectal carcinoid tumors and enabling en bloc resection.

Endoscopic submucosal dissection for colorectal neoplasms

Although endoscopic submucosal dissection (ESD) gains acceptance as one of the standard treatments for esophageal and stomach neoplasms in Japan, it is still in the developing stage for colorectal neoplasms. In terms of indications, little likelihood of nodal metastasis and technical resectability are principally considered. Some of intramucosal neoplasms, carcinomas with minute submucosal invasion, and carcinoid tumors, which are technically unresectable by conventional endoscopic treatments, may become good candidates for ESD, considering substantial risks and obtained benefits. ESD as a staging measure to obtain histological information of the invasion depth and lymphovascular infiltration is acceptable because preoperative prediction is difficult in some cases. In terms of techniques, advantages of ESD in comparison with other endoscopic treatments are to be controllable in size and shape, and to be resectable even in large and fibrotic neoplasms. The disadvantages may be longer procedure time, heavier bleeding, and higher possibility of perforation. However, owing to refinement of the techniques, invention of devices, and the learning curve, acceptable technical safety has been achieved. Colorectal ESD is very promising and become one of the standard treatments for colorectal neoplasms in the near future.

Endoscopic submucosal dissection for rectal carcinoid tumors

BACKGROUND

Endoscopic submucosal dissection (ESD) has an advantage over endoscopic mucosa resection (EMR) by enabling removal of gastrointestinal neoplasms en bloc. The ESD procedure is the treatment of choice for rectal carcinoids that have classic histologic architecture with minimal cellular pleomorphism and sparse mitoses, but it has not been applied for such tumors.

METHODS

The ESD procedure was performed for patients with colorectal tumors that fulfilled the inclusion criteria specifying tumor with a diameter of 10 mm or less, no muscular layer invasion, and no metastases to the lymph nodes or distal organs. The ESD procedure was performed for patients with rectal carcinoids but no node or distal metastasis.

RESULTS

This study enrolled 20 rectal carcinoid tumors from 20 consecutive patients. The mean tumor size was 7.6 mm (range, 3-16 mm). En bloc removal was achieved for all the tumors, and the complete resection (en bloc with tumor-free lateral/basal margins) rate was 90% (18/20). The two cases in which the margins were not evaluable due to burn effects still are free of recurrence and metastasis at this writing. Perforation was seen in one case, which was managed nonsurgically.

CONCLUSIONS

Precise histolopathogic assessment of the specimens resected en bloc by ESD may reduce tumor recurrence and metastasis after ESD. As the treatment of choice for small rectal carcinoids, ESD is associated with nominal risks of metastatic disease.

Selection of cap size in endoscopic submucosal resection with cap aspiration for rectal carcinoid tumors

BACKGROUND

Small rectal carcinoid tumors (<or=1 cm in diameter) can be treated by endoscopic resection, but complete resection may be difficult if tumors are located in the deep submucosal layer. This study was performed to identify the clinicopathologic factors affecting the complete resection of small rectal carcinoid tumors, using the endoscopic submucosal resection with cap aspiration technique (ESMR-C).

MATERIALS AND METHODS

Forty-one consecutive patients with 42 rectal carcinoid tumors who underwent ESMR-C from October 2003 to November 2006 were assessed. Complete resection was defined as a clean margin that was free of tumor invasion at the lateral and inferior edges.

RESULTS

The rate of complete tumor removal by ESMR-C was 85.7% and no complications occurred. The tumor size, location, and method of resection did not significantly affect the completeness of resection. Univariate analysis showed that the rate of complete resection was significantly higher when using 19.2-mm, compared with 13.9-mm, caps (96.0 vs. 70.6%; P = 0.032). Multivariate analysis showed that the cap size was an independent factor predicting the completeness of resection.

CONCLUSION

The use of large-sized caps increases the completeness of the resection of rectal carcinoid tumors when using ESMR-C.

Perspective on the practical indications of endoscopic submucosal dissection of gastrointestinal neoplasms

Endoscopic submucosal dissection (ESD) is a new endoluminal therapeutic technique involving the use of cutting devices to permit a larger resection of the tissue over the muscularis propria. The major advantages of the technique in comparison with polypectomy and endoscopic mucosal resection are controllable resection size and shape and en bloc resection of a large lesion or a lesion with ulcerative findings. This technique is applied for the endoscopic treatment of epithelial neoplasms in the gastrointestinal tract from the pharynx to the rectum. Furthermore, some carcinoids and submucosal tumors in the gastrointestinal tract are treated by ESD. To determine the indication, two aspects should be considered. The first is a little likelihood of lymph node metastasis and the second is the technical resectability. In this review, practical guidelines of ESD for the gastrointestinal neoplasms are discussed based on the evidence found in the literature.

