Achieving eugastrinemia in MEN1 patients: both duodenal inspection and formal lymph node dissection are important

Evaluation and Surgical Management of Multiple Endocrine Neoplasias

Multiple endocrine neoplasia (MEN) syndromes are rare autosomal dominant diseases that are associated with a mixture of both endocrine and non-endocrine tumors. Traditionally, there are 2 types of MEN that have unique clinical associations: MEN 1 (parathyroid hyperplasia, pancreatic neuroendocrine tumors, and pituitary tumors) and MEN 2 (medullary thyroid carcinoma and pheochromocytoma), which is further classified into MEN 2A (adds parathyroid adenomas) and 2B (adds ganglioneuromas and marfanoid habitus). Many of the endocrine tumors are resected surgically, and the pre, intra, and postoperative management strategies used must take into account the high recurrence rates asscioated with MEN tumors.

[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.

European Neuroendocrine Tumor Society 2023 guidance paper for functioning pancreatic neuroendocrine tumour syndromes

This ENETS guidance paper aims to provide practical advice to clinicians for the diagnosis, treatment and follow-up of functioning syndromes in pancreatic neuroendocrine tumours (NET). A NET-associated functioning syndrome is defined by the presence of a clinical syndrome combined with biochemical evidence of inappropriately elevated hormonal levels. Different hormonal syndromes can be encountered in pancreatic NET patients, including insulinoma, gastrinoma as well as the rare glucagonoma, VIPoma, ACTHoma, PTHrPoma, carcinoid syndrome, calcitoninoma, GHRHoma and somatostatinoma. The recommendations provided in this paper focus on the biochemical, genetic and imaging work-up as well as therapeutic management of the individual hormonal syndromes in well-differentiated, grade 1-3, functioning NET with the primary tumour originating in the pancreas, and for specific subtypes also in the duodenum.

Metastatic Patterns of Duodenopancreatic Neuroendocrine Tumors in Patients With Multiple Endocrine Neoplasia Type 1

Patients with multiple endocrine neoplasia 1 syndrome (MEN1) often develop multifocal duodenopancreatic neuroendocrine tumors (dpNETs). Nonfunctional pancreatic neuroendocrine tumors (PanNETs) and duodenal gastrinomas are the most frequent origins of metastasis. Current guidelines recommend surgery based on tumor functionality, size ≥2 cm, grade or presence of lymph node metastases. However, in case of multiple primary tumors it is often unknown which specific tumor metastasized. This study aims to unravel the relationship between primary dpNETs and metastases in patients with MEN1 by studying endocrine differentiation. First, it was shown that expression of the endocrine differentiation markers ARX and PDX1 was concordant in 18 unifocal sporadic neuroendocrine tumors (NETs) and matched metastases. Thereafter, ARX, PDX1, Ki67 and gastrin expression, and the presence of alternative lengthening of telomeres were determined in 137 microscopic and macroscopic dpNETs and 36 matched metastases in 10 patients with MEN1. ARX and PDX1 H-score clustering was performed to infer relatedness. For patients with multiple metastases, similar intrametastases transcription factor expression suggests that most metastases (29/32) originated from a single NET of origin, while few patients may have multiple metastatic primary NETs. In 6 patients with MEN1 and hypergastrinemia, periduodenopancreatic lymph node metastases expressed gastrin, and clustered with minute duodenal gastrinomas, not with larger PanNETs. PanNET metastases often clustered with high grade or alternative lengthening of telomeres-positive primary tumors. In conclusion, for patients with MEN1-related hypergastrinemia and PanNETs, a duodenal origin of periduodenopancreatic lymph node metastases should be considered, even when current conventional and functional imaging studies do not reveal duodenal tumors preoperatively.

