Is surgery beneficial for MEN1 patients with small (< or = 2 cm), nonfunctioning pancreaticoduodenal endocrine tumor? An analysis of 65 patients from the GTE

[Individualized approach for MEN1-associated duodenopancreatic neuroendocrine neoplasms]

BACKGROUND

Multiple endocrine neoplasia type 1 (MEN1)-associated duodenopancreatic neuroendocrine neoplasms (dpNEN) represent the most frequent syndrome-associated cause of death, but the adequate treatment is sometimes considered controversial.

OBJECTIVE

Presentation of possible diagnostic and therapeutic options for MEN1-associated dpNENs.

MATERIAL AND METHODS

In this review article retrospective case studies, expert recommendations, national and international guidelines as well as personal experiences were analyzed and evaluated.

RESULTS

Due to early detection programs and the use of the most modern imaging techniques, dpNEN are nowadays diagnosed much earlier. Nonfunctional pNENs currently represent the most frequent dpNENs with about 70%, followed by gastrinomas and insulinomas. Regardless of their functional activity, dpNENs with a size of > 2 cm are generally an indication for surgery. The choice of the optimal treatment strategy, however, in most cases remains the subject of controversial discussions, although nowadays surgery should always be performed in an organ-preserving and minimally invasive way when feasible. Recurrences or new dpNENs are expected in more than 60% of cases, necessitating a reoperation in up to 40% of these cases. Duodenopancreatic resections and reoperations can be carried out safely by experienced practitioners and with an acceptable level of risk.

CONCLUSION

The planning of treatment requires careful consideration of the suitable timing, the extent of the operation, the risk of recurrence and potential morbidities. Furthermore, preserving pancreatic function and the quality of life is of utmost importance. In view of the complexity of the disease, MEN1 patients should be treated in specialized centers.

[Indication and Surgical Procedures for MEN1-associated Duodenopancreatic Neuroendocrine Neoplasms]

The optimal therapy of duodenopancreatic neuroendocrine neoplasia (dpNEN), which occurs in the context of multiple endocrine neoplasia type 1, is still a major challenge and is controversial. Due to the rarity of the disease, there is a lack of prospective randomised studies, so that most recommendations regarding the surgical indication and procedure are based on retrospective case series. In summary, surgical therapy is indicated for non-functional dpNEN > 2 cm, suspected malignancy and functionally active dpNEN. Enucleation or formal pancreatic resections with or without lymphadenectomy may be considered. The aim of therapy should be to eliminate hormone-associated symptoms and prevent an aggressive metastatic disease. At the same time, pancreatic function and quality of life should be preserved in the mostly young patients by resections that save as much parenchyma as possible.

Molecular and Clinical Spectrum of Primary Hyperparathyroidism

Recent data suggest an increase in the overall incidence of parathyroid disorders, with primary hyperparathyroidism (PHPT) being the most prevalent parathyroid disorder. PHPT is associated with morbidities (fractures, kidney stones, chronic kidney disease) and increased risk of death. The symptoms of PHPT can be nonspecific, potentially delaying the diagnosis. Approximately 15% of patients with PHPT have an underlying heritable form of PHPT that may be associated with extraparathyroidal manifestations, requiring active surveillance for these manifestations as seen in multiple endocrine neoplasia type 1 and 2A. Genetic testing for heritable forms should be offered to patients with multiglandular disease, recurrent PHPT, young onset PHPT (age ≤40 years), and those with a family history of parathyroid tumors. However, the underlying genetic cause for the majority of patients with heritable forms of PHPT remains unknown. Distinction between sporadic and heritable forms of PHPT is useful in surgical planning for parathyroidectomy and has implications for the family. The genes currently known to be associated with heritable forms of PHPT account for approximately half of sporadic parathyroid tumors. But the genetic cause in approximately half of the sporadic parathyroid tumors remains unknown. Furthermore, there is no systemic therapy for parathyroid carcinoma, a rare but potentially fatal cause of PHPT. Improved understanding of the molecular characteristics of parathyroid tumors will allow us to identify biomarkers for diagnosis and novel targets for therapy.

Surgical Management of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are relatively uncommon malignancies, characterized as either functional or nonfunctional secondary to their secretion of biologically active hormones. A wide range of clinical behavior can be seen, with the primary prognostic indicator being tumor grade as defined by the Ki67 proliferation index and mitotic index. Surgery is the primary treatment modality for PNETs. While functional PNETs should undergo resection for symptom control as well as potential curative intent, nonfunctional PNETs are increasingly managed nonoperatively. There is increasing data to suggest small, nonfunctional PNETs (less than 2 cm) are appropriate follow with nonoperative active surveillance. Evidence supports surgical management of metastatic disease if possible, and occasionally even surgical management of the primary tumor in the setting of widespread metastases. In this review, we highlight the evolving surgical management of local and metastatic PNETs.

Metastatic Grade 3 Neuroendocrine Tumor in Multiple Endocrine Neoplasia Type 1 (MEN1) Expressing Somatostatin Receptors

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) can occur in 30-90% of patients with Multiple Endocrine Neoplasia Type 1 (MEN1). However, only 1% of GEP-NETs are Grade 3 (G3). Given the rarity of these aggressive tumors, treatment of advanced G3 GEP-NETs in MEN1 is based on the treatment guidelines for sporadic GEP-NETs. We report a 43-year-old male with germline MEN1 followed at our institution with clinical features including hyperparathyroidism, a non-functional pancreatic NET, and Zollinger-Ellison Syndrome. On routine surveillances imaging, at age 40, computer tomography (CT/ positron emission tomography (PET)) imaging showed two arterially enhancing intraluminal masses on the medial aspect of the gastric wall. Anatomical imaging confirmed two enhancing masses within the pancreas and a rounded mass-like thickening along the lesser curvature of the stomach. The gastric mass was resected, and pathology reported a well-differentiated G3 NET with a Ki-67 &gt;20%. The patient continued active surveillance. Eighteen months later cross-sectional imaging studies showed findings consistent with metastatic disease within the right hepatic lobe and bland embolization was done. On follow-up scans, including 68Ga-DOTATATE (68Ga-DOTA(0)-Tyr(3)-octreotate) imaging, interval increase in number and avidity of metastatic lesions were compatible with disease progression. Given a paucity of treatment recommendations for G3 tumors in MEN1, the patient was counseled based on standard NET treatment guidelines and recommended 177Lu-DOTATATE treatment. PRRT (peptide receptor radionuclide therapy) with 177Lu-DOTATATE ( 177Lu-tetraazacyclododecanetetraacetic acid-octreotide) is an important therapeutic modality for patients with somatostatin receptor-positive (SSTR) NETs. However, prospective studies are needed to understand the role of PRRT in G3 NETs.

