Endoscopic resection for duodenal carcinoid tumors: a multicenter, retrospective study

Long-term outcomes of endoscopic resection for well-differentiated nonampullary duodenal neuroendocrine tumors

BACKGROUND AND AIMS

Nonampullary duodenal neuroendocrine tumors (NAD-NETs) are rare, with limited evidence regarding endoscopic treatment. This study investigated the efficacy and safety of endoscopic resection of well-differentiated NAD-NETs and evaluated long-term outcomes, including local recurrence and metastasis.

METHODS

Seventy-eight patients with NAD-NETs who underwent endoscopic resection between January 2011 and August 2022 were included. Clinicopathologic characteristics and treatment outcomes were collected and analyzed.

RESULTS

En-bloc resection was achieved for 74 tumors (94.9%) and R0 resection for 68 tumors (87.2%). Univariate analysis identified tumors in the second part of the duodenum, tumor size ≥10 mm, and muscularis propria invasion as risk factors for noncurative resection. Two patients with R1 resection (vertical margin involvement) and 2 patients with lymphovascular invasion underwent additional surgery. Four patients experienced adverse events (5.1%), including 2 cases of delayed bleeding and 2 cases of perforation, all successfully managed conservatively. During a median follow-up period of 62.6 months, recurrence and lymph node metastasis were only detected in 1 patient with R1 resection 3 months after the original procedure.

CONCLUSIONS

Endoscopic resection is safe and effective and provides a favorable long-term outcome for patients with well-differentiated NAD-NETs without regional lymph node or distant metastasis.

Factors associated with gastric and duodenal neuroendocrine tumors: A multicenter case-control study

BACKGROUND AND AIMS

The incidence of gastric and duodenal neuroendocrine tumors (GNET and DNET, respectively) is increasing, however associated factors of these diseases are not well known. Here, we investigated the factors associated with GNET and DNET.

METHODS

Patients with GNET and DNET presenting at eight tertiary referral centers between 2001 and 2020 were included and compared with healthy controls who underwent upper endoscopic screening. Clinical factors and laboratory data were analyzed to determine associated factors of GNET and DNET.

RESULTS

Overall, 396 patients with GNET and 193 patients with DNET were included and compared with 1725 healthy controls. Multivariate analysis showed that age (odds ratio [OR] 0.98), diabetes (OR 1.72), hypertension (OR 1.97), low serum high-density lipoprotein cholesterol (HDL-C) levels (OR 2.54), and past/present H. pylori infection (OR 1.46) were significantly associated with GNET. In contrast, DNET was significantly associated with diabetes (OR 1.80), hypertension (OR 1.68), low serum HDL-C levels (OR 2.29), and past/present H. pylori infection (OR 5.42). In the sex-based subgroup analysis in GNET, current smoking was strongly associated in women (OR 9.85), but not in men.

CONCLUSIONS

This study identified several common metabolic factors associated with GNET and DNET. Additionally, some factors had sex-specific associations.

Primary coexisting adenocarcinoma of the colon and neuroendocrine tumor of the duodenum: A case report and review of the literature

BACKGROUND

Neuroendocrine tumors (NETs) arise from the body's diffuse endocrine system. Coexisting primary adenocarcinoma of the colon and NETs of the duodenum (D-NETs) is a rare occurrence in clinical practice. The classification and treatment criteria for D-NETs combined with a second primary cancer have not yet been determined.

CASE SUMMARY

We report the details of a case involving female patient with coexisting primary adenocarcinoma of the colon and a D-NET diagnosed by imaging and surgical specimens. The tumors were treated by surgery and four courses of chemotherapy. The patient achieved a favorable clinical prognosis.

CONCLUSION

Coexisting primary adenocarcinoma of the colon and D-NET were diagnosed by imaging, laboratory indicators, and surgical specimens. Surgical resection combined with chemotherapy was a safe, clinically effective, and cost-effective treatment.

Endoscopic resection for non-ampullary duodenal subepithelial lesions: a retrospective cohort study

PURPOSE

This study aimed to assess the safety and efficacy of endoscopic submucosal dissection (ESD) and pre-cutting endoscopic mucosal resection (pEMR) in treating non-ampullary duodenal subepithelial lesions (NADSELs) and to evaluate the clinical utility of endoscopic ultrasound (EUS) before endoscopic resection (ER).

METHODS

In this retrospective single-centre cohort study, we compared the clinical outcomes of patients with NADSELs who underwent ESD or pEMR between January 2014 and June 2023. The accuracies of EUS in determining the pathological type and origin of the lesions were evaluated using postoperative histopathology as the gold standard.

RESULTS

Overall, 56 patients with NADSELs underwent ER in this study, including 16 and 40 treated with pEMR and ESD, respectively. There were no significant differences between the two groups in terms of en bloc resection rate, complete (R0) resection rate, perioperative complication rate, and postoperative hospital length of stay (P > 0.05). However, the pEMR group had significantly shorter median operational (13.0 min vs. 30.5 min, P < 0.001) and mean fasting (1.9 days vs. 2.8 days, P = 0.006) time and lower median hospital costs (¥12,388 vs. ¥19,579, P = 0.002). The accuracies of EUS in determining the pathological type and origin of the lesions were 76.8% and 94.6%, respectively, compared with histopathological evaluation.

CONCLUSIONS

EUS can accurately predict the origin of NADSELs. Suitable lesions determined to originate from the submucosa or more superficial layers using EUS can be treated using pEMR as it shortens the operational and recovery time, reduces hospitalisation costs, and achieves an R0 resection rate similar to ESD.

Survival of patients managed in France for duodenal neuroendocrine tumors (D-NET): a 20-year multicenter cohort study from the GTE group: a cohort study

INTRODUCTION

Duodenal neuroendocrine tumours (D-NETs) have a low incidence; however, their diagnosis has been increasing. Features such as tumour location, size, type, histological grade, and stage were used to adapt the treatment to either endoscopic (ER) or surgical (SR) resections. There is no consensus regarding the definitive treatment. The authors' study aimed to describe the management of non-metastatic, well-differentiated D-NETs in France and its impact on patient survival.

METHODS

A registry-based multicenter study using prospectively collected data between 2000 and 2019, including all patients managed for non-metastatic G1 and G2 D-NETs, was conducted in the GTE group.

RESULTS

A total of 153 patients were included. Fifty-eight benefited from an ER, and 95 had an SR. No difference in recurrence-free survival (RFS) was observed regardless of treatment type. There was no significant difference between the two groups (ER vs. SR) in terms of location, size, grade, or lymphadenopathy, regardless of the type of incomplete resection performed or regarding the pre-therapeutic assessment of lymph node invasion in imaging. The surgery allowed for significantly more complete resection (patients with R1 resection in the SR group: 9 vs. 14 in the ER group, P <0.001). Among the 51 patients with positive lymph node dissection after SR, tumour size was less than or equal to 1 cm in 25 cases. Surgical complications were more numerous ( P =0.001). In the sub-group analysis of G1-G2 D-NETs between 11 and 19 mm, there was no significant difference in grade ( P =0.977) and location ( P =0.617) between the two groups (ER vs. SR). No significant difference was found in both morphological and functional imaging, focusing on the pre-therapeutic assessment of lymph node invasion ( P =0.387).

CONCLUSION

Regardless of the resection type (ER or SR) of G1-G2 non-metastatic D-NETs, as well as the type of management of incomplete resection, which was greater in the ER group, long-term survival results were similar between ER and SR. Organ preservation seems to be the best choice owing to the slow evolution of these tumours.

Endoscopic management of gastric, duodenal and rectal NETs: Position paper from the Italian Association for Neuroendocrine Tumors (Itanet), Italian Society of Gastroenterology (SIGE), Italian Society of Digestive Endoscopy (SIED)

The present paper reflects the position of the Italian Association for Neuroendocrine Tumors (Itanet), the Italian Society of Gastroenterology (SIGE), and the Italian Society of Digestive Endoscopy (SIED) regarding the management of patients affected by gastric, duodenal, and rectal neuroendocrine neoplasms (NENs) amenable to endoscopic treatment. The key questions discussed in this paper are summarized in Table 1. Data were extracted from the MEDLINE database through searches; expert opinions and recommendations are provided in accordance with the available scientific evidence and the authors' expertise. Recommendations are presented alongside a level of evidence and grade of recommendation based on the GRADE system. This paper specifically focuses on subgroups of NENs considered suitable for endoscopic management according to current international guidelines: i. well-differentiated gastric neuroendocrine tumors (gNET) type 1 < 2 cm and selected cases of type 3; ii. well-differentiated duodenal, non-functioning, non-ampullary NET with size < 2 cm; and well-differentiated rectal NET with size < 2 cm.

