Natural History of MEN1 GEP-NET: Single-Center Experience After a Long Follow-Up

A New Medical Therapy for Multiple Endocrine Neoplasia Type 1?

Pancreatic neuroendocrine tumours (pNETs) are a major manifestation of multiple endocrine neoplasia type 1 (MEN1), and the most significant cause of morbidity and mortality in this disorder. There is some evidence that the early use of somatostatin analogues can retard progression, especially of small non-functioning tumours, but there are no other prophylactic therapies for patients, and the treatment of metastatic disease is similar to that for sporadic pNETs. A recent study has shown that in cell line and animal models, MEN1 mutations lead to an upregulation of the enzyme dihydroorotate dehydrogenase (DHODH), which is involved in increasing precursor metabolites for the synthesis of pyrimidines. In these studies, blockade of this pathway by various means, including the DHODH inhibitor leflunomide, attenuates cell growth and tumour progression, suggesting a critical dependence on DHODH specifically in MEN1-mutated tissue. Preliminary clinical studies in three patients with MEN1 and pNETs have indicated some therapeutic potential of this drug, which has previously been used for some years in patients with rheumatoid arthritis. It is suggested that further clinical trials of this re-purposed drug are indicated to evaluate its potential for the treatment of patients with MEN1 and pNETS. This article describes the clinical problem of MEN1 and pNETs, and reviews the recent publication reporting on these initial results.

Update on the clinical management of multiple endocrine neoplasia type 1

This review provides an overview of novel insights in the clinical management of patients with Multiple Endocrine Neoplasia Type 1, focusing on the last decade since the last update of the MEN1 guidelines. With regard to Diagnosis: Mutation-negative patients with 2/3 main manifestations have a different clinical course compared to mutation-positive patients. As for primary hyperparathyroidism: subtotal parathyroidectomy is the initial procedure of choice. Current debate centres around the timing of initial parathyroidectomy as well as the controversial topic of unilateral clearance in young patients. For duodenopancreatic neuroendocrine tumours (NETs), the main challenge is accurate and individualized risk stratification to enable personalized surveillance and treatment. Thymus NETs remain one of the most aggressive MEN1-related tumours. Lung NETs are more frequent than previously thought, generally indolent, but rare aggressive cases do occur. Pituitary adenomas are most often prolactinomas and nonfunctioning microadenomas with an excellent prognosis and good response to therapy. Breast cancer is recognized as part of the MEN1 syndrome in women and periodical screening is advised. Clinically relevant manifestations are already seen at the paediatric age and initiating screening in the second decade is advisable. MEN1 has a significant impact on quality of life and US data show a significant financial burden. In conclusion, patient outcomes have improved, but much is still to be achieved. For care tailored to the needs of the individual patient and improving outcomes on an individual basis, studies are now needed to define predictors of tumour behaviour and effects of more individualized interventions.

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.

Multiple endocrine neoplasia type 1 combined with thyroid neoplasm: A case report and review of literatures

BACKGROUND

Multiple endocrine neoplasia type 1 (MEN1) is a rare hereditary tumor syndrome inherited in an autosomal dominant manner and presents mostly as parathyroid, endocrine pancreas (such as gastrinoma) and anterior pituitary tumors. At present, papillary thyroid carcinoma (PTC) and nodular goiter are not regarded as components of MEN1.

CASE SUMMARY

A 35-year-old woman presented with MEN1 accompanied by coinstantaneous PTC and nodular goiter. The pathological diagnosis was PTC with cervical lymph node metastasis, nodular goiter, parathyroid cyst and adenomatoid hyperplasia. Genetic testing was performed and a MEN1 gene mutation was detected. The patient underwent unilateral lobectomy of the thyroid gland and surgical removal of the parathyroid tumors. At 18 mo of follow-up, ultrasonic examination of the neck showed no abnormality. Serum calcium and parathyroid hormone levels were normal. No new MEN1-associated tumors were detected.

CONCLUSION

The role of inactivating mutations of MEN1 gene in tumorigenesis of PTC and/or nodular goiter remains to be determined by more case reports and further research.