Multiple Endocrine Neoplasia in Childhood: An Update on Diagnosis, Screening, Management and Treatment

Multiple endocrine neoplasia (MEN) is a group of heterogenous syndromes characterized by the occurrence of two or more endocrine gland tumors in a patient or related individuals in the same family. They are inherited in an autosomal dominant fashion and are highly penetrant. There are three types of MEN syndromes: MEN type 1 (MEN1), MEN type 2 (MEN2), and MEN type 4 (MEN4). MEN2 is further divided into MEN2A, MEN2B (formerly known MEN3), and familial medullary thyroid carcinoma (FMTC). Although MEN syndromes are rare, it is crucial to identify individuals at risk for potentially life-threatening neoplasias. This review article provides an update on each MEN syndrome, its genetics, diagnosis, and management in children.

A bioactivated in vivo assembly nanotechnology fabricated NIR probe for small pancreatic tumor intraoperative imaging

Real-time imaging of the tumour boundary is important during surgery to ensure that sufficient tumour tissue has been removed. However, the current fluorescence probes for bioimaging suffer from poor tumour specificity and narrow application of the imaging window used. Here, we report a bioactivated in vivo assembly (BIVA) nanotechnology, demonstrating a general optical probe with enhanced tumour accumulation and prolonged imaging window. The BIVA probe exhibits active targeting and assembly induced retention effect, which improves selectivity to tumours. The surface specific nanofiber assembly on the tumour surface increases the accumulation of probe at the boundary of the tumor. The blood circulation time of the BIVA probe is prolonged by 110 min compared to idocyanine green. The assembly induced metabolic stability broaden the difference between the tumor and background, obtaining a delayed imaging window between 8-96 h with better signal-to-background contrast (>9 folds). The fabricated BIVA probe permits precise imaging of small sized (<2 mm) orthotopic pancreatic tumors in vivo. The high specificity and sensitivity of the BIVA probe may further benefit the intraoperative imaging in a clinical setting.

What Are the Place and Modalities of Surgical Management for Pancreatic Neuroendocrine Neoplasms? A Narrative Review

Pancreatic neuroendocrine neoplasms (panNENs) are a heterogeneous group of tumors derived from cells with neuroendocrine differentiation. They are considered malignant by default. However, their outcomes are variable depending on their presentation in the onset of hereditary syndromes, hormonal secretion, grading, and extension. Therefore, although surgical treatment has long been suggested as the only treatment of pancreatic neuroendocrine neoplasms, its modalities are an evolving landscape. For selected patients (small, localized, non-functional panNENs), a "wait and see" strategy is suggested, as it is in the setting of multiple neuroendocrine neoplasia type 1, but the accurate size cut-off remains to be established. Parenchyma-sparring pancreatectomy, aiming to limit pancreatic insufficiency, are also emerging procedures, which place beyond the treatment of insulinomas and small non-functional panNENs (in association with lymph node picking) remains to be clarified. Furthermore, giving the fact that the liver is generally the only metastatic site, surgery keeps a place of choice alongside medical therapies in the treatment of metastatic disease, but its modalities and extensions are still a matter of debate. This narrative review aims to describe the current recommended surgical management for pancreatic NENs and controversies in light of the actual recommendations and recent literature.

A Direct Comparison of Patients With Hereditary and Sporadic Pancreatic Neuroendocrine Tumors: Evaluation of Clinical Course, Prognostic Factors and Genotype-Phenotype Correlations

Introduction

Pancreatic neuroendocrine tumors (PNETs) in hereditary syndromes pose a significant challenge to clinicians. The rarity of these syndromes and PNETs itself make it difficult to directly compare them with sporadic PNETs. Despite research suggesting differences between these two entities, the same approach is used in hereditary and sporadic PNETs.

Methods

We included 63 patients with hereditary PNET (GpNET) and 145 with sporadic PNET (SpNET) in a retrospective observational study. Clinical and genetic data were collected in two Polish endocrine departments from January 2004 to February 2020. Only patients with confirmed germline mutations were included in the GpNET cohort. We attempted to establish prognostic factors of metastases and overall survival in both groups and genotype-phenotype correlations in the GpNET group.

Results

Patients with GpNET were younger and diagnosed earlier, whereas their tumors were smaller and more frequently multifocal compared with patients with SpNET. Metastases occurred more frequently in the SpNET group, and their appearance was associated with tumor size in both groups. GpNET patients had longer overall survival (OS). OS was affected by age, age at diagnosis, sex, grade, stage, tumor diameter, occurrence and localization of metastases, type of treatment, and comorbidities. In the MEN1 group, carriers of frameshift with STOP codon, splice site, and missense mutations tended to have less advanced disease, while patients with mutations in exon 2 tended to have metastases more frequently.

Conclusions

Direct comparisons of GpNET and SpNET demonstrate significant differences in the clinical courses of both entities, which should force different approaches. A larger group of patients with GpNET should be assessed to confirm genotype-phenotype correlations.

Distinct Prognostic Factors in Sporadic and Multiple Endocrine Neoplasia Type 1-Related Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNET) may develop sporadically or in the context of hereditary syndromes. In patients with multiple endocrine neoplasia type 1 (MEN1), PNET is the leading cause of death. Our aim was to compare the mortality risk in sporadic and MEN1-related PNETs and identify high-risk populations. A retrospective Surveillance, Epidemiology, and End Results database analysis of patients with PNET was used. Patients with MEN1 were defined by syn/metachronous pituitary adenoma. Clinical data were retrieved, and all-cause mortality (ACM) risk was compared in univariate and multivariable analyses. The cohort included 569 patients (46.6% males) with sporadic (n=542) and MEN1-related (n=27) PNETs. Age at diagnosis of MEN1-related PNET was significantly younger than with sporadic PNETs (mean age 49.2±16.7 vs. 61.6±12.7 years, respectively; p < 0.001). Survival analysis showed a trend for a better outcome in patients with MEN1-related vs. sporadic PNET (Log-rank, p=0.09) and in subgroup analysis for patients with advanced disease (p=0.08). Furthermore, among patients followed expectantly, those with MEN1-related PNET had lower ACM risk than their sporadic counterparts (p=0.08). Multivariable analysis demonstrated lower ACM risk in patients diagnosed with MEN1 (hazard ratio 0.35, 95% confidence interval 0.11-1.2, p=0.09), further supporting the trend detected in the univariate analysis. In conclusion, our study demonstrates the distinct clinical profile of patients with MEN1-related PNET compared to sporadic disease and emphasizes the expertise required to accurately manage patients with PNET in this rare context. The cautious decision-making required before embarking on surgical intervention is further emphasized in this robust analysis of a large cancer database.