Endoscopic Resection for Duodenal Neuroendocrine Neoplasms between 10 and 20 mm-A Systematic Review and Meta-Analysis

Background. The optimal management of duodenal neuroendocrine neoplasms (dNENs) sized 10-20 mm remains controversial and although endoscopic resection is increasingly performed instead of surgery, the therapeutic approach in this setting is not fully standardized. We performed a systematic review of the literature and a meta-analysis to clarify the outcomes of endoscopic resection for 10-20 mm dNENs in terms of efficacy (i.e., recurrence rate) and safety. Methods. A computerized literature search was performed using relevant keywords to identify pertinent articles published until January 2023. Results. Seven retrospective studies were included in this systematic review. The overall recurrence rate was 14.6% (95%CI 5.4-27.4) in 65 patients analyzed, without significant heterogeneity. When considering studies specifically focused on endoscopic mucosal resection, the recurrence rate was 20.5% (95%CI 10.7-32.4), without significant heterogeneity. The ability to obtain the free margin after endoscopic resection ranged between 36% and 100%. No complications were observed in the four studies reporting this information. Conclusions. Endoscopic resection could be the first treatment option in patients with dNENs sized 10-20 mm and without evidence of metastatic disease. Further studies are needed to draw more solid conclusions, particularly in terms of superiority among the available endoscopic techniques.

Duodenal neuroendocrine tumors: Short-term outcomes of endoscopic submucosal dissection performed in the Western setting

Background and study aims Endoscopic resection (ER) is recommended for the management of duodenal neuroendocrine tumors (D-NETs) confined to the submucosal layer, without lymph node or distant metastasis. While this is accepted practice for lesions < 10 mm, consensus for larger lesions remains unclear. Although endoscopic submucosal dissection (ESD) has been proposed as the preferred ER technique for DNETs ≥10 mm, there are limited data on efficacy and safety, particularly in the Western setting. Patients and methods We performed a retrospective analysis of patients with D-NETs who underwent ESD between 2012 and 2022 in three tertiary referral centers in Australia, France, and Belgium. Results Fourteen patients with 15 D-NETs were evaluated. Median patient age was 64 years (interquartile range [IQR] 58-70 years). All D-NETs were confined to the duodenal bulb. Median D-NET size was 10 mm (IQR 7-12 mm) and specimen size was 15 mm (IQR 15-20 mm). Median procedure time was 60 minutes (IQR 25-90 minutes). The rate of en bloc resection was 100%. Intra-procedural perforation occurred in four patients (26.7%), with all closed endoscopically without long-term sequelae. There were no episodes of clinically significant bleeding. No local recurrence, lymph node or distant metastasis was observed at a median follow-up of 19.9 months (IQR 10.3-49.3 months). Conclusions In experienced hands, ESD for D-NETs can achieve a 100% en bloc resection rate. There were no cases of local recurrence or distant metastatic spread, indicating that ESD may be a viable option for patients with D-NETs 10 to 15 mm that are not surgical candidates.

Surgical and Endoscopic Resection of Duodenal Neuroendocrine Tumors Have Similar Disease-Specific Survival Outcome

BACKGROUND

Duodenal neuroendocrine tumors (dNETs) are rare, and their management is not well-defined. National Comprehensive Cancer Network (NCCN) guidelines recommend surgical resection of large dNETs (> 2 cm) and endoscopic resection of small tumors (< 2 cm). We compared the survival outcomes between surgical and endoscopic resection in various dNET sizes.

METHODS

A retrospective cohort study was conducted using patient data from Surveillance, Epidemiology, and End Results Program (SEER) database. Variables analyzed included age, tumor size, grade, stage, and lymph node status. Disease-specific survival (DSS) was compared for endoscopic and surgical groups in dNET size strata: 0-0.5, 0.5-1, 1-2, 2-3, and > 3 cm. Kaplan-Meier and multivariable Cox proportional hazards models were used for survival analysis.

RESULTS

The study included 465 patients, with 124 (26.7%) undergoing surgical resection. The average age was 61.9 years, and tumor sizes ranged from 0.1 to 10.5 cm. Endoscopic resection had 40.5% of tumors between 0 and 0.5 cm, while surgery had only 21% (p < 0.001). In the surgical cohort, 79.8% had grade 1 tumors compared to 88.3% in the endoscopy group (P = 0.024). Among surgically resected cases, 48.4% (60 patients) had lymph node involvement. Age, tumor size, grade, and stage did not significantly predict survival after surgical resection. Stratified by tumor size, no difference in DSS was observed between surgery and endoscopy groups.

CONCLUSIONS

Endoscopic resection demonstrated similar survival outcomes to surgical resection across dNET sizes in this national analysis. Given the risks and the lack of survival benefits for surgery, endoscopic resection may be beneficial for both small and large tumors. Further studies are warranted to validate the current NCCN guidelines.

Long-term outcomes of endoscopic resection for duodenal neuroendocrine tumors

Duodenal neuroendocrine tumors (d-NETs) ≤ 10 mm in size, confined to the submucosal layer, without lymph node or distant metastasis, can be treated safely and effectively by endoscopic management. However, most results are based on limited data and short follow-up outcomes. Herein, we aimed to evaluate the short-term and long-term outcomes of endoscopic resection for d-NETs. We retrospectively analyzed 63 patients with 68 d-NETs who had undergone endoscopic resection at two hospitals between January 2009 and December 2021. En-bloc resection, endoscopically complete resection, and histopathologically complete resection rates were evaluated as short-term outcomes. Furthermore, long-term outcomes were analyzed in 46 patients with 50 d-NETs with a follow-up period of > 1 year. The overall en-bloc, endoscopically complete, and histopathologically complete resection rates were 92.6% (63/68), 100% (68/68), and 69.1% (47/68), respectively. Tumor size (> 5 mm) was the only predictive factor for histopathologically incomplete resection (p = 0.015). The procedure-related bleeding and perforation rates were 0% and 5.9%, respectively. No recurrences were observed in patients with histopathologically complete resection and those with histopathologically incomplete resection at a median follow-up period of 48 months (range 12-132 months). Endoscopic resection for d-NETs ≤ 10 mm in size, limited to the submucosal layer, and without lymph node or distant metastasis provides favorable long-term outcomes when endoscopically complete resection is achieved.

The meaning of R1 resection after endoscopic removal of gastric, duodenal and rectal neuroendocrine tumors

INTRODUCTION

Well-differentiated gastric, duodenal, and rectal neuroendocrine neoplasms (NETs) are rare diseases usually managed by endoscopic treatment. Although several endoscopic techniques are available, the number of patients with incomplete (R1) resection is significant.

AREAS COVERED

This review focuses on the meaning of incomplete R1 findings after endoscopic resection in type I gastric NETs; nonfunctioning, non-ampullary duodenal NETs; and small rectal NETs. Data were identified by MEDLINE database search without publication date limitation.

EXPERT OPINION

An incomplete R1 finding may have no significant impact on a patient's clinical outcome, particularly in small G1 type I gastric NETs, which have an indolent course. A 'stepwise approach,' which uses more advanced endoscopic techniques, or minimally invasive surgery may be justified to achieve complete margin-free resection. This approach must balance the tumor features and the procedure-related risk of complications, particularly in the duodenum, where the role of deep endoscopic resections is limited due to the thin duodenal wall. Gastric and rectal NETs that are incompletely removed after initial resection are more easily amenable to deep endoscopic techniques. However, this might not be necessary for patients with comorbidities, elderly, or both due to the uncertainty of how R1 finding impacts a patient's clinical outcome.