Diagnosing pancreatic neuroendocrine tumors in patients with multiple endocrine neoplasia type 1 in daily practice

BACKGROUND

In multiple endocrine neoplasia type 1 (MEN1), pancreatic neuroendocrine tumors (PanNETs) have a high prevalence and represent the main cause of death. This study aimed to assess the diagnostic accuracy of the currently used conventional pancreatic imaging techniques and the added value of fine needle aspirations (FNAs).

METHODS

Patients who had at least one imaging study were included from the population-based MEN1 database of the DutchMEN Study Group from 1990 to 2017. Magnetic resonance imaging (MRI), computed tomography (CT), endoscopic ultrasonography (EUS), FNA, and surgical resection specimens were obtained. The first MRI, CT, or EUS was considered as the index test. For a comparison of the diagnostic accuracy of MRI versus CT, patients with their index test taken between 2010 and 2017 were included. The reference standard consisted of surgical histopathology or radiological follow-up.

RESULTS

A total of 413 patients (92.8% of the database) underwent 3,477 imaging studies. The number of imaging studies per patient increased, and a preference for MRI was observed in the last decade. Overall diagnostic accuracy was good with a positive (PPV) and negative predictive value (NPV) of 88.9% (95% confidence interval, 76.0-95.6) and 92.8% (89.4-95.1), respectively, for PanNET in the pancreatic head and 92.0% (85.3-96.0) and 85.3% (80.5-89.1), respectively, in the body/tail. For MRI, PPV and NPV for pancreatic head tumors were 100% (76.1-100) and 87.1% (76.3-93.6) and for CT, 60.0% (22.9-88.4) and 70.4% (51.3-84.3), respectively. For body/tail tumors, PPV and NPV were 91.3% (72.0-98.8) and 87.0% (75.3-93.9), respectively, for MRI and 100% (74.9-100) and 77.8% (54.3-91.5), respectively, for CT. Pathology confirmed a PanNET in 106 out of 110 (96.4%) resection specimens. FNA was performed on 34 lesions in 33 patients and was considered PanNET in 24 [all confirmed PanNET by histology (10) or follow-up (14)], normal/cyst/unrepresentative in 6 (all confirmed PanNET by follow-up), and adenocarcinoma in 4 (2 confirmed and 2 PanNET). Three patients, all older than 60 years, had a final diagnosis of pancreatic adenocarcinoma.

CONCLUSION

As the accuracy for diagnosing MEN1-related PanNET of MRI was higher than that of CT, MRI should be the preferred (non-invasive) imaging modality for PanNET screening/surveillance. The high diagnostic accuracy of pancreatic imaging and the sporadic occurrence of pancreatic adenocarcinoma question the need for routine (EUS-guided) FNA.

Network Theory and Switching Behaviors: A User Guide for Analyzing Electronic Records Databases

As part of studies that employ health electronic records databases, this paper advocates the employment of graph theory for investigating drug-switching behaviors. Unlike the shared approach in this field (comparing groups that have switched with control groups), network theory can provide information about actual switching behavior patterns. After a brief and simple introduction to fundamental concepts of network theory, here we present (i) a Python script to obtain an adjacency matrix from a records database and (ii) an illustrative example of the application of network theory basic concepts to investigate drug-switching behaviors. Further potentialities of network theory (weighted matrices and the use of clustering algorithms), along with the generalization of these methods to other kinds of switching behaviors beyond drug switching, are discussed.

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.

Complications After Major Surgery for Duodenopancreatic Neuroendocrine Tumors in Patients with MEN1: Results from a Nationwide Cohort

Background

Little is known about complications after major duodenopancreatic surgery for duodenopancreatic neuroendocrine tumors (dpNETs) in multiple endocrine neoplasia type 1 (MEN1). Therefore, the incidence and severity of complications after major surgery for MEN1-related dpNETs were assessed.

Methods

Patients were selected from the population-based Dutch MEN1 database if they had undergone a Whipple procedure or total pancreatectomy from 2003 to 2017. Complications were graded according to the Clavien–Dindo classification (grade III or higher complications were considered a severe complication) and definitions from the International Study Group of Pancreatic Surgery. The Cumulative Complication Index (CCI^®) was calculated as the sum of all complications weighted for their severity. Univariable logistic regression was performed to assess potential associations between predictor candidates and a severe complication.

