Endoscopic treatment of duodenal neuroendocrine tumors

Prevalence and risk factors for lymph node metastasis in duodenal neuroendocrine tumors: a systematic review and meta-analysis

BACKGROUND

Although the status of lymph node metastasis (LNM) is crucial in determining treatment strategy for duodenal neuroendocrine tumors (D-NETs), robust evidence for their potential LNM risk remains lacking. This systematic review aimed to summarize the prevalence and risk factors of LNM in D-NETs.

METHODS

This systematic review of electronic databases identified eligible case-control and cohort studies for D-NET resected either endoscopically or surgically, published from 1990 to 2023. The primary outcome was the pooled prevalence of LNM in D-NETs. Secondary outcomes included the pooled prevalence of LNM according to tumor location and functionality, as well as identifying pathological risk factors for LNM. Meta-analysis was performed.

RESULTS

We identified 36 studies that involved 1,396 patients with D-NETs, including 326 with LNM. The pooled prevalence of LNM in D-NETs was 22.7% (95% confidence interval [CI] 17.3-29.2%). The prevalence was high in ampullary/peri-ampullary D-NETs and functional D-NETs (46.8 and 53.3%, respectively), whereas it was low in non-functional, non-ampullary D-NETs (NAD-NETs) (9.5%). Pathological risk factors for LNM in NAD-NETs included tumor size > 10 mm (odds ratio [OR] 7.31 [95% CI 3.28-16.31]), tumor invasion into the muscularis propria or deeper (OR 7.79 [3.65-16.61]), lymphovascular invasion (OR 5.67 [2.29-14.06]), and World Health Organization grading of G2 (OR 2.47 [1.03-5.92]).

CONCLUSION

Approximately one-fourth of the patients with D-NETs had LNM. Endoscopic resection might be acceptable for non-functional NAD-NETs with diameters of 10 mm or less, but additional surgical resection with lymphadenectomy may be recommended for cases exhibiting pathological risk factors.

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.

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.

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.

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.

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.

Comparison of characteristics between true rectal neuroendocrine tumors and rectal hyperplastic polyps among patients with endoscope-diagnosed rectal neuroendocrine tumors

Background

To explore the white light endoscopy and endoscopic ultrasonography (EUS) features of rectal hyperplastic polyps (rHP) misdiagnosed as rectal neuroendocrine neoplasms (rNENs). In rNENs with a diameter of 5-10 mm, the endoscopic findings are not typical and some of them are similar to rHP, so it is not uncommon to misdiagnose rNENs as rHP. However, misdiagnosis of rHP as rNENs has not been reported in the literature, which can alert clinicians to the existence of this possibility and avoid over-treatment.

Methods

We collected 245 cases of rectal submucosal tumor (SMT) diagnosed by endoscopy in our hospital from January 2015 to December 2020 and 103 patients with suspected rNENs identified through endoscopy. A retrospective analysis was conducted of the shape, color, vascular dilatation, and boundary on the surface of the lesion under white light endoscope, and the source, boundary, and echo characteristics of EUS. We also analyzed the endoscopic features of rHP misdiagnosed as rNENs. Endoscopic diagnosis and pathological diagnosis were reviewed by a senior endoscopic expert and pathologist respectively. The counting data were tested and analyzed by χ2 test and Fisher exact probability method.

Results

A total of 103 cases of rNENs were diagnosed by endoscope, among whom 75 cases were confirmed as rNENs (72.8%) and 8 cases as rHP (7.8%) by histopathology. There was no significant difference between rNENs and rHP in terms of gender, age, clinical manifestation, shape and color of lesions, dilatation of blood vessels on the surface, and location of lesions. Meanwhile, there were significant differences in whether the boundary of the lesion was clear under white light endoscopy, and the source, echo, and boundary of the lesion under EUS.

Conclusions

The morphology of some rHP is similar to rNENs under endoscopy. The boundary is clear under white light endoscopy and the source, echo, and boundary under EUS are helpful for the diagnosis of rNENs and rHP.

Management of Duodenal Neuroendocrine Tumors: Surgical versus Endoscopic Mucosal Resection

BACKGROUND

Management of duodenal neuroendocrine tumors (DNETs) is not standardized, with smaller lesions (< 1-2 cm) generally treated by endoscopic mucosal resection (EMR) and larger DNETs by surgical resection (SR). This study reviewed how patients were selected for treatment and compared outcomes.

PATIENTS AND METHODS

Patients with DNETs undergoing resection were identified through institutional databases, and clinicopathologic data recorded. χ² and Wilcoxon tests compared variables. Survival was determined by Kaplan-Meier, and Cox regression tested association with survival.

RESULTS

Among 104 patients, 64 underwent EMR and 40 had SR. Patients selected for SR had larger tumor size, younger age, and higher T, N, and M stage. There was no difference in progression-free (PFS) or overall survival (OS) between SR and EMR. In 1-2 cm DNETs, there was no difference in PFS between SR and EMR [median not reached (NR), P = 0.1]; however, longer OS was seen in SR (median NR versus 112 months, P = 0.03). In 1-2 cm DNETs, SR patients were more likely to be node-positive and younger. After adjustment for age, resection method did not correlate with survival. Comparison of surgically resected DNETs versus jejunoileal NETs revealed longer PFS (median NR versus 73 months, P < 0.001) and OS (median NR versus 119 months, P = 0.004) DISCUSSION: In 1-2 cm DNETs, there was no difference in survival between EMR and SR after adjustment for age. Recurrences could be salvaged, suggesting that EMR is a reasonable strategy. Compared with jejunoileal NETs, DNETs treated by SR had improved PFS and OS.