Small bowel neuroendocrine tumours - casting the net wide

PURPOSE OF REVIEW

Our aim is to provide an overview of small bowel neuroendocrine tumours (NETs), clinical presentation, diagnosis algorithm and management options. We also highlight the latest evidence on management and suggest areas for future research.

RECENT FINDINGS

Dodecanetetraacetic acid (DOTATATE) scan can detect NETs with an improved sensitivity than when compared with an Octreotide scan. It is complimentary to small bowel endoscopy that provides mucosal views and allows the delineation of small lesions undetectable on imaging. Surgical resection is the best management modality even in metastatic disease. Prognosis can be improved with the administration of somatostatin analogues and Evarolimus as second-line therapies.

SUMMARY

NETs are heterogenous tumours affecting most commonly the distal small bowel as single or multiple lesions. Their secretary behaviour can lead to symptoms, most commonly diarrhoea and weight loss. Metastases to the liver are associated with carcinoid syndrome.

Magnifying Endoscopy with Narrow-Band Imaging for Duodenal Neuroendocrine Tumors

Duodenal neuroendocrine tumors (NETs) are rare subepithelial tumors that arise from the neuroendocrine cells beneath the epithelial layer. However, an accurate histopathological diagnosis is difficult when tissue samples are obtained using conventional endoscopic forceps biopsy alone. This study aimed to evaluate the magnifying endoscopy with narrow-band imaging (ME-NBI) findings of duodenal NETs. We retrospectively analyzed a database of 22 duodenal NETs from 21 patients who underwent ME-NBI between January 2011 and June 2022. The ME-NBI, endosonographic, and histopathologic findings of duodenal NETs were analyzed. Nineteen lesions were located in the bulb, two were located in the superior duodenal angle, and one was located in the second portion of the duodenum. Eighteen lesions (82%) had IIa morphology, and nine (41%) had central depression on the surface. On endoscopic ultrasonography, almost all lesions (20/22, 91%) were located in the second and/or third layers, and the median tumor size was 6 mm. During ME-NBI, the microsurface pattern was regular in 18 lesions (82%) and absent in 4 (18%). The microvascular pattern was regular in 17 lesions (77%), irregular in 4 (18%), and absent in 1 (5%). Thickened subepithelial vessels were observed in 15 (68%) lesions. There was no difference in tumor size according to the presence or absence of thickened subepithelial vessels (6.1 ± 1.8 mm vs. 5.9 ± 3.8 mm, p = 0.860). In conclusion, the characteristic ME-NBI findings of duodenal NETs were regular microsurface and microvascular patterns and the presence of thickened subepithelial vessels. These ME-NBI features may be useful for differentiating duodenal NETs from other duodenal subepithelial lesions.

Current status of the role of endoscopy in evaluation and management of gastrointestinal and pancreatic neuroendocrine tumors

The incidence of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) has increased over the last several decades. In general, NETs are slow-growing neoplasms and the data on the natural history is still evolving. The availability and improved utilization of advanced imaging modalities have allowed the selection of cases suitable for endotherapy. In this regard, endoscopic ultrasound (EUS) has emerged as a central imaging modality to assess the depth of infiltration in gastroduodenal as well as rectal NETs. Enhanced EUS modalities, including contrast-enhanced EUS and EUS elastography, reliably differentiate pancreatic neuroendocrine tumors (PNETs) from adenocarcinomas and may enable prediction of aggressive PNETs. With recent developments in therapeutic endoscopy, a large proportion of GEP-NETs can be safely managed endoscopically. Endoscopic resection techniques, including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), allow the safe removal of gastroduodenal and rectal NETs. Recent data indicate that modified EMR techniques may be superior to conventional EMR with regard to histologically complete resection. Device-assisted endoscopic full thickness resection is emerging as a safe and effective technique for upper gastrointestinal as well as rectal NETs. In selected cases with PNETs, who are otherwise unfit for surgery, EUS-guided ablation is increasingly being recognized as a safe treatment option. This review focusses on evidence-based approaches to endoscopic evaluation and the management of GEP-NETs with special emphasis on recent advancements.

Duodenal neuroendocrine tumors: analysis of 20 cases and endoscopic treatment

Analysis of 20 cases of duodenal neuroendocrine tumors (DNET). In 9 cases with 12 DNET, endoscopic treatment with hemorrhage or bleeding of 8,3.

Conventional endoscopic mucosal resection versus modified endoscopic mucosal resection for duodenal neuroendocrine tumor

BACKGROUND AND AIMS

As the incidence of duodenal neuroendocrine tumors (DNET) is steadily increasing, the role of endoscopic treatment for appropriate lesions is becoming more significant. We aimed to compare the outcomes according to lesion size and endoscopic mucosal resection (EMR) techniques for DNET treatment.

PATIENTS AND METHODS

Patients who underwent endoscopic treatment for DNET between June 2000 and December 2019 were included. The clinicopathologic features and treatment outcomes were investigated by reviewing medical records.

RESULTS

Overall, 104 cases underwent endoscopic resection for nonampullary DNET, including conventional EMR (n = 57), cap-assisted EMR (EMR-C, n = 19), and precut EMR (EMR-P, n = 28). The en bloc resection rates (100% vs. 94.7% vs. 96.4%) and histologic complete resection rates (45.6% vs. 52.6% vs. 57.1%) were not significantly different between the EMR, EMR-C, and EMR-P groups. The histologic complete resection rates were significantly higher in lesions < 10 mm than in lesions ≥ 10 mm (69.8% vs. 38.9%, P = 0.013). In lesions < 10 mm, perforation occurred more frequently in the modified EMR group than in the conventional EMR group (13.2% vs. 0.0%, P = 0.007). During the median follow-up period of 88.0 months, the recurrence-free survival (92.2% vs. 94.4% vs. 92.1%) and overall survival (98.0% vs. 88.1% vs. 100.0%) rates did not show significant differences between the EMR, EMR-C, and EMR-P groups.

CONCLUSION

Conventional EMR and modified EMR are feasible and effective for the treatment of nonampullary DNET sized < 10 mm and limited to mucosal and submucosal layer. Additionally, endoscopists should be aware of the high risk of perforation in modified EMR.

Development and Validation of Prognostic Nomograms for Periampullary Neuroendocrine Neoplasms: A SEER Database Analysis

(1) Background: Periampullary neuroendocrine neoplasms (NENs) are rare tumors that lack a prognostic prediction model. We aimed to design comprehensive and effective nomograms to predict prognosis; (2) Methods: Univariate and multivariate Cox analyses were used to screen out significant variables for the construction of the nomograms. The discrimination and calibration of the nomograms were carried out using calibration plots, concordance indices (C-indices), and area under time-dependent receiver operating characteristic curves (time-dependent AUCs). Decision curve analysis (DCA) was used to compare the clinical applicability of the nomograms, TNM (Tumor- Node-Metastasis) stage, and SEER stage; (3) Results: The independent risk factors for overall survival (OS) and cancer-specific survival (CSS) of patients with periampullary NENs included age, tumor size, histology, differentiation, N stage, M stage, and surgery, which were used to construct the nomograms. The calibration curves and C-indices showed a high degree of agreement between the predicted and actual observed survival rates. The AUCs displayed good calibration and acceptable discrimination of the nomograms. Additionally, the DCA curves indicated that the nomograms showed better clinical applicability; (4) Conclusions: We developed and validated nomogram prognostic models for patients with periampullary NENs. The nomograms provided insightful and applicable tools to evaluate prognosis.