Results

Twenty-seven patients (median age 43 years) underwent a major duodenopancreatic resection, including 14 Whipple procedures and 13 total pancreatectomies. Morbidity and mortality were 100% (27/27) and 4% (1/27), respectively. A severe complication occurred in 17/27 (63%) patients. The median CCI^® was 47.8 [range 8.7–100]. Grade B/C pancreatic fistulas, delayed gastric emptying, bile leakage, hemorrhage, and chyle leakage occurred in 7/14 (50%), 10/27 (37%), 1/27 (4%), 7/27 (26%), 3/27 (11%) patients, respectively. Patients with a severe complication had longer operative time and higher blood loss. After Whipple, new-onset endocrine and exocrine insufficiency occurred in 1/13 and 9/14 patients, respectively.

Conclusions

Major duodenopancreatic surgery in MEN1 is associated with a very high risk of severe complications and cumulative burden of complications and should therefore be reserved for a select subgroup of patients with MEN1-related dpNETs.

Supplementary Information

The online version of this article (10.1245/s10434-020-09496-1) contains supplementary material, which is available to authorized users.

Prognosis after surgery for multiple endocrine neoplasia type 1-related pancreatic neuroendocrine tumors: Functionality matters

BACKGROUND

Metastasized pancreatic neuroendocrine tumors are the leading cause of death in patients with multiple endocrine neoplasia type 1. Aside from tumor size, prognostic factors of pancreatic neuroendocrine tumors are largely unknown. The present study aimed to assess whether the prognosis of patients with resected multiple endocrine neoplasia type 1-related nonfunctioning pancreatic neuroendocrine tumors differs from those with resected multiple endocrine neoplasia type 1-related insulinomas and assessed factors associated with prognosis.

METHODS

Patients who underwent resection of a multiple endocrine neoplasia type 1-related pancreatic neuroendocrine tumors between 1990 and 2016 were identified in 2 databases: the DutchMEN Study Group and the International MEN1 Insulinoma Study Group databases. Cox regression was performed to compare liver metastases-free survival of patients with a nonfunctioning pancreatic neuroendocrine tumors versus those with an insulinoma and to identify factors associated with liver metastases-free survival.

RESULTS

Out of 153 patients with multiple endocrine neoplasia type 1, 61 underwent resection for a nonfunctioning pancreatic neuroendocrine tumor and 92 for an insulinoma. Of the patients with resected lymph nodes, 56% (18/32) of nonfunctioning pancreatic neuroendocrine tumors had lymph node metastases compared to 10% (4/41) of insulinomas (P = .001). Estimated 10-year liver metastases-free survival was 63% (95% confidence interval 42%-76%) for nonfunctioning pancreatic neuroendocrine tumors and 87% (72%-91%) for insulinomas. After adjustment for size, World Health Organization tumor grade, and age, nonfunctioning pancreatic neuroendocrine tumors had an increased risk for liver metastases or death (hazard ratio 3.04 [1.47-6.30]). In pancreatic neuroendocrine tumors ≥2 cm, nonfunctioning pancreatic neuroendocrine tumors (2.99 [1.22-7.33]) and World Health Organization grade 2 (2.95 [1.02-8.50]) were associated with liver metastases-free survival.

CONCLUSION

Patients with resected multiple endocrine neoplasia type 1-related nonfunctioning pancreatic neuroendocrine tumors had a significantly lower liver metastases-free survival than patients with insulinomas. Postoperative counseling and follow-up regimens should be tumor type specific and at least consider size and World Health Organization grade.

Multiple Endocrine Neoplasia: Spectrum of Abdominal Manifestations

OBJECTIVE. Multiple endocrine neoplasia (MEN) syndromes are autosomal-dominant genetic disorders that predispose two or more organs of the endocrine system to tumor development. Although the diagnosis relies on clinical and serologic findings, imaging provides critical information for surgical management with the ultimate goal of complete tumor resection. CONCLUSION. This article reviews abdominal neoplasms associated with the various subtypes of MEN syndromes, with a focus on clinical presentation and characteristic imaging features.