Incidence of Lymph Node Metastases and Impact of Radical Surgery for Duodenal Neuroendocrine Tumors

BACKGROUND

Despite the high frequency of regional lymph node (LN) metastases associated with duodenal neuroendocrine tumors (D-NETs), the impact of these metastases on survival and the ideal extent of LN dissection are unknown. We used the National Cancer Database (NCDB) to investigate factors associated with survival, including LN metastases and types of surgery, in patients with D-NETs.

METHODS

All patients with D-NETs recorded in the NCDB between 2004 and 2016 were included in the study. We applied a multivariate Cox regression model to assess the relationship between the clinicopathological characteristics and overall survival (OS).

RESULTS

We identified 7613 patients, among whom 4886 local excisions and 233 radical surgeries had been performed. Among patients with at least 1 LN pathologically examined, the overall incidence of LN metastasis was 41.2%. For all patients, the median OS was 10.6 years. Univariate analyses showed equivalent OS in N0 and N1 groups (HR,0.83; 95% CI,0.64-1.09) and diminished OS in those who had undergone radical surgery compared with those who had undergone local resection (HR,1.35; 95% CI,1.02-1.8). In multivariable analyses, tumor size >50 mm and having more than 9 positive LNs were associated with diminished OS (HR,1.64 and 5.2; 95% CI,1.25-2.16 and 1.91-14.18), whereas the type of surgery did not remain in the model.

CONCLUSION

Our study revealed that the presence of regional LN metastases and extent of surgery did not affect OS among patients with D-NETs. Radical resection to clear occult LN metastases for nonfunctioning, sporadic D-NETs was not supported by the current study.

New therapies for patients with multiple endocrine neoplasia type 1

In 1953, for the first time, Paul Wermer described a family presenting endocrine gland neoplasms over several generations. The transmission was autosomal dominant and the penetrance was high. Forty years later in 1997, the multiple endocrine neoplasia type 1 (MEN1) gene was sequenced, thus enabling diagnosis and early optimal treatment. Patients carrying the MEN1 gene present endocrine but also non-endocrine tumors. Parathyroid, pancreatic and pituitary impairment are the three main types of endocrine involvement. The present article details therapeutic management of hyperparathyroidism, neuroendocrine pancreatic tumors and pituitary adenomas in patients carrying the MEN1 gene. Significant therapeutic progress has in fact been made in the last few years. As concerns the parathyroid glands, screening of family members and regular monitoring of affected subjects now raise the question of early management of parathyroid lesions and optimal timing of parathyroid surgery. As concerns the duodenum-pancreas, proton-pump inhibitors are able to control gastrin-secreting syndrome, reducing mortality in MEN1 patients. Mortality in MEN1 patients is no longer mainly secondary to uncontrolled hormonal secretion but to metastatic (mainly pancreatic) disease progression. Tumor risk requires regular monitoring of morphological assessment, leading to iterative pancreatic surgery in a large number of patients. Finally, pituitary adenomas in MEN1 patients are traditionally described as aggressive, invasive and resistant to medical treatment. However, regular pituitary screening showed them to be in fact infra-centimetric and non-secreting in the majority of patients. Consequently, it is necessary to regularly monitor MEN1 patients, with regular clinical, biological and morphological work-up. Several studies showed that this regular monitoring impairs quality of life. Building a relationship of trust between patients and care provider is therefore essential. It enables the patient to be referred for psychological or psychiatric care in difficult times, providing long-term support and preventing any breakdown in continuity of care.

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.

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

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

Pancreatic neuroendocrine tumors in MEN1 disease: a mono-centric longitudinal and prognostic study

PURPOSE

Multiple endocrine neoplasia type 1 (MEN1) is an inherited endocrine neoplastic syndrome associated with a greater risk of endocrine tumor development like pancreatic neuroendocrine tumors (p-NET), with different clinical characteristics from sporadic ones. This paper aims to compare clinical, hystological and morphological aspects of p-NET in patients affected from MEN1 (MEN1+) and not-affected ones (MEN1-).