Diagnostic features and management options for duodenal neuroendocrine neoplasms: a retrospective, multi-centre study

Duodenal neuroendocrine neoplasms (dNENs) are rare neoplasms but their incidence is on the rise. They are classified into 5 sub-types but there remains much heterogeneity in behaviour in particular of non-functioning dNENs. To retrospectively analyse outcomes for all types of dNENs, and highlight prognostic factors associated with worse outcome. 102 (57 m/45f.) patients were identified with mean age at diagnosis 62 (range 32–87) years. The majority were non-functioning tumours 87/102 and median size was 10 mm (range 0.9–130 mm). 83 patients had Stage I or II disease, of which 17 underwent endoscopic resection with R1 rate of 45% and complication rate 12%. 36 patients were kept under endoscopic surveillance. There were 11 deaths of which 4 were disease related. Age and Ki67 > 20% were associated with worse OS in all dNENs. In non-functioning dNENs Ki67 > 3% was a predictor of lymph nodes metastases with OR 18.2 (2.54–13) (p < 0.005) in univariate analyses and liver metastases with OR 6.79 (1.56–29.5) (p < 0.05) in the multivariate analysis. Lesions 11–20 mm in size had OR 11.1 (1.16–106) compared to lesions < 11 mm for the prediction of lymph node metastases in the multivariate analysis (p < 0.05). ROC analysis of size of non-functioning dNENs to predict LN metastases found < 15 mm had an AUROC of 0.9 (0.81–0.99) with a sensitivity of 85% and specificity of 88%. dNENs are increasing in incidence, however low grade and smaller lesions have an indolent course and the role of endoscopic resection and active surveillance needs to be reviewed.

Clinical outcomes of gastroduodenal neuroendocrine tumors according to their WHO grade: A single-institutional retrospective analysis

The management of gastroduodenal neuroendocrine tumor (NET) has been controversial between radical surgical resection and local excision including endoscopic resection. A gastroduodenal NET grade (G), measured by their mitotic rate and Ki67 proliferation index, is important to predict prognosis. In this study, we aimed to compare the clinical outcomes of gastroduodenal NET according to grades in order to identify poor prognostic factors of gastroduodenal NETs. Fifty-four gastroduodenal NETs diagnosed between December 2008 and December 2020 in a tertiary referral hospital were retrospectively reviewed. The clinical outcomes of gastroduodenal NETs, according to tumor grades and factors associated with NET G2-3, were analyzed. A total of 52 gastroduodenal NET patients was enrolled. The mean follow-up period was 56.2 ± 40.1 months. The mean size of gastric and duodenal NET was 7.9 ± 11.0 mm and 9.8 ± 7.6 mm, respectively. During the study period, 72.7% (16/22) of gastric NETs and 83.3% (25/30) of duodenal NETS were G1. All G1 gastroduodenal NETs showed no lymph node or distant metastasis during the study periods. All G3 gastroduodenal NETs showed metastasis (one lymph node metastasis and 3 hepatic metastases). Among metastatic NETs, the smallest tumor size was a 13 mm gastric G3 NET. Factors associated with G2-3 NETs were larger tumor size, mucosal ulceration, proper muscle or deeper invasion, and lymphovascular invasion. A small-sized gastroduodenal NET confined to submucosa without surface ulceration may be suitable for endoscopic resection. After local resection of a gastroduodenal NET (G1) without lymphovascular and muscle proper invasion, follow-up examination without radical surgical resection can be recommended. G3 NETs may be treated by radical surgical resection, regardless of tumor size.

Gastroenteropancreatic Neuroendocrine Tumors

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are the most common type of neuroendocrine tumors and are being increasingly identified in clinical practice. The diagnosis, staging, management, and surveillance of GEP-NETs rely heavily on endoscopy, and consequently, it is important for gastroenterologists to have a solid understanding of these tumors. This article reviews the presentation, diagnosis, and management of both localized and advanced GEP-NETs, with increased emphasis on the role of endoscopy, to enable gastroenterologists and other practitioners to have the necessary tools for the care of patients with these tumors.

Endoscopic techniques for diagnosis and treatment of gastro-entero-pancreatic neuroendocrine neoplasms: Where we are

BACKGROUND

The correct localization of the primary tumor site and a complete histological diagnosis represent the milestones for the proper management of gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs).

AIM

To analyze current evidence on the role of endoscopy in the diagnosis/treatment of GEP-NENs.

METHODS

An extensive bibliographical search was performed in PubMed to identify guidelines and primary literature (retrospective and prospective studies, systematic reviews, case series) published in the last 15 years, using both medical subject heading (MeSH) terms and free-language keywords: gastro-entero-pancreatic neuroendocrine neoplasms; endoscopy; ultrasound endoscopy; capsule endoscopy; double-balloon enteroscopy; diagnosis; therapy; staging.

RESULTS

In the diagnostic setting, endoscopic ultrasonography (EUS) represents the diagnostic gold standard for pancreatic NENs and the technique of choice for the locoregional staging of gastric, duodenal and rectal NENs. The diagnosis of small bowel NENs (sbNENs) has been improved with the advent of video capsule endoscopy and double-balloon enteroscopy, which allow for direct visualization of the entire small bowel; however, data regarding the efficacy/safety of these techniques in the detection of sbNENs are scanty and often inconclusive. From a therapeutic point of view, endoscopic removal is the treatment of choice for the majority of gastric NENs (type 1/2), for well-differentiated localized nonmetastatic duodenal NENs < 1 cm, confined to the submucosa layer and for < 10 mm, stage T1–T2, rectal NENs. EUS-guided pancreatic locoregional ablative treatments have been proposed in recent studies with promising results in order to control symptoms or reduce tumor burden in selected patients.

CONCLUSION

Standard axial endoscopy and EUS still play a pivotal role in several GEP-NENs. Advanced techniques for increasing the rate of R0 resection should be reserved for high-volume referral centers.

Endoscopic mucosal resection using a ligation device for duodenal neuroendocrine tumors: a simple method

Introduction:

Duodenal neuroendocrine tumors (DNETs) smaller than 1 cm in diameter, without invasion to the muscularis propria, have a low risk of metastasis. Therefore, DNETs are frequently resected endoscopically. However, among the various procedures, the best fit for DNET in terms of feasibility, effectiveness, and simplicity is unclear.

Methods:

Patients with DNET who underwent endoscopic submucosal resection using a ligation device (ESMR-L) at Kanagawa Cancer Center between May 2003 and December 2020 were studied retrospectively to evaluate clinical characteristics and short-term and long-term outcomes.

Results:

Eleven consecutive patients with 12 lesions were treated with 12 sessions of ESMR-L. Lesions were discovered in patients at a median age of 68 (range, 50–83) years. One patient had two lesions at the time of the initial ESMR-L session. Eleven of the 12 lesions (91.7%) existed in the duodenal bulb, of which 10 (83.3%) were in the anterior wall, and the remaining one (8.3%) existed in the descending part of the duodenum. The en bloc and R0 resection rates were 100% and 75%, respectively. The rates of bleeding and perforation were both 0%. Among the four patients who had non-curative resections, two patients underwent additional surgery after ESMR-L. One patient had a local remnant tumor, and the other had lymph node metastasis. In cases of local remnant tumors, the vertical margin was positive in the ESMR-L specimen. In that case, ligation by the O-ring was insufficient, retrospectively. All patients had no recurrence during the median follow-up period of 5.7 years.

Discussion:

ESMR-L was the best fit for DNET within the indications for endoscopic resection. It is a simple procedure that enables easy and complete resection of DNETs without complications.

State of the Art in Endoscopic Therapy for the Management of Gastroenteropancreatic Neuroendocrine Tumors

OPINION STATEMENT

Gastroenteropancreatic neuroendocrine neoplasms (GEP NENs) comprise a heterogeneous group of slow growing tumors arising from the neuroendocrine cells of the gastrointestinal (GI) tract. Although they are considered relatively rare, their incidence is rising and it is believed that the more frequent use of endoscopy and imaging studies have at least in part contributed to the increased diagnosis especially of localized neoplasms. The management of these neoplasms should be guided by a multidisciplinary NEN team following appropriate staging investigations. Localized neoplasms of the GI tract may be suitable for endoscopic therapy, while patients with pancreatic NENs, unsuitable for surgery, should be considered for endoscopic ultrasound (EUS)-guided ablation. In this review, we discuss the evidence regarding endoscopic resection of luminal NENs and EUS-guided therapy of pancreatic NENs. The efficacy, safety, and other longer-term outcomes of these techniques are summarized. In conclusion, this review of endoscopic therapies for localized NENs may be a useful guide for NEN clinicians and endoscopists who are considering these therapeutic options for the management of focal GEP NENs.