Multiple Endocrine Neoplasia Type 1: Latest Insights

Multiple endocrine neoplasia type 1 (MEN1), a rare tumor syndrome that is inherited in an autosomal dominant pattern, is continuing to raise great interest for endocrinology, gastroenterology, surgery, radiology, genetics, and molecular biology specialists. There have been 2 major clinical practice guidance papers published in the past 2 decades, with the most recent published 8 years ago. Since then, several new insights on the basic biology and clinical features of MEN1 have appeared in the literature, and those data are discussed in this review. The genetic and molecular interactions of the MEN1-encoded protein menin with transcription factors and chromatin-modifying proteins in cell signaling pathways mediated by transforming growth factor β/bone morphogenetic protein, a few nuclear receptors, Wnt/β-catenin, and Hedgehog, and preclinical studies in mouse models have facilitated the understanding of the pathogenesis of MEN1-associated tumors and potential pharmacological interventions. The advancements in genetic diagnosis have offered a chance to recognize MEN1-related conditions in germline MEN1 mutation-negative patients. There is rapidly accumulating knowledge about clinical presentation in children, adolescents, and pregnancy that is translatable into the management of these very fragile patients. The discoveries about the genetic and molecular signatures of sporadic neuroendocrine tumors support the development of clinical trials with novel targeted therapies, along with advancements in diagnostic tools and surgical approaches. Finally, quality of life studies in patients affected by MEN1 and related conditions represent an effort necessary to develop a pharmacoeconomic interpretation of the problem. Because advances are being made both broadly and in focused areas, this timely review presents and discusses those studies collectively.

Imaging of Insulinoma by Targeting Glucagonlike Peptide-1 Receptor

"Glucagonlike peptide-1 (GLP-1) receptor imaging, using radiolabeled exendin-4, was recently established for detecting insulinoma in patients with hyperinsulinemic hypoglycemia. It has proven to be a sensitive and specific method for preoperative localization of insulinoma. This review introduces the development, clinical research, and perspective of GLP-1 receptor imaging mainly in insulinoma.

Prognostic factors for the outcome of nonfunctioning pancreatic neuroendocrine tumors in MEN1: a systematic review of literature

Metastatic duodenopancreatic neuro-endocrine tumors (dpNETs) are the most important disease-related cause of death in patients with multiple endocrine neoplasia type 1 (MEN1). Nonfunctioning pNETs (NF-pNETs) are highly prevalent in MEN1 and clinically heterogeneous. Therefore, management is controversial. Data on prognostic factors for risk stratification are limited. This systematic review aims to establish the current state of evidence regarding prognostic factors in MEN1-related NF-pNETs. We systematically searched four databases for studies assessing prognostic value of any factor on NF-pNET progression, development of distant metastases, and/or overall survival. In- and exclusion, critical appraisal and data-extraction were performed independently by two authors according to pre-defined criteria. Thirteen studies (370 unique patients) were included. Prognostic factors investigated were tumor size, timing of surgical resection, WHO grade, methylation, p27/p18 expression by immunohistochemistry (IHC), ARX/PDX1 IHC and alternative lengthening of telomeres. Results were complemented with evidence from studies in MEN1-related pNET for which data could not be separately extracted for NF-pNET and data from sporadic NF-pNET. We found that the most important prognostic factors used in clinical decision making in MEN1-related NF-pNETs are tumor size and grade. NF-pNETs <2 cm may be managed with watchful waiting, while surgical resection is advised for NF-pNETs ≥2 cm. Grade 2 NF-pNETs should be considered high risk. The most promising and MEN1-relevant avenues of prognostic research are multi-analyte circulating biomarkers, tissue-based molecular factors and imaging-based prognostication. Multi-institutional collaboration between clinical, translation and basic scientists with uniform data and biospecimen collection in prospective cohorts should advance the field.

Surgical Principles in the Management of Pancreatic Neuroendocrine Neoplasms

OPINION STATEMENT

Pancreatic neuroendocrine neoplasms (PanNENs) are increasingly recognized entities, whose incidence has dramatically grown during the last two decades. Surgery plays a pivotal role in their management as it represents the only chance of cure. Since PanNENs display a wide range of aggressiveness, their surgical management needs to be tailored on tumor's and patient's characteristics. Currently, there are several open questions and burning issues in the field of PanNEN, such as the management of asymptomatic nonfunctioning pancreatic neuroendocrine tumors (NF-PanNET) ≤ 2 cm. An active surveillance of these small lesions has been demonstrated to be safe although the available evidences are only based on retrospective studies. On the other hand, formal pancreatic resection associated with lymphadenectomy represents the gold standard for patients with localized NF-PanNEN > 2 cm or NF-PanNEN ≤ 2 cm in the presence of symptoms, dilation of the main pancreatic duct or suspicion of nodal metastases. Surgery plays also an important role in the setting of metastatic disease. In particular, surgery is generally recommended in the presence of low-grade, resectable, metastatic disease, but several series have reported also a survival benefit of palliative primary tumor resection in patients with unresectable liver metastases. The role of surgery in PanNEN G3 is still controversial. Indeed, surgery is associated with an improved survival in patients with well-differentiated PanNET G3, whereas there is almost no survival benefit in case of poorly differentiated lesions.

Innovative imaging of insulinoma: the end of sampling? A review

Receptors for the incretin glucagon-like peptide-1 (GLP-1R) have been found overexpressed in selected types of human tumors and may, therefore, play an increasingly important role in endocrine gastrointestinal tumor management. In particular, virtually all benign insulinomas express GLP-1R in high density. Targeting GLP-1R with indium-111, technetium-99m or gallium-68-labeled exendin-4 offers a new approach that permits the successful localization of small benign insulinomas. It is likely that this new non-invasive technique has the potential to replace the invasive localization of insulinomas by selective arterial stimulation and venous sampling. In contrast to benign insulinomas, malignant insulin-secreting neuroendocrine tumors express GLP-1R in only one-third of the cases, while they more often express the somatostatin subtype 2 receptors. Importantly, one of the two receptors appears to be always overexpressed. In special cases of endogenous hyperinsulinemic hypoglycemia (EHH), that is, in the context of MEN-1 or adult nesidioblastosis GLP-1R imaging is useful whereas in postprandial hypoglycemia in the context of bariatric surgery, GLP-1R imaging is probably not helpful. This review focuses on the potential use of GLP-1R imaging in the differential diagnosis of EHH.