Successful outcomes of EMR-L with 3D-EUS for rectal carcinoids compared with historical controls

AIM: To assess the results of endoscopic mucosal resection with a ligation device (EMR-L) combined with three dimensional endoscopic ultrasonography (3D-EUS) using an ultrasonic probe for rectal carcinoids. In addition, diagnosis of the depth and size of lesions by EUS was evaluated.

METHODS: Between January 2003 and March 2007, 20 patients underwent EMR-L with 3D-EUS using an ultrasonic probe (group A). 3D-EUS was combined with EMR-L at the time of injection of sterile physiological saline into the submucosal layer. For comparison, 14 rectal carcinoids that had been treated by EMR-L without 3D-EUS between April 1998 and December 2002 were evaluated as historical controls (group B). EUS was conducted for all of the patients before treatment to evaluate tumor diameter and depth of invasion. The percentage of complete resection and the vertical resection margin were compared between the two groups.

RESULTS: The depth of invasion upon histopathological examination was in complete agreement with the pre-operative findings by EUS. The tumor diameter determined by EUS approximated that found in the tissue samples. There were no significant differences in the gender, tumor sites or tumor diameters between the two groups. The rate of complete resection for groups A and B was 100% and 71%, respectively (P < 0.05). The vertical resection margin of group A was longer than that of group B.

CONCLUSION: EMR-L is effective as an endoscopic treatment for rectal carcinoids. In combination with 3D-EUS, safe and complete resection is further assured.

Submucosal cushioning with water jet before endoscopic mucosal resection : Which fluids are effective?

BACKGROUND

Several new techniques have recently been described that allow the endoscopic mucosal resection even of broad-based flat lesions in the gastrointestinal tract. The technique recently described by us of using a water jet dissector (Helix HydroJet) for a selective deposition of liquid in the submucosal lamina has now been combined with different substances, and their effects have been compared.

MATERIAL AND METHODS

Gastroscopies were carried out in 8 pigs under intubation anesthesia, and 2 submucosal cushions each were created in the stomach using one out of 4 test substances (gelatin, glucose 50, hydroxyethyl starch [HES] 10%, dextran 40), as well as one cushion of isotonic saline solution placed in each area via the Helix HydroJet). The height of the submucosal cushions was intermittently measured over a period of 40 or 20 min, respectively, by miniprobe endosonography. In 7 of the animals the stomach was subsequently subjected to mucosal resection. The specimens and the gastric wall were histologically assessed to evaluate the localization of the liquid cushion and the effect on adjacent layers of the gastric wall.

RESULTS

All test substances produced strictly selective liquid cushions in the submucosa. With HES 10% and dextran the maximum height of the cushions initially increased and then decreased during the further course to an average of 90% of the initial height within 40 min. Isotonic saline solution showed the most rapid decrease in height (72% after 20 min). The histological assessment confirmed the selective nature of the liquid deposit in the submucosa.

DISCUSSION

Plasma expanders produced cushions that initially increased in height but then remained constant for a longer period than cushions produced using glucose 50, gelatin, or isotonic saline solution. The combination of transmucosal jet application for elevation of the mucosa with plasma expanders is therefore an interesting approach to optimize endoscopic mucosal resections.

Endoscopic submucosal resection with a ligation device is an effective and safe treatment for carcinoid tumors in the lower rectum

BACKGROUND AND AIMS

Various methods for complete endoscopic resection of rectal carcinoid tumors have been reported; however, the number of cases investigated in each study has been limited. The aim of the present study was to clarify the clinical usefulness of a novel technique named endoscopic submucosal resection with a ligation device (ESMR-L) in a large number of rectal carcinoid tumors.

PATIENTS AND METHODS

Between January 1999 and March 2005, a total of 61 patients with 63 rectal carcinoid tumors estimated at 10 mm or less in diameter, without atypical features and resected by ESMR-L were recruited for this analysis. The complete resection rate, complications associated with the procedure, local recurrence, and distant metastases were evaluated.

RESULTS

Sixty-one patients were 36 males and 25 females with a mean age of 59 +/- 11 years (24-76 years). Tumor size ranged from 2 to 12 mm in diameter, with an average size of 6.4 +/- 2.4 mm. Fifty-nine lesions (93.6%) were located in the lower rectum (Rb), three in the upper rectum (Ra) and one in the recto-sigmoid colon (Rs). In total, 60 out of 63 lesions (95.2%) were histologically determined to be completely resected. The complete resection rate for lesions located in the Rb was 98.3%, which was significantly higher than that for lesions in Ra and Rs (50%). Minor bleeding associated with the procedure occurred in five lesions (7.9%), but all cases were successfully managed with hemoclips. Histopathologically, all tumors were located in the submucosal layer, and all were classified as classical-type carcinoids without lymphovascular invasion. Neither local recurrence nor distant metastasis was detected during a median follow-up period of 24 months.