Endoscopic management of subepithelial lesions including neuroendocrine neoplasms: European Society of Gastrointestinal Endoscopy (ESGE) Guideline

1: ESGE recommends endoscopic ultrasonography (EUS) as the best tool to characterize subepithelial lesion (SEL) features (size, location, originating layer, echogenicity, shape), but EUS alone is not able to distinguish among all types of SEL.Strong recommendation, moderate quality evidence. 2: ESGE suggests providing tissue diagnosis for all SELs with features suggestive of gastrointestinal stromal tumor (GIST) if they are of size > 20 mm, or have high risk stigmata, or require surgical resection or oncological treatment.Weak recommendation, very low quality evidence. 3: ESGE recommends EUS-guided fine-needle biopsy (EUS-FNB) or mucosal incision-assisted biopsy (MIAB) equally for tissue diagnosis of SELs ≥ 20 mm in size.Strong recommendation, moderate quality evidence. 4: ESGE recommends against surveillance of asymptomatic gastrointestinal (GI) tract leiomyomas, lipomas, heterotopic pancreas, granular cell tumors, schwannomas, and glomus tumors, if the diagnosis is clear.Strong recommendation, moderate quality evidence. 5: ESGE suggests surveillance of asymptomatic esophageal and gastric SELs without definite diagnosis, with esophagogastroduodenoscopy (EGD) at 3-6 months, and then at 2-3-year intervals for lesions < 10 mm in size, and at 1-2-year intervals for lesions 10-20 mm in size. For asymptomatic SELs > 20 mm in size that are not resected, ESGE suggests surveillance with EGD plus EUS at 6 months and then at 6-12-month intervals.Weak recommendation, very low quality evidence. 6: ESGE recommends endoscopic resection for type 1 gastric neuroendocrine neoplasms (g-NENs) if they grow larger than 10 mm. The choice of resection technique should depend on size, depth of invasion, and location in the stomach.Strong recommendation, low quality evidence. 7: ESGE suggests considering removal of histologically proven gastric GISTs smaller than 20 mm as an alternative to surveillance. The decision to resect should be discussed in a multidisciplinary meeting. The choice of technique should depend on size, location, and local expertise.Weak recommendation, very low quality evidence. 8: ESGE suggests that, to avoid unnecessary follow-up, endoscopic resection is an option for gastric SELs smaller than 20 mm and of unknown histology after failure of attempts to obtain diagnosis.Weak recommendation, very low quality evidence. 9: ESGE recommends basing the surveillance strategy on the type and completeness of resection. After curative resection of benign SELs no follow-up is advised, except for type 1 gastric NEN for which surveillance at 1-2 years is advised.Strong recommendation, low quality evidence. 10: For lower or upper GI NEN with a positive or indeterminate margin at resection, ESGE recommends repeating endoscopy at 3-6 months and another attempt at endoscopic resection in the case of residual disease.Strong recommendation, low quality evidence.

Therapeutic strategies for gastroenteropancreatic neuroendocrine neoplasms: State-of-the-art and future perspectives

Although gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have always been considered rare tumors, their incidence has risen over the past few decades. They represent a highly heterogeneous group of neoplasms with several prognostic factors, including disease stage, proliferative index (Ki67), and tumor differentiation. Most of these neoplasms express somatostatin receptors on the cell surface, a feature that has important implications in terms of prognosis, diagnosis, and therapy. Although International Guidelines propose algorithms aimed at guiding therapeutic strategies, GEP-NEN patients are still very different from one another, and the need for personalized treatment continues to increase. Radical surgery is always the best option when feasible; however, up to 80% of cases are metastatic upon diagnosis. Regarding medical treatments, as GEP-NENs are characterized by relatively long overall survival, multiple therapy lines are adopted during the lifetime of these patients, but the optimum sequence to be followed has never been clearly defined. Furthermore, although new molecular markers aimed at predicting the response to therapy, as well as prognostic scores, are currently being studied, their application is still far from being part of daily clinical practice. As they represent a complex disease, with therapeutic protocols that are not completely standardized, GEP-NENs require a multidisciplinary approach. This review will provide an overview of the available therapeutic options for GEP-NENs and attempts to clarify the possible approaches for the management of these patients and to discuss future perspectives in this field.

Histopathologic discrepancies between endoscopic forceps biopsy and endoscopic resection specimens in nonampullary duodenal epithelial tumors

For patients with nonampullary duodenal epithelial tumors (NADETs), endoscopic forceps biopsy results that reflect the final histopathologic results of the entire lesion are indispensable for accurate diagnosis and appropriate treatment modality selection. This study aimed to investigate the histopathologic discrepancies between endoscopic forceps biopsy and endoscopic resection specimens in NADETs and to elucidate the factors contributing to such discrepancies.This retrospective observational study included 105 patients (105 lesions) who underwent endoscopic resection for NADETs at the Pusan National University Hospital between May 2006 and October 2019. NADETs were classified as low-grade intraepithelial neoplasms (LGINs), high-grade intraepithelial neoplasms (HGINs), or adenocarcinomas. Following slide reviews, the histopathologic concordance between endoscopic forceps biopsy and endoscopic resection specimens was assessed for each case.The histopathologic discrepancy rate between endoscopic forceps biopsy and endoscopic resection specimens was 19.0% (20/105 lesions). Among the 20 diagnostically discordant lesions, up- and downgrade of the histopathologic diagnosis occurred in 17 and 3 lesions, respectively. The predominant discrepancies involved upgrades from LGIN to HGIN (n = 14) and upgrades from LGIN to adenocarcinomas (n = 2). The 3 downgraded cases included 2 from LGIN to inflammation and 1 from HGIN to LGIN. In the multivariate analyses, the old age (>67 years) was the only factor significantly associated with histopathologic upgrade (odds ratio 4.553, 95% confidence interval 1.291-15.939; P = .018).Considerable histopathologic discrepancies were observed between endoscopic forceps biopsy and endoscopic resection specimens in NADETs. Older age was significantly associated with these discrepancies.

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.

Risk of preoperative understaging of duodenal neuroendocrine neoplasms: a plea for caution in the treatment strategy

PURPOSE

Pretreatment staging is the milestone for planning either surgical or endoscopic treatment in duodenal neuroendocrine neoplasms (dNENs). Herein, a series of surgically treated dNEN patients was evaluated to assess the concordance between the pre- and postsurgical staging.

METHODS

Retrospective analysis of patients with a histologically confirmed diagnosis of dNENs, who underwent surgical resection observed at eight Italian tertiary referral centers. The presurgical TNM stage, based on the radiological and functional imaging, was compared with the pathological TNM stage, after surgery.

RESULTS

From 2000 to 2019, 109 patients were included. Sixty-six patients had G1, 26 a G2, 7 a G3 dNEN (Ki-67 not available in 10 patients). In 46/109 patients (42%) there was disagreement between the pre- and postsurgical staging, being it understaged in 42 patients (38%), overstaged in 4 (3%). As regards understaging, in 25 patients (22.9%), metastatic loco-regional nodes (N) resulted undetected at both radiological and functional imaging. Understaging due to the presence of distal micrometastases (M) was observed in 2 cases (1.8%). Underestimation of tumor extent (T) was observed in 12 patients (11%); in three cases the tumor was understaged both in T and N extent.

CONCLUSIONS

Conventional imaging has a poor detection rate for loco-regional nodes and micrometastases in the presurgical setting of the dNENs. These results represent important advice when local conservative approaches, such as endoscopy or local surgical excision are considered and it represents a strong recommendation to include endoscopic ultrasound in the preoperative tools for a more accurate local staging.

Neuroendocrine Tumors of the Gastrointestinal Tract: A Focused Review and Practical Approach for Gastroenterologists

Neuroendocrine tumors (NETs) are rare tumors derived from the neuroendocrine cell system, and more commonly found in the gastrointestinal (GI) tract. Over the last decades, the incidence of GI-NETs has been steadily increasing, partly due to the expanding indications for endoscopy. Most patients with NETs are asymptomatic, and their NETs are noticed during screening examinations; thus, endoscopists are on the frontline of the diagnosis of GI-NETs. Since GI-NETs are less frequent than other malignancies, the natural history, diagnosis, and management of these tumors may not be fully understood. In this review, we aim to update the endoscopist on key clinical features and management of patients with gastric, duodenal, and rectal NETs.