La néoplasie endocrinienne multiple de type 1 : mise au point après le congrès de l’ENETS 2019

Multiple Endocrine Neoplasia Type 1 (NEM1) is related to mutations of the menin gene. It is an autosomal dominant disease. Its prevalence is about 1/30 000 with a hugh penetrance. There is no genotype-phenotype correlation. This hereditary syndrome is characterized by the presence of tumors of the endocrine system (parathyroid, endocrine pancreas, pituitary and adrenal gland). Other disorders have also been described (bronchial and thymic carcinoid tumor, breast cancer, skin lesions). Management must take into account the specificities of these pathologies in NEM1 compared to sporadic forms (young age at diagnosis, multiple lesions within the same gland, multi-focal disease). © 2019 Published by Elsevier Masson SAS. All rights reserved. Cet article fait partie du numéro supplément Les Must de l'Endocrinologie 2019 réalisé avec le soutien institutionnel de Ipsen-Pharma.

Surgical management of pancreatic neuroendocrine tumors: an introduction

Introduction: Neuroendocrine tumors of the pancreas (pNETs) represent only 1% to 2% of all pancreatic neoplasms. These tumors can be classified as functional or nonfunctional tumors; as sporadic or from a genetic origin; as neuroendocrine neoplasms or carcinoma. Over the last decade, diagnosis of pNETs has increased significantly mainly due to the widespread use of cross-sectional imaging. Those tumors are usually associated with a good prognosis. Surgery, the only curative option for those patients, should always be discussed, ideally in a multidisciplinary team setting.Areas covered: We discuss i), the preoperative management of pNETs and the importance of accurate diagnosis, localization, grading and staging with computed tomography, magnetic resonance imaging, endoscopic ultrasound, and nuclear medicine imaging; ii), surgical indications and iii), the surgical approach (standard pancreatectomy vs pancreatic-sparing surgery).Expert opinion: The treatment option of all patients presenting with pNETs should be discussed in a multidisciplinary team setting with surgeon's experienced in both pancreatic surgery and neuroendocrine tumor management. A complete preoperative imaging assessment - morphological and functional - must be performed. Surgery is usually recommended for functional pNETs, nonfunctional pNETs >2 cm (nf-pNETs) or for symptomatic nf-pNETs.

68Ga-Exendin-4 PET/CT Detects Insulinomas in Patients With Endogenous Hyperinsulinemic Hypoglycemia in MEN-1

CONTEXT

Surgical intervention is advised in patients with multiple endocrine neoplasia type-1 (MEN-1) and nonfunctioning pancreatic neuroendocrine tumors (PanNETs) with a size ≥20 mm. Functioning PanNETs, such as in patients with endogenous hyperinsulinemic hypoglycemia (EHH) due to (one or multiple) insulinomas, should be treated surgically independent of size. Preoperative localization of insulinomas is critical for surgery.

OBJECTIVE

To evaluate the feasibility and sensitivity of 68Ga-DOTA-exendin-4 positron emission tomography (PET)/CT in the detection of clinically relevant lesions in patients with MEN-1 and EHH in combination with MRI.

DESIGN

Post hoc subgroup analysis of a larger prospective imaging study with 52 patients with EHH.

PATIENTS

Six of 52 consecutive patients with EHH and genetically proven MEN-1 mutation were included.

INTERVENTIONS

All patients received one 68Ga-DOTA-exendin-4 PET/CT and one MRI scan within 3 to 4 days. Thereafter, surgery was performed based on all imaging results.

MAIN OUTCOME MEASURES

Lesion-based sensitivity of PET/CT and MRI for detection of clinically relevant lesions was calculated. Readers were unaware of other results. The reference standard was surgery with histology and treatment outcome. True positive (i.e., clinically relevant lesions) was defined as PanNETs ≥20 mm or insulinoma.

RESULTS

In six patients, 37 PanNETs were confirmed by histopathology. Sensitivity (95% CI) in the detection of clinically relevant lesions for combined PET/CT plus MRI, MRI, and PET/CT was 92.3% (64% to 99.8%), 38.5% (13.9% to 68.4%), and 84.6% (54.6% to 98.1%), respectively (P = 0.014 for the comparison of PET/CT plus MRI vs MRI). Postsurgery, EHH resolved in all patients.

CONCLUSION

68Ga-DOTA-exendin-4 PET/CT is feasible in patients with MEN-1 and EHH. The combination with MRI is superior to MRI alone in the detection of insulinomas and may guide the surgical strategy.

Long-term Follow-up of MEN1 Patients Who Do Not Have Initial Surgery for Small ≤2 cm Nonfunctioning Pancreatic Neuroendocrine Tumors, an AFCE and GTE Study: Association Francophone de Chirurgie Endocrinienne & Groupe d'Etude des Tumeurs Endocrines

Objective:

To report long-term follow-up of patients with multiple endocrine neoplasia type 1 (MEN1) and nonfunctioning pancreatic neuroendocrine tumors (NF-PET).

Background:

Pancreaticoduodenal tumors occur in almost all patients with MEN1 and are a major cause of death. The natural history and clinical outcome are poorly defined, and management is still controversial for small NF-PET.

Methods:

Clinical outcome and tumor progression were analyzed in 46 patients with MEN1 with 2 cm or smaller NF-PET who did not have surgery at the time of initial diagnosis. Survival data were analyzed using the Kaplan-Meier method.

Results:

Forty-six patients with MEN1 were followed prospectively for 10.7 ± 4.2 (mean ± standard deviation) years. One patient was lost to follow-up and 1 died from a cause unrelated to MEN1. Twenty-eight patients had stable disease and 16 showed significant progression of pancreaticoduodenal involvement, indicated by increase in size or number of tumors, development of a hypersecretion syndrome, need for surgery (7 patients), and death from metastatic NF-PET (1 patient). The mean event-free survival was 13.9 ± 1.1 years after NF-PET diagnosis. At last follow-up, none of the living patients who had undergone surgery or follow-up had evidence of metastases on imaging studies.

Conclusions:

Our study shows that conservative management for patients with MEN1 with NF-PET of 2 cm or smaller is associated with a low risk of disease-specific mortality. The decision to recommend surgery to prevent tumor spread should be balanced with operative mortality and morbidity, and patients should be informed about the risk-benefit ratio of conservative versus aggressive management when the NF-PET represents an intermediate risk.

Management of MEN1 Related Nonfunctioning Pancreatic NETs: A Shifting Paradigm: Results From the DutchMEN1 Study Group

OBJECTIVE

To assess if surgery for Multiple Endocrine Neoplasia type 1 (MEN1) related nonfunctioning pancreatic neuroendocrine tumors (NF-pNETs) is effective for improving overall survival and preventing liver metastasis.

BACKGROUND

MEN1 leads to multiple early-onset NF-pNETs. The evidence base for guiding the difficult decision who and when to operate is meager.