METHODS

We performed a retrospective observational study. Data was collected between December 2010 and December 2015, including patients with a histological diagnosis of p-NET and radiological imaging. We compared clinical, histological, radiological, and prognostic aspects of MEN+ p-NET with MEN-1 p-NET.

RESULTS

Of the 45 patients enrolled, 13 MEN1+ and 21 MEN1- cases were analyzed. Frequency of not secreting p-NETs and insulin secreting p-NETs, histopathological grades and Ki67 expression were superimposable between MEN1+ and MEN1- patients. MEN1+ pNETs are more often multicentric compared to MEN1- pNETs. Frequency of liver and nodes metastatic spread was higher in MEN1- p-NET compared to MEN1+ p-NET. Analyzing p-NET according to the disease outcome, we found that recovered and stable p-NETs in MEN1+ patients, compared to MEN1- cases, are diagnosed at lower age (p = 0.04/p = 0.002) and that are more frequently multifocal lesions (p = 0.009/p = 0.002).

CONCLUSIONS

In our study pNETs in MEN1+ and pNETs in MEN1- don't significantly differ for prognosis but only for clinical features. p-NET stage disease and prognosis can be positively influenced by early diagnosis and screening in index patients' first-degree relatives.

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

Multiple endocrine neoplasia type 1 is a rare autosomal inherited disorder associated with a high risk for patients to simultaneously develop tumors of the parathyroid glands, duodenopancreatic neuroendocrine tumors and tumors of the anterior pituitary gland. Early identification of MEN1 in patients enables presymptomatic screening of manifestations, which makes timely interventions possible with the intention to prevent morbidity and mortality. Causes of death nowadays have shifted toward local or metastatic progression of malignant neuroendocrine tumors. In early cohorts, complications like peptic ulcers in gastrinoma, renal failure in hyperparathyroidism, hypoglycemia and acute hypercalcemia were the primary causes of early mortality. Improved medical treatments of these complications led to a significantly improved life expectancy. The MEN1 landscape is still evolving, considering the finding of breast cancer as a new MEN1-related manifestation and ongoing publications on follow-up and medical care for patients with MEN1. This review aims at summarizing the most recent insights into the follow-up and medical care for patients with MEN1 and identifying the gaps for future research.

Controversies in surgery for multiple endocrine neoplasia type 1-associated Zollinger–Ellison syndrome

Zollinger–Ellison syndrome (ZES) is a common manifestation of multiple endocrine neoplasia type 1 (MEN1). At least 90% of MEN1-ZES patients have multiple duodenal gastrinomas, making the duodenum the target organ of ZES. The indication and the timing of surgery in MEN1-ZES is controversial, since there is yet no parameter that indicates an aggressive course of disease and long-term survival is generally good. An imageable, most likely nonfunctioning pancreatic neuroendocrine neoplasm (pNEN) >1–2 cm seems to be a good surrogate parameter to indicate surgery in order to prevent distant metastatic pNEN disease, although some groups indicate surgery at the time of biochemical ZES evidence. The optimal surgical procedure is also controversial. Different strategies encomprise local excision via duodenotomy with or without distal pancreatic resection and regional lymphadenectomy to partial pancreaticoduodenectomy. At present, the timing and type of surgery for MEN1-ZES should be individualized according to patient’s characteristics and preference.

The genetics of endocrine neoplasia

The hereditary endocrine neoplasias are characterized by the development of benign or malignant tumors in more than one endocrine tissue. These tumors typically occur at a younger age than sporadic endocrine tumors and follow an autosomal dominant pattern of inheritance. Because of the age-related penetrance and extreme phenotypic variability both within and between families, clinicians cannot always rely on the family history to make the diagnosis. Recognition of the features of a hereditary endocrine syndrome can allow for appropriate and timely risk assessment, genetic counseling and genetic testing, and identification of at-risk family members who may benefit from early and regular screening.