Impact of margin status on outcomes after endoscopic resection of well-differentiated duodenal neuroendocrine tumors

BACKGROUND AND AIMS

Duodenal neuroendocrine tumors (DNETs) are known to have low metastatic potential and follow an indolent course. Although DNETs <1 cm in size are amenable to endoscopic resection, little is known about the long-term outcomes and recurrence rates of this approach.

METHODS

Sixty-three patients with DNETs from 3 centers were retrospectively studied from 2003 to 2018. We analyzed their resection modality (EMR, snare polypectomy, or forceps polypectomy), margin status, risk factors for recurrence, recurrence rate, and endoscopic surveillance patterns.

RESULTS

Of the 63 patients who underwent endoscopic resection, 13 (20.6%) had recurrence. The presence of R1 margins was found to be a statistically significant risk factor for recurrence (P = .048). Mean surveillance time for all DNETs was 2.8 ± 2.6 years. Ninety-two percent of recurrences were detected within 3 years of resection.

CONCLUSIONS

Our data suggest that the main predictor of recurrence in low-grade DNETs <1.0 cm is the presence of positive tumor margins at the initial endoscopic resection. More frequent, earlier surveillance after resection than that currently recommended by European Neuroendocrine Tumor Society guidelines may be warranted to promptly capture DNET recurrences. Additionally, no recurrences occurred in our cohort after 4 years of surveillance.

Survival and Disease Recurrence in Patients with Duodenal Neuroendocrine Tumours-A Single Centre Cohort

Simple Summary

Neuroendocrine tumours of the upper part of the small intestine are rare. They are slow growing but may spread to lymph nodes or other organs already when the tumours are small. Such tumours may be treated by endoscopic removal or by an operation. In the current study we present the treatment results of 32 patients with this rare tumour. We found that the long-term survival was long, and patients more often died from other diseases. The survival was associated with the growth rate of the tumours and whether all the tumour tissue could be removed. Endoscopic removal was sufficient for smaller tumours <10 mm, whereas a high proportion of tumours 10–20 mm have lymph node metastases that must be removed by an operation to make patients tumour free. None of the tumours that were perceived as cured after removal recurred after an average follow-up time of 4.8 years.

Abstract

Background: Duodenal neuroendocrine tumours (D-NETs) are rare but increasingly diagnosed. This study aimed to assess the overall survival and recurrence rate among patients treated for D-NETs. Methods: Patients with D-NETs were retrospectively reviewed with a median follow-up time of 4.8 years (range 0.0–17.2 years). Results: A total of 32 patients with median age 68.0 years were identified. Fifteen patients underwent surgery while ten patients underwent endoscopic treatment. Mean estimated overall survival for the entire population was 12.1 years (95% CI 9.5–14.7 years), while 5-year overall survival was 81.3%. Tumour grade G1 was associated with longer mean estimated survival compared to G2 tumours (13.2 years versus 4.4 years, p = 0.010). None of the 23 patients who underwent presumed radical endoscopic or surgical resection had disease recurrence during follow-up. Tumours <10 mm could be treated endoscopically whereas a high proportion of patients with tumours 10–20 mm should be considered for surgery. Conclusion: Patients with D-NETs had long overall survival, and mortality was more influenced by other diseases. Both endoscopic and surgical resections were effective as no recurrences were diagnosed during follow-up.

Comparison of endoscopic resection techniques for duodenal neuroendocrine tumors: systematic review

Background and study aims  Regardless of size, duodenal neuroendocrine tumors (dNETs) should be considered potentially malignant. A complete resection without complications is essential to increase safety procedures. The aim of this review was to describe effectiveness and possible complications of endoscopic techniques resection for resectioning dNETs in patients with tumors ≤ 20 mm in diameter. Methods  An electronic bibliographic search was conducted using MEDLINE (via PubMed), Embase, Cochrane Central, and Google Scholar virtual databases. The types of intervention were endoscopic mucosal resection alone (EMR) or with cap (EMR-C), with a ligation device (EMR-L), with previous elevation of the tumor (EMR-I) or with endoscopic submucosal dissection (ESD); argon plasm coagulation (APC), and polypectomy. The outcome measures adopted were presence of free margin associated with tumor resection, tumor recurrence, complications (bleeding and perforation), and length of the procedure. Results  Ten publications were included with the result of 224 dNET resections. EMR alone and polypectomy resulted in the most significantly compromised margin. The most frequent complication was bleeding (n = 21), followed by perforation (n = 8). Recurrence occurred in 13 cases, the majority of those under EMR or EMR-I. Conclusions  EMR-C or EMR-I should be preferred for resectioning of dNETs. Polypectomy should not be indicated for resection of dNETs due to the high occurrence of incomplete resections. EMR alone must be avoided due a higher frequency of compromised margin and recurrent surgery. ESD was associated with no recurrence, however, but an increased occurrence of bleeding and perforation.

Risk factors for lymph node metastasis and survival of patients with nonampullary duodenal carcinoid tumors treated with endoscopic therapy versus surgical resection: analysis of the Surveillance, Epidemiology, and End Results program

BACKGROUND AND AIMS

Endoscopic therapy (ET) has been used to treat nonampullary duodenal neuroendocrine tumors (NAD-NETs) ≤10 mm in size, but data on long-term outcomes are limited. In addition, management of 11- to 19-mm NAD-NETs is not well defined because of variable estimates of risk of metastasis. We aimed to determine the prevalence and risk factors of metastasis of NAD-NETs ≤19 mm and evaluate the long-term survival of patients after ET as compared with radical surgery.

METHODS

The Surveillance Epidemiology and End Result database was used to identify 1243 patients with T1-2 histologically confirmed NAD-NETs ≤19 mm in size. Cancer-specific survival (CSS) and overall survival (OS) were calculated.

RESULTS

Overall, 4.8% of cases had metastasis at the time of diagnosis, with lower prevalence in ≤10-mm lesions (3.1%) versus 11- to 19-mm lesions (11.7%, P < .001). The risk factors for metastases included invasion to the muscularis propria (odds ratio, 25.95; 95% confidence interval, 9.01-76.70), age <65 years (odds ratio, 1.93), submucosal involvement (odds ratio, 3.1), and 11 to 19 mm in size (vs ≤10 mm). In patients with well- to moderately differentiated T1-2N0M0 NAD-NETs ≤19 mm confined to the mucosa/submucosa who underwent ET or surgery, the 5-year CSS was 100%. The 5-year OS was similar between the ≤10-mm and 11- to 19-mm groups (86.6% vs 91.0%, P = .31) and the ET and surgery groups (87.4% vs 87.5%, P = .823).

CONCLUSIONS

In NAD-NETs, invasion to the muscularis propria is the strongest risk factor for metastasis. In the absence of metastasis, in lesions with well/moderate differentiation and without muscle invasion, ET is adequate for NAD-NETs ≤10 mm and is a viable option for 11- to 19-mm lesions.

Endoscopic resection using an over-the-scope clip for duodenal neuroendocrine tumors

Background and study aims  Endoscopic resection of duodenal neuroendocrine tumors (DNETs) remains controversial, and its indications are still unclear. This study aimed to evaluate short-term outcomes of a newly developed endoscopic muscularis resection (EMR) method that utilizes an over-the-scope clip (OTSC), termed EMRO, for treating DNETs. Patients and methods  In total, 13 consecutive patients with 14 small (≤ 10 mm) DNETs who underwent EMRO from September 2017 to March 2020 were retrospectively enrolled. EMRO was performed by a single experienced endoscopist. Patients' characteristics and treatment outcomes were assessed. Results  The En bloc and R0 resection rates were 100 % (14/14) and 92.9 % (13/14), respectively. The median pathological resected specimen size was 10 mm, with a median pathological resected tumor size of 6 mm. During the EMRO procedure, there was no occurrence of misplacement of the OTSC to the target lesion. With respect to the pathological resection depth, nine cases (64.3 %) and five cases (35.7 %) were categorized as deep submucosal resection and muscularis resection, respectively, whereas no case was categorized as full-thickness resection. There were no intraoperative or delayed perforations. However, delayed bleeding occurred in two cases. At a median follow-up of 12 months (range 7-36) after EMRO, there was no incidence of local recurrence. At the first follow-up endoscopy performed at 6 months after EMRO, the OTSC was retained in place in two of 14 DNETs (14.3 %). Conclusions  EMRO can be performed safely, by an experienced endoscopist, for small (≤ 10 mm) DNETs.