One-Year Postoperative Mortality in MEN1 Patients Operated on Gastric and Duodenopancreatic Neuroendocrine Tumors: An AFCE and GTE Cohort Study

IMPORTANCE

In MEN1 patients with gastric and duodenopancreatic neuroendocrine tumors (GPD-NET), surgery aims to control secretions or to prevent metastatic spread, but after GPD-NET resection, postoperative mortality may be related to the surgery itself or to other associated MEN1 lesions with their own uncontrolled secretions or metastatic behavior.

OBJECTIVE

To analyze the causes of death within 1 year following a GPD-NET resection in MEN1 patients.

DESIGN

An observational study collecting data from the Groupe d'étude des Tumeurs Endocrines (GTE) database. The analysis considered the time between surgery and death (early deaths [<1 month after surgery] versus delayed deaths [beyond 1 month after surgery]) and the period (before 1990 vs after 1990). Causes of death were classified as related to GDP surgery, related to surgery for other MEN1 lesions or not related to MEN1 causes.

SETTING

GTE database which includes 1220 MEN1 patients and 441 GPD-NET resections.

PARTICIPANTS

Four hundred and forty-one GPD-NET resections.

MAIN OUTCOME MEASURES

The primary end point was postoperative mortality within 1 year after surgery.

RESULTS

Twenty-four patients met the inclusion criteria (2%). Median age at death was 50.5 years. Sixteen deaths occurred in the 30-day postoperative period (76%). Among the 8 delayed deaths, 3 occurred as a result of medical complications between 30 and 90 postoperative days. After 1990, mean age at death increased from 48 to 58 years (p = 0.09), deaths related to uncontrolled acid secretion disappeared (p < 0.001) and deaths related to associated MEN1 lesions increased from 8 to 54% (p = 0.16).

CONCLUSION

Surgery and uncontrolled secretions remain the two main causes of death in MEN1 patients operated for a GPD-NET tumor. Improving the prognosis of these patients requires a strict evaluation of the secretory syndrome and MEN1 aggressiveness before GDP surgery.

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.

Clinicopathological features and menin expression of pancreatic neuroendocrine neoplasm associated with multiple endocrine neoplasia type 1

Background/Purpose

We examined therapeutic strategies for pancreatic neuroendocrine neoplasm (pNEN) associated with MEN1 (M‐pNEN) by investigating clinicopathological features and menin expression.

Methods

Seventy‐seven patients who underwent resection of pNEN at our department from January 2001 to December 2017 were retrospectively analyzed. Immunohistochemical analysis of menin was performed using resected specimens.

Results

Seven patients (9%) met the diagnostic criteria for MEN1. M‐pNEN had more tumors (P < .01), a higher recurrence rate (P = .028), and higher residual pancreatic recurrence (P < .01) than sporadic pNEN (S‐pNEN). There were no significant differences in tumor size, lymph node metastasis, or World Health Organization grade between the two groups. Reduced menin staining in the tumor nuclei was found in 86% of M‐pNEN; whereas only 34% of S‐pNEN showed decreased nuclear staining. The remainder (66%) showed strong nuclear staining similar to normal islet cells (P = .0071). Furthermore, four patients (57%) with MEN1 had many microadenomas with reduced nuclear menin staining. Overall survival of M‐pNEN patients was significantly better than S‐pNEN patients (P = .049).

Conclusion

M‐pNEN patients tend to develop spatially and temporally multifocal pNENs. However, M‐pNEN patient prognosis is good with repeated surgeries at recurrence. Therefore, minimal resection with strict follow‐up is recommended rather than extensive pancreatic resections for consideration of recurrence in M‐pNEN.