METHODS

MEN1 patients diagnosed with NF-pNETs between 1990 and 2014 were selected from the DutchMEN1 Study Group database, including > 90% of the Dutch MEN1 population. The effect of surgery was estimated using time-dependent Cox analysis with propensity score restriction and adjustment.

RESULTS

Of the 152 patients, 53 underwent surgery and 99 were managed by watchful waiting. In the surgery group, tumors were larger and faster-growing, patients were younger, more often male, and were more often treated in centers that operated more frequently. Surgery for NF-pNETs was not associated with a significantly lower risk of liver metastases or death, [adjusted hazard ratio (HR) = 0.73 (0.25-2.11)]. Adjusted HR's after stratification by tumor size were: NF-pNETs <2 cm = 2.04 (0.31-13.59) and NF-pNETs 2-3 cm = 1.38 (0.09-20.31). Five out of the 6 patients with NF-pNETs >3 cm managed by watchful waiting developed liver metastases or died compared with 6 out of the 16 patients who underwent surgery.

CONCLUSIONS

MEN1 patients with NF-pNETs <2 cm can be managed by watchful waiting, hereby avoiding major surgery without loss of oncological safety. The beneficial effect of a surgery in NF-pNETs 2 to 3 cm requires further research. In patients with NF-pNETs >3 cm, watchful waiting seems not advisable.

Recent advances in the diagnosis and management of pancreatic neuroendocrine tumours

The incidence of pancreatic neuroendocrine tumours (PNET) is rising mainly due to the increased use of cross-sectional imaging. Although many PNETs are asymptomatic and non-functioning, the overall 5-year survival is still less than 50%. In this article, we review the advances in diagnosis, classification and staging of PNET that have evolved with the development of new cross-sectional imaging methods and biopsy techniques. With accurate classification, evidence-based, individualised prognostic outcomes and treatments are able to be given which are also discussed.

Results of Duodenopancreatic Reoperations in Multiple Endocrine Neoplasia Type 1

BACKGROUND

To evaluate the outcome of duodenopancreatic reoperations in patients with multiple endocrine neoplasia type 1 (MEN1).

METHODS

MEN1 patients who underwent reoperations for duodenopancreatic neuroendocrine neoplasms (dpNENs) were retrieved from a prospective database and retrospectively analyzed.

RESULTS

Twelve of 101 MEN1 patients underwent up to three reoperations, resulting in a total of 18 reoperations for dpNEN recurrence. Patients initially underwent either formal pancreatic resections (n = 7), enucleations (n = 3), or duodenotomy with lymphadenectomy for either NF-pNEN (seven patients), Zollinger-Ellison syndrome (ZES, three patients), organic hyperinsulinism (one patient) or VIPoma (one patient). Six patients had malignant dpNENs with lymph node (n = 5) and/or liver metastases (n = 2). The indication of reoperations was NF-pNEN (five patients), ZES (five patients), organic hyperinsulinism (one patient), and recurrent VIPoma (one patient). Median time to first reoperation was 67.5 (range 6-251) months. Five patients required a second duodenopancreatic reoperation for 60-384 months after initial surgery, and one patient underwent a third reoperation after 249 months. The rate of complications (Clavien-Dindo ≥3) was 28%. Four patients required completion pancreatectomy. Six patients developed pancreoprivic diabetes. After a median follow-up of 18 (6-34) years after initial surgery, ten of 12 patients are alive, one died of metastatic pancreatic VIPoma, and one died of metastatic thymic NEN.

CONCLUSION

Reoperations are frequently necessary for dpNEN in MEN1 patients, but are not associated with an increased perioperative morbidity in specialized centers. Organ-sparing resections should be preferred as initial duodenopancreatic procedures to maintain pancreatic function and avoid completion pancreatectomy.

Patient characteristics and clinical outcomes following initial surgical intervention for MEN1 associated pancreatic neuroendocrine tumours: A systematic review and exploratory meta-analysis of the literature

BACKGROUND

This systematic review aimed to define the outcomes of different pancreatic resection procedures for multiple endocrine neoplasia type 1 (MEN1) associated pancreatic neuroendocrine neoplasms (pNENs).

METHODS

A search of PubMed, MEDLINE and SCOPUS databases were performed in accordance with PRISMA guidelines.

RESULTS

Twenty-seven studies including 533 patients undergoing initial pancreatic resection for MEN1 associated pNENs were included in this systematic review. Three hundred and sixty-six (68.7%) distal pancreatectomies (DP), 120 (22.5%) sole enucleations (SE) and 47 (8.8%) pancreaticoduodenectomies (PD) were identified. SE was associated with a higher rate of recurrence than DP (25/67, 37% vs 40/190, 21% respectively, P = 0.008) but a lower rate of endocrine insufficiency than PD (1/20, 5% vs 8/21, 38% respectively, P = 0.010). A meta-analysis of major pancreatic resections (PD or DP) vs SE in 15 studies showed that SE is associated with an increased rate of recurrence (Major resection 42/184, 23% vs SE 20/53, 38% RR 0.65 CI 0.43-0.96 P = 0.032) but reduced rate of postoperative endocrine insufficiency (Resection 37/93, 40% vs SE 0/24, 0% RR 7.37 CI 1.57-34.64 P = 0.008). Similarly, insulinomas and functional pNENs overall had lower rates of recurrence and reoperation with major resection. There was no difference in the reoperation rates or survival outcomes after SE compared with major pancreatic resections at follow-up (pooled overall mean duration: 85 months).

CONCLUSION

Major pancreatic resections for MEN1 associated pNENs have a lower risk of recurrence and a higher risk of postoperative endocrine insufficiency when compared to sole enucleation, but a similar rate of reoperation and survival.

No evidence of adverse fertility and pregnancy outcomes in patients with unrecognized and untreated multiple endocrine neoplasia type 1

OBJECTIVE

Literature concerning the impact of multiple endocrine neoplasia type 1 (MEN 1) on fertility is limited to case reports despite the early onset of endocrinopathies, such as primary hyperparathyroidism and prolactinoma, that may impact fertility. This study describes the impact of unrecognized and untreated MEN 1 on fertility and pregnancy outcomes in a multigenerational cohort of the Tasman 1 MEN 1 kindred.

METHODS

All MEN 1 positive (MEN 1⁺ , n = 63) and MEN 1 negative (MEN 1^- , n = 75) descendants born between 1825 and 1951 of a common founder. Review of birth, death, marriage and medical records provided data on date of birth and death, gender, MEN 1 status and the number of pregnancies and children per parent.