Endoscopic Treatment for Superficial Nonampullary Duodenal Tumors

Superficial nonampullary duodenal epithelial tumors are considered rare but have been increasingly recognized in recent years. Accordingly, the importance of endoscopic treatment for the lesions are also increasing. An endoscopic resection can be considered for duodenal adenoma and mucosal cancer. The choice of resection method should be made based on the size of the lesion, endoscopic findings, pathologic diagnosis, and risk of procedure-related complication. For small adenomas <10 mm in size, endoscopic mucosal resection (EMR), cold snare polypectomy, and underwater EMR can be considered. An en bloc or piecemeal resection using EMR or underwater EMR can be selected for 10-20 mm sized adenomas. For lesions ≥20 mm in size or suspicious for mucosal cancer, an endoscopic submucosal dissection followed by closure of the mucosal defect conducted by an experienced endoscopist is appropriate.

The Role of Endoscopy in Small Bowel Neuroendocrine Tumors

Small bowel neuroendocrine tumors (NETs) represent approximately one-third of NETs of the gastrointestinal tract, and their incidence is increasing. When determining if endoscopic resection is appropriate, endoscopic ultrasound is used to assess the lesion size and depth of invasion for duodenal NETs. A number of techniques, including endoscopic mucosal resection (EMR), band-assisted EMR (band-EMR), endoscopic submucosal dissection (ESD), and over-the-scope clip-assisted endoscopic full-thickness resection (EFTR), have been studied; however, the best technique for endoscopic resection remains unclear. The vast majority of currently available data are retrospective, and prospective studies with longer follow-up times are required. For jejunal and ileal NETs, endoscopic techniques such as video capsule endoscopy (VCE) and balloon enteroscopy (BE) assist in diagnosis. This includes localization of the primary NET in metastatic disease where initial workup has been negative, and the identification of multifocal disease, which may change management and prognostication.

Safety and efficacy of endoscopic resection for the treatment of duodenal subepithelial lesions

Background

Endoscopic management of duodenal subepithelial lesions is challenging, and there are only a few studies on this topic. This study aimed to evaluate the safety and efficacy of endoscopic resection for the treatment of duodenal subepithelial lesions.

Methods

We retrospectively analyzed the clinical data, including epidemiologic characteristics, therapeutic outcomes, complications, and follow-up results, of 49 patients with duodenal subepithelial lesions who underwent endoscopic resection at our hospital between August 2010 and September 2019.

Results

We performed 35 endoscopic submucosal dissection, 9 endoscopic mucosal resection, 3 endoscopic submucosal excavation, and 2 endoscopic full-thickness resection. The en bloc resection rate and R0 resection rate were 95.9% and 89.8%, respectively. Delayed perforations developed in 2 (4.1%) patients; surgical intervention was required for both. Coagulation syndrome developed in 1 (2.0%) patient; however, it was treated conservatively. Delayed bleeding or other serious complications did not occur. One patient underwent complementary surgery after endoscopic resection. One (2.3%) recurrence occurred in patients who underwent endoscopic resection at a median follow-up duration of 24 months (range, 1-88 months).

Conclusions

Endoscopic resection is an effective, safe, and minimally invasive method for the histopathologic assessment and curative treatment of duodenal subepithelial lesions originating from the submucosal or muscularis propria.

Endoscopic Treatment of Gastric and Duodenal Neuroendocrine Tumors: Present and Future

Gastric and duodenal neuroendocrine tumors (NETs) are not common; however, there is an increase in the incidence due to increased use of endoscopy. Endoscopic treatment has been applied to treat small NET G1 in the stomach and duodenum. For the endoscopic treatment of NETs, it is necessary to evaluate tumor size, depth of invasion, and lymphatic and distant metastasis. This article will review the current knowledge concerning the endoscopic treatment of gastric and duodenal neuroendocrine tumors.

The value of endoscopic resection for non-ampullary duodenal lesions: A single-center experience

BACKGROUND

To observe and preliminarily evaluate the efficacy and safety of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) in the treatment of non-ampullary duodenal lesions (NADLs).

METHODS

This retrospective observational study included 84 patients who underwent endoscopic resection (ER) with non-ampullary duodenal lesions, between March 2010 and November 2020, at the Cancer Hospital of the Chinese Academy of Medical Sciences (Beijing, China). Data on patient demographics, therapeutic outcomes, and follow-up results were analyzed.

RESULTS

There were 44 patients undergoing EMR, and 40 patients accepting ESD. The overall en bloc resection rate was 98.8% (83/84). For the neoplastic lesions, the overall en bloc resection rate and curative rate were 98.5% (67/68) and 89.7% (61/68), respectively. The procedure-related bleeding and perforation rates were 2.4% and 10.7%, respectively. Univariate analysis results indicated that the main correlation factor of non-curative pathologic resection was tumor size (p = 0.004) and resection size (P < 0.01). There showed a higher curative rate in patients with tumors less than 25 mm in diameter. Multivariate logistic regression analyses determined that the tumor size (OR 0.935; 95% CI 0.878-0.995; P = 0.035) was associated with non-curative resection. No recurrences were observed in patients who had undergone a complete ER during a follow-up period of 42.8 months (range, 3-127 months).

CONCLUSION

Endoscopic resection is an effective, safe, and feasible treatment for non-ampullary duodenal lesions.

Management and Prognosis of Localized Duodenal Neuroendocrine Neoplasms

INTRODUCTION

The characteristics, prognostic factors, and management of duodenal neuroendocrine neoplasms (dNEN) are ill-defined, given their rarity. Whether nonsurgical management might be appropriate for patients with nonmetastatic dNEN and a good prognosis, as is the case for pancreatic NEN (pNEN), is unknown. We aimed to describe the management and prognosis of nonmetastatic dNEN patients.

METHODS

All consecutive patients with nonmetastatic dNEN managed between 1981 and 2018 in 2 expert centers were included. Recurrence-free survival (RFS) and factors associated with recurrence were estimated.

RESULTS

A total of 145 patients with dNEN were included. Twenty-eight patients with sporadic, nonfunctioning, small (median 7 mm) dNEN underwent endoscopic resection, with a 5-year RFS rate of 89.4%. Local recurrence occurred in 2 patients, who underwent surgery with no new events. The 5-year RFS rate was 87.9% in patients who underwent surgery. Upon univariate analysis, age, size, Ki67 index, and lymph node involvement (LN+) were significantly associated with worse RFS for all dNEN treated (endoscopy/surgery); multivariate analysis found that age, size, and LN+ were associated with worse RFS.

CONCLUSION

Selected nonmetastatic dNEN had a favorable outcome, and a less invasive therapeutic strategy appeared more suitable than oncological surgery.

Application of endoscopic submucosal dissection in duodenal space-occupying lesions

BACKGROUND

Endoscopic submucosal dissection (ESD) has been advocated by digestive endoscopists because of its comparable therapeutic effect to surgery, reduced trauma, faster recovery, and fewer complications. However, ESD for lesions of the duodenum is more challenging than those occurring at other levels of the gastrointestinal tract due to the thin intestinal wall of the duodenum, narrow intestinal space, rich peripheral blood flow, proximity to vital organs, and high risks of critical adverse events including intraoperative and delayed bleeding and perforation. Because of the low prevalence of the disease and the high risks of severe adverse events, successful ESD for lesions of the duodenum has rarely been reported in recent years.

AIM

To investigate the efficacy and safety of ESD in the treatment of duodenal space-occupying lesions.

METHODS

Clinical data of 24 cases of duodenal lesions treated by ESD at the Digestive Endoscopy Center of the Affiliated Hospital of Qingdao University from January 2016 to December 2019 were retrospectively analyzed.