Bone Metabolism and Vitamin D Implication in Gastroenteropancreatic Neuroendocrine Tumors

Patients affected by gastroenteropancreatic–neuroendocrine tumors (GEP–NETs) have an increased risk of developing osteopenia and osteoporosis, as several factors impact on bone metabolism in these patients. In fact, besides the direct effect of bone metastasis, bone health can be affected by hormone hypersecretion (including serotonin, cortisol, and parathyroid hormone-related protein), specific microRNAs, nutritional status (which in turn could be affected by medical and surgical treatments), and vitamin D deficiency. In patients with multiple endocrine neoplasia type 1 (MEN1), a hereditary syndrome associated with NET occurrence, bone damage may carry other consequences. Osteoporosis may negatively impact on the quality of life of these patients and can increment the cost of medical care since these patients usually live with their disease for a long time. However, recommendations suggesting screening to assess bone health in GEP–NET patients are missing. The aim of this review is to critically analyze evidence on the mechanisms that could have a potential impact on bone health in patients affected by GEP–NET, focusing on vitamin D and its role in GEP–NET, as well as on factors associated with MEN1 that could have an impact on bone homeostasis.

Lanreotide Therapy vs Active Surveillance in MEN1-Related Pancreatic Neuroendocrine Tumors < 2 Centimeters

PURPOSE

Pancreatic neuroendocrine tumors (pNETs) are frequent in multiple endocrine neoplasia type 1 (MEN1) syndrome. They are usually not surgically treated unless larger than 1 to 2 cm or a growth rate > 0.5 cm per year. Somatostatin analogues represent one of the main therapeutic options in pNETs, but they have never been prospectively investigated in MEN1-related pNETs. The aim of this study was to prospectively evaluate the effectiveness of lanreotide in patients with MEN1-related pNETs < 2 cm.

METHODS

MEN1 patients with 1 or more pNETs < 2 cm of maximal diameter were considered. Study design was prospective observational, comparing patients treated with lanreotide autogel 120 mg every 28 days (LAN group) and patients in active surveillance, not receiving any therapy (AS group).

RESULTS

Forty-two patients were enrolled: 23 in LAN and 19 in AS group. Median follow-up was 73 months. Initial imaging identified a total of 91 pNETs. The median progression-free survival was significantly longer in the LAN than in the AS group (median not reached vs 40 months, P < 0.001). In the LAN group, 4 patients had an objective tumor response, 15 patients had stable disease, while 4 had tumor progression. In the AS group, 13 patients had pNET progression, while 6 were stable.

CONCLUSIONS

This is the first prospective study evaluating the efficacy of somatostatin analogues in MEN1-related pNETs. These findings highlight that lanreotide autogel is effective as antiproliferative therapy in MEN1-related pNETs < 2cm, suggesting the utility of somatostatin analogues to arrest the development of tumor lesions as well as to delay or avoid pancreatic surgery.

True MEN1 or phenocopy? Evidence for geno-phenotypic correlations in MEN1 syndrome

PURPOSE

Multiple endocrine neoplasia type 1 is a rare tumor syndrome caused by germline mutations of MEN1 gene. Phenotype varies widely, and no definitive correlation with the genotype has been observed. Mutation-negative patients with MEN1-associated tumors represent phenocopies. By comparing mutation-positive and mutation-negative patients, we aimed to identify phenotype features predictive for a positive genetic test and to evaluate the role of MEN1 mutations in phenotype modulation.

METHODS

Mutation screeening of MEN1 gene by Sanger sequencing and assessment of clinical data of 189 consecutively enrolled probands and relatives were performed at our national and European Reference Center. Multiple ligation probe amplification analysis of MEN1 gene and Sanger sequencing of CDKN1B were carried out in clinically suspicious but MEN1-negative cases.

RESULTS

Twenty-seven probands and twenty family members carried MEN1 mutations. Five mutations have not been described earlier. Pronouncedly high number of phenocopies (>70%) was observed. Clinical suspicion of MEN1 syndrome emerged at significantly earlier age in MEN1-positive compared to MEN1-negative probands. Gastroenteropancreatic neuroendocrine tumors developed significantly earlier and more frequently in carriers compared to non-carriers. Probands with high-impact (frameshift, nonsense, large deletions) mutations, predicted to affect menin function significantly, developed GEP-NETs more frequently compared to low-impact (inframe and missense) mutation carriers.

CONCLUSIONS

MEN1 phenocopy is common and represents a significant confounder for the genetic testing. GEP-NET under 30 years best predicted a MEN1 mutation. The present study thus confirmed a previous proposal and suggested that GEP-NET under 30 years should be considered as a part of the indication criteria for MEN1 mutational analysis.