RESULTS

Compared to MEN 1^- parents, MEN 1⁺ parents had more children (RR 1.30, 1.02-1.66) and live births (RR 1.31, 1.02-1.67) with no excess of stillbirths (RR 1.24, 0.24-6.36). Compared to the era-matched Tasmanian fertility rate, MEN 1⁺ parents had more children (4.87 ± 4.11 vs 3.40 ± 0.61, P = 0.048), whereas MEN 1^- parents had similar numbers of children (3.67 ± 3.27 vs 3.36 ± 0.62, P = 0.55). MEN 1⁺ parents had a similar number of MEN 1⁺ and MEN 1^- offspring (2.1 ± 1.9 vs 2.5 ± 2.3, P = 0.31). Indirectly assessed miscarriage rate was similar between MEN 1⁺ and MEN 1^- mothers (P = 0.77). Clinically overt pituitary disease reduced MEN 1⁺ kindred member likelihood of parenthood (33% vs 97%).

CONCLUSIONS

There was no adverse impact of MEN 1 on patient fertility overall; however, MEN 1-related pathology may have impaired the reproductive potential of a subset of individuals with pituitary disease.

Early and Late Complications After Surgery for MEN1-related Nonfunctioning Pancreatic Neuroendocrine Tumors

OBJECTIVE

To estimate short and long-term morbidity after pancreatic surgery for multiple endocrine neoplasia type 1 (MEN1)-related nonfunctioning pancreatic neuroendocrine tumors (NF-pNETs).

BACKGROUND

Fifty percent of the MEN1 patients harbor multiple NF-pNETs. The decision to proceed to NF-pNET surgery is a balance between the risk of disease progression versus the risk of surgery-related morbidity. Currently, there are insufficient data on the surgical complications after MEN1 NF-pNET surgery.

METHODS

MEN1 patients diagnosed with a NF-pNET who underwent surgery were selected from the DutchMEN1 study group database, including >90% of the Dutch MEN1 population. Early postoperative complications, new-onset diabetes mellitus, and exocrine pancreatic insufficiency were captured.

RESULTS

Sixty-one patients underwent NF-pNET surgery at 1 of the 8 Dutch academic centers. Patients were young (median age 41 years) with low American Society of Anesthesiologists scores. Median NF-pNET size on imaging was 22 mm (3-157). Thirty-three percent (19/58) of the patients developed major early-Clavien-Dindo grade III to IV-complications mainly consisting International Study Group of Pancreatic Surgery grade B/C pancreatic fistulas. Twenty-three percent of the patients (14/61) developed endocrine or exocrine pancreas insufficiency. The development of major early postoperative complications was independent of the NF-pNET tumor size. Twenty-one percent of the patients (12/58) developed multiple major early complications.

CONCLUSIONS

MEN1 NF-pNET surgery is associated with high rates of major short and long-term complications. Current findings should be taken into account in the shared decision-making process when MEN1 NF-pNET surgery is considered.

Multiple Endocrine Neoplasia Type 1 (MEN1): An Update and the Significance of Early Genetic and Clinical Diagnosis

Multiple endocrine neoplasia type 1 (MEN1) is a rare hereditary tumor syndrome inherited in an autosomal dominant manner and characterized by a predisposition to a multitude of endocrine neoplasms primarily of parathyroid, enteropancreatic, and anterior pituitary origin, as well as nonendocrine neoplasms. Other endocrine tumors in MEN1 include foregut carcinoid tumors, adrenocortical tumors, and rarely pheochromocytoma. Nonendocrine manifestations include meningiomas and ependymomas, lipomas, angiofibromas, collagenomas, and leiomyomas. MEN1 is caused by inactivating mutations of the tumor suppressor gene MEN1 which encodes the protein menin. This syndrome can affect all age groups, with 17% of patients developing MEN1-associated tumors before 21 years of age. Despite advances in the diagnosis and treatment of MEN1-associated tumors, patients with MEN1 continue to have decreased life expectancy primarily due to malignant neuroendocrine tumors. The most recent clinical practice guidelines for MEN1, published in 2012, highlight the need for early genetic and clinical diagnosis of MEN1 and recommend an intensive surveillance approach for both patients with this syndrome and asymptomatic carriers starting at the age of 5 years with the goal of timely detection and management of MEN1-associated neoplasms and ultimately decreased disease-specific morbidity and mortality. Unfortunately, there is no clear genotype-phenotype correlation and individual mutation-dependent surveillance is not possible currently.

Unmet Needs in Functional and Nonfunctional Pancreatic Neuroendocrine Neoplasms

Recently, the European Neuroendocrine Tumor Society (ENETS) held working sessions composed of members of the advisory board and other neuroendocrine neoplasm (NEN) experts to attempt to identify unmet needs in NENs in different locations or with advanced/poorly differentiated NENs. This report briefly summarizes the main proposed areas of unmet needs in patients with functional and nonfunctional pancreatic NENs.

Endoscopic Ultrasound Features of Multiple Endocrine Neoplasia Type 1-Related versus Sporadic Pancreatic Neuroendocrine Tumors: A Single-Center Retrospective Study

AIM

Pancreatic neuroendocrine tumors (pNETs) can occur in patients with a familial syndrome either as multiple endocrine neoplasia type 1 (MEN-1) or as sporadic tumors. Endoscopic ultrasound (EUS) has become one of the first-line investigations for pNET characterization. The ultrasonographic features of pNETs may differ depending on the familial versus sporadic pathogenesis of the tumor. Therefore, the EUS findings could help and direct the definition of a pNET with an impact on the most appropriate diagnostic and therapeutic patient management.

METHODS

In this single-center retrospective study, we reviewed the EUS features of 94 pNETs from 37 MEN-1 patients and 15 pNETs from 11 sporadic disease patients at the time of their first EUS assessment. We analyzed the most relevant morphological and ultrasonographic characteristics of the tumors and compared the findings between the 2 patient groups.

RESULTS

Patients with MEN-1 more likely present with multiple pNETs than patients with sporadic disease. Sporadic pNETs are usually much bigger than those due to MEN-1. Moreover, pNETs are more heterogeneous in patients with sporadic disease than in those with MEN-1. No statistical difference with regard to definition of the margins, morphology, and vascularization of the pNETs appears between the 2 groups.

CONCLUSIONS

Patients with sporadic disease usually present with bigger and more heterogeneous pNETs than patients with MEN-1, who tend to present with a higher number of lesions. EUS can facilitate the precise characterization of a pNET, and the ultrasonographic features of the lesion can help and distinguish MEN-1-related versus sporadic disease.