CONCLUSION

In a large number of cases, ESMR-L proved to be a useful and safe procedure to resect rectal carcinoid tumors 10 mm or less in diameter, especially for those located in the Rb.

Selective fluid cushion in the submucosal layer by water jet: advantage for endoscopic mucosal resection

BACKGROUND/AIM

Numerous new techniques have recently been reported and described for the endoscopic mucosal resection of large superficial lesions of the gastrointestinal tract. We present here for the first time the application of a water jet dissector for mucosa elevation.

MATERIALS AND METHODS

In an ex vivo study, the effectiveness of a water jet dissector (Helix Hydro-Jet) placed directly on the stomach walls of 8 pigs was examined to create a mucosal elevation. After having determined optimal pressures, angle of application, and application times, 13 submucosal fluid cushions were produced in different areas of the stomach walls of 8 pigs in vivo, and the sizes of the resulting submucosal cushions were measured.

RESULTS

Using pressures between 30 and 70 bar, it was routinely possible to create submucosal fluid cushions in the stomach wall ex vivo as well as in vivo. Histological examination showed a selective edema in the submucosa without damage to the deeper mucosal layers of the gastric wall.

CONCLUSIONS

The capacity of a targeted high-pressure water jet to penetrate the mucosa and selectively create a fluid cushion in the submucosa facilitates endoscopic resection of the mucosa. This new method could contribute to ameliorate the endoscopic treatment of mucosal tumors which previously could not be resected endoscopically due to their size, extent, or location.

Rectal carcinoids

PURPOSE OF REVIEW

To provide an updated review of the diagnosis, management, and treatment of rectal carcinoid tumors, with special emphasis on minimally invasive surgical techniques to treat localized disease.

RECENT FINDINGS

Carcinoids are morphologically and biologically heterogeneous neuroendocrine tumors that have malignant potential, and are most commonly found in the gastrointestinal tract. The incidence of all carcinoids appears to be increasing, which may reflect improved diagnostic modalities. The rectum is the third most common location for gastrointestinal carcinoids. Recent data have suggested that rectal carcinoids are over-represented in Black and Asian populations. The survival rate for patients with rectal carcinoids is superior to that of carcinoids found elsewhere in the gastrointestinal tract. Tumor size in rectal carcinoids is predictive of metastasis and can reliably guide management. Review of recent literature demonstrates good evidence that localized rectal carcinoids are amenable to local resection.

SUMMARY

With widespread colorectal cancer screening, heightened awareness, and improved diagnostic modalities, the incidence of rectal carcinoids should continue to increase. There is evidence that convincingly demonstrates that patients with rectal carcinoids less than 2 cm in diameter, localized to the mucosa or submucosa, may be safely and effectively removed via minimally invasive resection.

Yield of tissue sampling for subepithelial lesions evaluated by EUS: a comparison between forceps biopsies and endoscopic submucosal resection

BACKGROUND

In most circumstances, subepithelial tumors lack distinct endoscopic and ultrasonographic features. Consequently, definitive diagnosis usually requires tissue acquisition and pathologic confirmation. Establishing a tissue diagnosis is difficult because the yield of forceps biopsies is low. However, prospective data evaluating tissue sampling techniques for subepithelial lesions are currently lacking.

OBJECTIVE

Our purpose was to prospectively determine the diagnostic yield of endoscopic submucosal-mucosal resection (ESMR) compared with forceps biopsy for lesions limited to the submucosa (third endosonographic layer) of the GI tract.

DESIGN

A prospective head-to-head comparison was performed.

SETTING

The study was performed in a tertiary care hospital.

PATIENTS

Study patients were 23 adults with subepithelial lesions limited to the submucosa.

INTERVENTION

All submucosal lesions underwent forceps biopsy followed by endoscopic submucosal resection. Biopsy specimens were obtained with large-capacity "jumbo" forceps. A total of 4 double passes (8 biopsy specimens) were collected from each lesion with use of the bite-on-bite technique. Endoscopic resection was then performed with an electrosurgical snare or cap-fitted endoscopic mucosal resection device.

MAIN OUTCOME MEASUREMENT

The main outcome measurement was the diagnostic yield of biopsy forceps compared with endoscopic submucosal resection.

RESULTS

Twenty-three patients with lesions limited to the submucosa were identified by endoscopic ultrasonography. All lesions underwent forceps biopsy followed by ESMR. The diagnostic yield of the jumbo forceps biopsy was 4 of 23 (17%), whereas the diagnostic yield of ESMR was 20 of 23 (87%) (P = .0001, McNemar test).

CONCLUSION

In the evaluation of subepithelial lesions limited to the submucosa, ESMR has a significantly higher diagnostic yield than jumbo forceps biopsy with use of the bite-on-bite technique.