RESULTS

All of the 24 cases from 23 patients underwent ESD treatment for duodenal space-occupying lesions under general anesthesia, including 15 male and 8 female patients, with a mean age of 58.5 (32.0-74.0) years. There were 12 lesions (50%) in the duodenal bulb, 9 (37.5%) in the descending part, and 3 (12.5%) in the ball-descending junction. The mean diameter of the lesion was 12.75 (range, 11-22) mm. Thirteen lesions originated from the mucosa, of which 4 were low-grade intraepithelial neoplasia, 3 were hyperplastic polyps, 2 were chronic mucositis, 2 were adenomatous hyperplasia, 1 was high-grade intraepithelial neoplasia, and 1 was tubular adenoma. Eleven lesions were in the submucosa, including 5 neuroendocrine neoplasms, 2 cases of ectopic pancreas, 1 stromal tumor, 1 leiomyoma, 1 submucosal duodenal adenoma, and 1 case of submucosal lymph follicular hyperplasia. The intraoperative perforation rate was 20.8% (5/24), including 4 submucosal protuberant lesions and 1 depressed lesion. The mean length of hospital stay was 5.7 (range, 3-10) d, and the average follow-up time was 25.8 (range, 3.0–50.0) mo. No residual disease or recurrence was found in all patients, and no complications, such as infection and stenosis, were found during the follow-up period.

CONCLUSION

ESD is safe and effective in the treatment of duodenal lesions; however, the endoscopists should pay more attention to the preoperative preparation, intraoperative skills, and postoperative treatment.

Systematic review: management of localised low-grade upper gastrointestinal neuroendocrine tumours

BACKGROUND

Neuroendocrine tumours (NETs) of the stomach and duodenum are rare, but are increasing in incidence. Optimal management of localised, low-grade gastric and duodenal NETs remains controversial.

AIMS

To systematically review recent literature that has evaluated the management of localised low-grade gastric and duodenal NETs.

METHODS

A systematic literature search was conducted. Articles were screened and eligible articles fully assessed. Additional articles were identified through the included articles' reference lists.

RESULTS

Several relevant retrospective case series were identified, but there was considerable heterogeneity between studies and they reported a variety of parameters. Type I gastric NETs had an excellent prognosis and conservative management approaches such as endoscopic surveillance/resection were appropriate in most cases. Many type III gastric NETs were low grade and appeared to have a better prognosis than has previously been appreciated. Endoscopic rather than surgical resection was therefore effective in some patients who had small, low-grade tumours. Duodenal NETs were more heterogenous. Endoscopic resection was generally safe and effective in patients who had small, low-grade, nonfunctional, non-ampullary tumours. However, some patients, especially those with larger or ampullary duodenal NETs, required surgical resection.

CONCLUSIONS

Most type I gastric NETs behave indolently and surgical resection is only rarely indicated. Some type III gastric and duodenal NETs have a worse prognosis, but selected patients who have small, localised, nonfunctional, low-grade tumours are adequately and safely treated by endoscopic resection. Due to the complexity of this area, a multidisciplinary approach to management is strongly recommended.

Digestive Neuroendocrine Neoplasms (NEN): French Intergroup clinical practice guidelines for diagnosis, treatment and follow-up (SNFGE, GTE, RENATEN, TENPATH, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, SFR)

INTRODUCTION

This document is a summary of the French Intergroup guidelines regarding the management of digestive neuroendocrine neoplasms (NEN) published in February 2020 (www.tncd.org).

METHODS

All French medical societies involved in the management of NEN took part in this work. Recommendations were graded into four categories (A, B, C or D), according to the level of evidence found in the literature until May 2019.

RESULTS

The management of NEN is challenging because of their heterogeneity and the increasing complexity of diagnostic and therapeutic procedures. Pathological analysis is required for their diagnostic and prognostic characterization, which mainly relies on differentiation, grade and stage. The two main emergency situations are functioning syndromes and poorly-differentiated carcinoma. Chromogranin A is the main biochemical marker of NET, although of limited clinical interest. Initial characterization relies on morphological and isotopic imaging. The treatment of localized NET relies on watchful follow-up and local or surgical resection depending on its supposed aggressiveness. Treatment options for metastatic disease include surgery, somatostatin analogues, chemotherapy, targeted therapies, organ-driven locoregional therapies and peptide-receptor radionuclide therapy. As specific predictive factors of treatment efficacy are yet to be identified and head-to-head comparisons have not or only rarely been performed, the therapeutic strategy currently depends on prognostic factors. Cumulative toxicity and the impact of treatment on quality of life must be considered since survival is relatively long in most patients with NET.

CONCLUSION

These guidelines are proposed to achieve the most beneficial therapeutic strategy in clinical practice as the therapeutic landscape of NEN is becoming ever more complex. These recommendations are permanently being reviewed.

Short- and long-term outcomes of endoscopic submucosal dissection for non-ampullary duodenal neuroendocrine tumors

Background

Endoscopic resection is recommended for non-ampullary duodenal neuroendocrine tumors (NAD-NETs) ≤10 mm in diameter and confined to the submucosal layer, without lymph node or distant metastasis. However, the efficacy and safety of endoscopic submucosal dissection (ESD) for NAD-NET remains unclear. The aim of this study was to assess the short-term efficacy and safety and the long-term outcomes of ESD for NAD-NET.

Methods

Eight patients with 8 NAD-NETs who underwent ESD between 2015 and 2018 were included. The indications for ESD were: i) tumor ≤10 mm in diameter; ii) NET G1; iii) confined to the submucosal layer; and iv) without lymph node or distant metastasis. We retrospectively assessed the short- and long-term outcomes and safety.

Results

The median patient age was 69 (48-76) years. All tumors were located in the duodenal bulb and showed 0-Is morphology. The median size was 6.4 (3-9.3) mm. The rates of en bloc resection, histologically free horizontal and vertical margins, and curative resection were 100%, 88%, and 88%, respectively. Intraoperative and postoperative perforation each occurred in 13% of patients, all of whom were treated conservatively and avoided emergent surgery. Delayed bleeding was not observed. No local, lymph node or distant recurrence was observed during a median follow-up period of 34 (18.5-62.5) months.

Conclusions

The rates of en bloc and curative resection, and histologically free margins were sufficiently high. Although intraoperative and postoperative perforations occurred, emergency surgery was not needed. The results show that ESD is an efficacious and safe treatment for NAD-NET.

Advances in the Diagnosis and Management of Well-Differentiated Neuroendocrine Neoplasms

Neuroendocrine neoplasms constitute a diverse group of tumors that derive from the sensory and secretory neuroendocrine cells and predominantly arise within the pulmonary and gastrointestinal tracts. The majority of these neoplasms have a well-differentiated grade and are termed neuroendocrine tumors (NETs). This subgroup is characterized by limited proliferation and patients affected by these tumors carry a good to moderate prognosis. A substantial subset of patients presenting with a NET suffer from the consequences of endocrine syndromes as a result of the excessive secretion of amines or peptide hormones, which can impair their quality of life and prognosis. Over the past 15 years, critical developments in tumor grading, diagnostic biomarkers, radionuclide imaging, randomized controlled drug trials, evidence-based guidelines, and superior prognostic outcomes have substantially altered the field of NET care. Here, we review the relevant advances to clinical practice that have significantly upgraded our approach to NET patients, both in diagnostic and in therapeutic options.

Contemporary surgical management of the Zollinger-Ellison syndrome in multiple endocrine neoplasia type 1

About 30% of patients with MEN1 develop a Zollinger-Ellison syndrome. Meanwhile it is well established that the causative gastrinomas are almost exclusively localized in the duodenum and not in the pancreas, MEN1 gastrinomas occur multicentric and are associated with hyperplastic gastrin cell lesions and tiny gastrin-producing micro tumors in contrast to sporadic duodenal gastrinomas. Regardless of the high prevalence of early lymphatic metastases, the survival is generally good with an aggressive course of disease in only about 20% of patients. Symptoms can be controlled medically. The indication, timing, type, and extent of surgery are highly controversial and are discussed in detail in this article by a thorough and critical review of literature. More radical procedures, like partial pancreaticoduodenectomy, are weighed against less aggressive local excision of gastrinomas and the pros and cons of both approaches are discussed in terms of long-term morbidity, biochemical cure, and survival.