Ki-67 and presence of liver metastases identify different progression-risk classes in pancreatic neuroendocrine neoplasms (pNEN) undergoing resection

In pancreatic neuroendocrine neoplasms (pNEN), size ≤2 cm and Ki-67 < 3% suggest indolent behavior, but no factor alone predicts prognosis. We investigated factors predictive of tumor progression in 80 pNENs surgically resected in a single Institution from 1995 to 2015. At multivariable analysis the only two independent variables related to PFS were Ki-67 (HR 2.97; 95%CI 1.26-7.02) and presence of synchronous liver metastases (HR 3.60; 95%CI 1.70-7.61). Using Ki-67 < 3% and M0 as reference, the HR for tumor progression was 3.21 (95%CI 1.18-8.74) for M0 patients with Ki-67 3-20%, 5.06 (2.29-11.2) for M1 patients with Ki-67 ≤ 20% and 24.3 (6.64-89.2) for those with Ki-67 > 20%. Tumor size (≤2 vs. >2 cm) was not a predictive factor at any analysis. Intra-class correlation of Ki-67 values on pre-surgical biopsies vs. surgical specimens was 0.99 and Ki-67 classes were correctly identified in 97% of biopsies. Ki-67 and presence of liver metastases are the major prognostic factors in pNEN and identify different progression risks regardless of tumor size. Pre-surgical pNEN biopsy for Ki-67 assessment should be included in the evaluation of patients with 1-2 cm tumors to help in the decision on whether to perform surgical resection.

Preoperative Imaging Overestimates the Tumor Size in Pancreatic Neuroendocrine Neoplasms Associated with Multiple Endocrine Neoplasia Type 1

BACKGROUND

Radiological tumor size of non-functioning pancreatic neuroendocrine neoplasms (Nf-pNENs) associated with multiple endocrine neoplasia type 1 (MEN1) is a crucial parameter to indicate surgery. The aim of this study was to compare radiological size (RS) and pathologic size (PS) of MEN1 associated with pNENs.

METHODS

Prospectively collected data of MEN1 patients who underwent pancreatic resections for pNENs were retrospectively analyzed. RS was defined as the largest tumor diameter measured on endoscopic ultrasound (EUS), magnetic resonance imaging (MRI) or computed tomography (CT). PS was defined as the largest tumor diameter on pathological analysis. Student's t test and linear regression analysis were used to compare the median RS and PS. p < 0.05 was considered significant.

RESULTS

Forty-four patients with a median age of 37 (range 10-68) years underwent primary pancreatic resections for pNENs. Overall, the median RS (20 mm, range 3-100 mm) was significantly larger than the PS (13 mm, range 4-110 mm) (p = 0.001). In patients with pNENs < 20 mm (n = 27), the size difference (median RS 15 mm vs PS 12 mm) was also significant (p = 0.003). However, the only modality that significantly overestimated the PS was EUS (median RS 14 mm vs 11 mm; p = 0.0002). RS overestimated the PS in 21 patients (21 of 27 patients, 78%). Five of 11 patients (12%) with a Nf-pNEN and a RS > 20 mm had in reality a PS < 20 mm. MRI was the imaging technique that best correlated with PS in the total cohort (r = 0.8; p < 0.0001), whereas EUS was the best correlating imaging tool in pNENs < 20 mm (r = 0.5; p = 0.0001).

CONCLUSION

Preoperative imaging, especially EUS, frequently overestimates the size of MEN1-pNENs, especially those with a PS < 20 mm. This should be considered when indicating surgery in MEN1 patients with small Nf-pNENs.

Gastrinomas: Medical or Surgical Treatment

This article reviews the role of surgical and medical management in patients with Zollinger-Ellison syndrome (ZES) due to a gastrin-secreting neuroendocrine tumor (gastrinoma). It concentrates on the status at present but also briefly reviews the changes over time in treatment approaches. Generally, surgical and medical therapy are complementary today; however, in some cases, such as patients with ZES and multiple endocrine neoplasia type 1, the treatment approach remains controversial.

How should incidental NEN of the pancreas and gastrointestinal tract be followed?

Neuroendocrine gastro-entero-pancreatic neoplasms (GEP-NENs) constitute a heterogeneous group of tumors, whose incidence has increased over the years. The most frequent site for primary disease is the stomach followed by small and large intestine, and pancreas. In the last decade, a dramatic growing in the incidence of small, incidental GEP-NENs has been recorded. In parallel, an increasing attitude toward more conservative approaches instead of surgical management has being widely spreading. This is particularly true for small, asymptomatic, pancreatic NEN as for these tumor forms an active surveillance has proven to be safe and feasible. Primary site and biological features of the neoplasms lead to different strategies and indications for surveillance and follow-up. This review focuses on the current evidence on modality and timing of surveillance and conservative treatment of incidentally discovered lesions.

Current and emerging therapies for PNETs in patients with or without MEN1

Pancreatic neuroendocrine tumours (PNETs) might occur as a non-familial isolated endocrinopathy or as part of a complex hereditary syndrome, such as multiple endocrine neoplasia type 1 (MEN1). MEN1 is an autosomal dominant disorder characterized by the combined occurrence of PNETs with tumours of the parathyroids and anterior pituitary. Treatments for primary PNETs include surgery. Treatments for non-resectable PNETs and metastases include biotherapy (for example, somatostatin analogues, inhibitors of receptors and monoclonal antibodies), chemotherapy and radiological therapy. All these treatments are effective for PNETs in patients without MEN1; however, there is a scarcity of clinical trials reporting the efficacy of the same treatments of PNETs in patients with MEN1. Treatment of PNETs in patients with MEN1 is challenging owing to the concomitant development of other tumours, which might have metastasized. In recent years, preclinical studies have identified potential new therapeutic targets for treating MEN1-associated neuroendocrine tumours (including PNETs), and these include epigenetic modification, the β-catenin-wingless (WNT) pathway, Hedgehog signalling, somatostatin receptors and MEN1 gene replacement therapy. This Review discusses these advances.

The future: surgical advances in MEN1 therapeutic approaches and management strategies

Multiple endocrine neoplasia type 1 (MEN1) is a hereditary autosomal dominant disorder associated with numerous neuroendocrine tumors (NETs). Recent advances in the management of MEN1 have led to a decrease in mortality due to excess hormones; however, they have also led to an increase in mortality from malignancy, particularly NETs. The main challenges are to localize these tumors, to select those that need therapy because of the risk of aggressive behavior and to select the appropriate therapy associated with minimal morbidity. This must be applied to a hereditary disease with a high risk of recurrence. The overall aim of management in MEN1 is to ensure that the patient remains disease- and symptom-free for as long as possible and maintains a good quality of life. Herein, we review the changes that occurred in the last 20 years in the surgical management of MEN1-associated functional and non-functional pancreatico-duodenal NETs and thymic and bronchial NETs.