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.

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.

Development and Validation of Prognostic Nomograms for Patients with Duodenal Neuroendocrine Neoplasms

Background

This study was designed to predict prognosis of patients with primary duodenal neuroendocrine neoplasms (D-NENs) by developing nomograms.

Material/Methods

Patients diagnosed with D-NENs between 1988 and 2015 were queried from the SEER database and a total of 965 appropriate cases were randomly separated into the training and validation sets. Kaplan-Meier analysis was used to generated survival curves, and the difference among the groups was assessed by the log-rank test. Independent prognostic indicators were acquired by Cox regression analysis, and were used to develop predictive overall survival (OS) and cancer-specific survival (CSS) nomograms. Harrell’s concordance index (C-index), area under the curve (AUC), calibration curves, and decision curve analysis (DCA) were used to assess the efficacy of nomograms. Tumor stage was regarded as a benchmark in predicting prognostic compared with the nomograms built in this study.

Results

The C-index was 0.739 (0.690–0.788) and 0.859 (0.802–0.916) for OS and CSS nomograms, respectively. Calibration curves exhibited obvious consistency between the nomograms and the actual observations. In addition, C-index, AUC, and DCA were better than tumor stage in the evaluative performance of nomograms.

Conclusions

The nomograms were able to predict the 1-, 5-, and 10-year OS and CSS for D-NENs patients. The good performance of these nomograms suggest that they can be used for evaluating the prognosis of patients with D-NENs and can facilitate individualized treatment in clinical practice.

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.

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.

Endoscopic Resection of Duodenal Carcinoid Tumors: A Single-Center Comparison Between Simple Polypectomy and Endoscopic Mucosal Resection

OBJECTIVES

Endoscopic resection is preferred for duodenal carcinoids less than 20 mm; however, the efficacy of simple polypectomy has not been compared with advanced endoscopic resection techniques.

METHODS

We performed a retrospective review of 33 patients who underwent endoscopic duodenal carcinoid resection (10 simple, 23 endoscopic mucosal resection) at the Hospital of the University of Pennsylvania between January 1, 2006, and June 15, 2017. The primary outcomes were resection margin positivity and local tumor recurrence.

RESULTS

There were no significant differences in demographics or tumor functionality. Lesions managed with simple polypectomy had smaller median gross specimen size (6.0 mm vs 8.0 mm, P = 0.043). There was no significant difference in pathology resection margins between simple polypectomy and endoscopic mucosal resection (86% vs 68% positive, P = 0.64). Local recurrence on surveillance endoscopy was also similar (14.3% vs 17.7%, respectively; P = 1.000), with median time to recurrence 2.3 months (interquartile range, 1.2-5.4 months). The median follow-up time in patients without local recurrence was 21.4 months (interquartile range, 7.1-39.6 months).

CONCLUSIONS

Simple polypectomy may be adequate treatment of small duodenal carcinoids, although further studies are needed for validation and to define the upper limits of tumor size that can be managed with this technique.

Neuroendocrine Carcinoma of Duodenum-an Uncommon Tumour at an Unusual Site

Neuroendocrine carcinoma rarely occurs in the duodenum, and most cases of neuroendocrine carcinoma in the duodenum show rapid progression of the disease. Such cases have poor prognosis even with radical surgery with or without chemotherapy with low 5-year survival rate. We present a case of a 52-year-old man who presented with abdominal pain of 1-month duration and one episode of vomiting. Upper gastrointestinal endoscopy revealed polypoidal lesions in the first and second part of the duodenum. Whipple's procedure was performed. Diagnosis of poorly differentiated neuroendocrine carcinoma was made with extension to pancreas with peripancreatic lymph node metastases. The patient expired on post operative day 17 following cardiac arrest.

Non-functional duodenal neuroendocrine carcinoma: a rare cause of diabetes mellitus

A 40-year-old Caucasian female presented with hyperglycaemia, polyuria, polydipsia and weight loss of 6 kg over a 1-month period. There was no personal or family history of malignancy or diabetes mellitus. On examination, she was jaundiced with pale mucous membranes and capillary glucose was 23.1 mmol/L. Initial investigations showed iron deficiency anaemia and obstructive pattern of liver function tests. HbA1c was diagnostic of diabetes mellitus at 79 mmol/mol. Malignancy was suspected and CT chest, abdomen and pelvis showed significant dilatation of intra- and extra-hepatic biliary tree including pancreatic duct, with periampullary 30 mm mass lesion projecting into lumen of duodenum. Enlarged nodes were seen around the superior mesenteric artery. This was confirmed on MRI liver. Fasting gut hormones were normal except for a mildly elevated somatostatin level. Chromogranin A was elevated at 78 pmol/L with normal chromogranin B. Duodenoscopy and biopsy showed possible tubovillous adenoma with low-grade dysplasia, but subsequent endoscopic ultrasound and biopsy revealed a grade 1, well differentiated neuroendocrine tumour. The patient was started on insulin, transfused to Hb >8 g/dL and Whipple’s pancreatico-duodenectomy was undertaken. This showed a well-differentiated neuroendocrine carcinoma arising in duodenum (Grade G1 with Ki67: 0.5%), with areas of chronic pancreatitis and preservation of pancreatic islet cells. There was complete resolution of diabetes post Whipple’s procedure and patient was able to come of insulin treatment. Her last HBA1C was 31 mmol/mol, 4 months post tumour resection.