Gastro-entero-pancreatic neuroendocrine tumors in multiple endocrine neoplasia type 1: a therapy update

Gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs) are the second most common tumors in multiple endocrine neoplasia type 1 (MEN1), mainly occurring in pancreatic islets and duodenum, usually as multiple tumors. They can manifest as both nonfunctioning and functioning tumors. Currently, surgical removal of GEP-NETs in MEN1 represents the gold standard curative approach. Conventional medical therapies for sporadic GEP-NETs showed to be effective also in a percentage of MEN1 patients. Innovative medical therapies, that have demonstrated to be effective on sporadic GEP-NETs, still need to be evaluated on MEN1 patients in prospective clinical trials and long-term follow-up. This review resumes current knowledge of MEN1 GEP-NETs, discussing surgical and medical approaches, genetic and molecular bases of tumorigenesis, and presenting novel possible drug therapies.

Complicated Case Presentation: Management of Pancreatic Neuroendocrine Tumors in Multiple Endocrine Neoplasia Type 1

Multiple endocrine neoplasia type 1 (MEN1) is an inherited predisposition to tumors of the parathyroid glands, anterior pituitary, and pancreatic islet cells. In this review, we discuss the clinical case of a 45-year-old woman with MEN1 that was presented at the 2015 North American Neuroendocrine Tumor Society Symposium. In our review of this patient's complicated clinical course and subsequent operative management, we highlight controversies in the diagnosis and management of pancreatic neuroendocrine tumors in MEN1. In particular, this case illustrates the lack of consensus regarding the optimal biochemical and radiologic screening for pancreatic neuroendocrine tumors and absence of guidelines about the appropriate surgical approach for treatment. We review these controversies and discuss possible approaches to management.

Nonfunctioning, small, incidental pancreatic neuroendocrine tumors: Results of a nonoperative approach cohort

OBJECTIVE

The availability of new imaging techniques has conditioned an increase in the incidental diagnosis of small nonfunctioning pancreatic neuroendocrine tumors (PNET-NF). The best treatment is controversial, some authors advise a conservative approach in selected cases. Our aim is to analyze the evolution of incidental, small size PNET-NF, treated with clinical follow-up without surgery.

METHODS

We performed a retrospective analysis of a prospective database of patients diagnosed incidentally with PNET-NF since November 2007 to September 2015. We include those with PNET-NF ≤2cm and asymptomatic. The diagnosis was performed using imaging tests indicating endoscopic ultrasound-guided fine-needle aspiration in case of doubts in the diagnosis. The follow-up was performed at our center, registering clinical and/or radiological changes.

RESULTS

We included 24 patients with a median age of 70 years, and a similar distribution in terms of sex. The diagnosis was made through computed tomography multidetector or magnetic resonance imaging and octreotide scan. The tumors were located mainly in the head and neck (46%), with a mean size of 11,5±3,55mm at diagnosis (5-19mm). In 2 cases endoscopic ultrasound fine needle aspiration was used (8%), confirming the diagnosis of low-grade PNET with Ki67<5%. The median follow-up was 39 months (7-100). In 19 patients (79%) they remained the same size, 21% (5) increased its size with a mean of 2,6±2mm (1-6). No cases had progression of disease.

CONCLUSION

In selected patients, non-surgical management of PNET-NF is an option to consider, when they are asymptomatic and ≤2cm. Larger studies with more patients and more time of follow-up are needed to validate this non-operative approach.

A wait-and-watch approach to small pancreatic neuroendocrine tumors: prognosis and survival

Background

Whether all the small (ø≤20mm) non-functional pancreatic neuroendocrine neoplasms (pNENs) should be routinely resected is unclear.

Aim

To assess the overall survival (OS) and progression-free survival (PFS) of patients with small pNENs, followed-up with different management options.

Material and methods

Between 2007-2014, 51 patients were newly diagnosed with pNEN. 15 patients with pNENs ø ≤20 mm underwent an intensive follow-up at 3-month intervals during the first year and then every 6 months (FU pNEN group). They were all at TNM stage I, except for one patient at stage IIA. 21 patients underwent surgical resection (SR pNEN group): 2 patients were at TNM stage I, 9 IIA, one IIIB, 9 IV. 15 patients received systemic therapy (ST pNEN group) due to advanced disease or contraindications to surgery: 5 were at stage IIA, 2 IIB, 8 IV.

Results

The median follow-up for the entire cohort was 50 months. Survival was similar in the FU and SR pNEN groups, but significantly worst in the ST pNEN patients (log-rank test P <0.05). The 4-year survival rate was 100% in the FU pNEN group, 90.5% among the SR pNEN patients, 61% for the ST pNEN ones (p <0.0001). The disease remained stable in all but one patient in the FU pNEN group, whereas six patients in the SR group and five in the ST group showed disease progression.

Conclusions

The “wait-and-watch” approach to early-stage small pNENs appears to be safe although further studies are needed to confirm these results in larger cohorts of patients.

Surgical Management of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are a rare, heterogeneous group of neoplasms infamous for their endocrinopathies. Up to 90% of PNETs, however, are nonfunctional and are frequently detected incidentally on axial imaging during the evaluation of vague abdominal symptoms. Surgery remains the mainstay of therapy for patients diagnosed with both functional and nonfunctional PNETs. However, the multifaceted nature of PNETs challenges treatment decision making. In general, resection is recommended for patients with acceptable perioperative risk and amenable lesions.

Multidisciplinary management of nonfunctional neuroendocrine tumor of the pancreas

Pancreatic neuroendocrine tumors (PNETs) are a rare and diverse group of tumors; nonfunctional (NF) PNETs account for the majority of cases. Most patients with NF-PNETs have metastatic disease at the time of presentation. A variety of treatment modalities exist, including medical, liver directed, and surgical treatments. Aggressive surgical management is associated with prolonged survival, however available data are limited by selection bias and the frequent combination of PNETs with carcinoid tumors. Although few patients with metastatic disease will be cured, application of currently available therapies in a multidisciplinary setting can lead to excellent outcomes with prolonged patient survival.

Pancreatic neuroendocrine tumors: Challenges in an underestimated disease

Pancreatic neuroendocrine tumours (PanNETs) are considered a relatively unusual oncologic entity. Due to its relative good prognosis, surgery remains the goal standard therapy not only in localized disease but also in the setting of locally or metastatic disease. Most of the patients are diagnosed in metastatic scenario, where multidisciplinary approach based on surgery, chemotherapies, liver-directed and/or molecular targeted therapies are commonly used. Owing to a deeper molecular knowledge of this disease, these targeted therapies are nowadays widely implemented, being the likely discovery of predictive biomarkers that would allow its use in other settings. This review is focused on describing the different classifications, etiology, prognostic biomarkers and multidisciplinary approaches that are typically used in PanNET.