Thoracic and duodenopancreatic neuroendocrine tumors in multiple endocrine neoplasia type 1: natural history and function of menin in tumorigenesis

Mutations of the multiple endocrine neoplasia type 1 (MEN1) gene lead to loss of function of its protein product menin. In keeping with its tumor suppressor function in endocrine tissues, the majority of the MEN1-related neuroendocrine tumors (NETs) show loss of heterozygosity (LOH) on chromosome 11q13. In sporadic NETs, MEN1 mutations and LOH are also reported, indicating common pathways in tumor development. Prevalence of thymic NETs (thNETs) and pulmonary carcinoids in MEN1 patients is 2-8%. Pulmonary carcinoids may be underreported and research on natural history is limited, but disease-related mortality is low. thNETs have a high mortality rate. Duodenopancreatic NETs (dpNETs) are multiple, almost universally found at pathology, and associated with precursor lesions. Gastrinomas are usually located in the duodenal submucosa while other dpNETs are predominantly pancreatic. dpNETs are an important determinant of MEN1-related survival, with an estimated 10-year survival of 75%. Survival differs between subtypes and apart from tumor size there are no known prognostic factors. Natural history of nonfunctioning pancreatic NETs needs to be redefined because of increased detection of small tumors. MEN1-related gastrinomas seem to behave similar to their sporadic counterparts, while insulinomas seem to be more aggressive. Investigations into the molecular functions of menin have led to new insights into MEN1-related tumorigenesis. Menin is involved in gene transcription, both as an activator and repressor. It is part of chromatin-modifying protein complexes, indicating involvement of epigenetic pathways in MEN1-related NET development. Future basic and translational research aimed at NETs in large unbiased cohorts will clarify the role of menin in NET tumorigenesis and might lead to new therapeutic options.

Biliary tree gastrinomas in multiple endocrine neoplasia type 1 syndrome

AIM: To describe our patients affected with ectopic biliary tree gastrinoma and review the literature on this topic.

METHODS: Between January 1992 and June 2012, 28 patients affected by duodenopancreatic endocrine tumors in multiple endocrine neoplasia type 1 (MEN1) syndrome underwent surgery at our institution. This retrospective review article analyzes our experience regarding seventeen of these patients subjected to duodenopancreatic surgery for Zollinger-Ellison syndrome (ZES). Surgical treatment consisted of duodenopancreatectomy (DP) or total pancreatectomy (TP). Regional lymphadenectomy was always performed. Any hepatic tumoral lesions found were removed during surgery. In MEN1 patients, removal of duodenal lesions can sometimes lead to persistence or recurrence of hypergastrinemia. One possible explanation for this unfavorable outcome could be unrecognized ectopic localization of gastrin-secreting tumors. This study described three cases among the seventeen patients who were found to have an ectopic gastrinoma located in the biliary tree.

RESULTS: Seventeen MEN1 patients affected with ZES were analyzed. The mean age was 40 years. Fifteen patients underwent DP and two TP. On histopathological examination, duodeno pancreatic endocrine tumors were found in all 17 patients. Eighty-one gastrinomas were detected in the first three portions of the duodenum. Only one gastrinoma was found in the pancreas. The mean number of gastrinomas per patient was 5 (range 1-16). Malignancy was established in 12 patients (70.5%) after lymph node, liver and omental metastases were found. Three patients exhibited biliary tree gastrinomas as well as duodenal gastrinoma(s). In two cases, the ectopic gastrinoma was removed at the same time as pancreatic surgery, while in the third case, the biliary tree gastrinoma was resected one year after DP because of recurrence of ZES.

CONCLUSION: These findings suggest the importance of checking for the presence of ectopic gastrinomas in the biliary tree in MEN1 patients undergoing ZES surgery.

Genetic and clinical features of multiple endocrine neoplasia types 1 and 2

Multiple endocrine neoplasia (MEN) are clinical inherited syndromes affecting different endocrine glands. Three different patterns of MEN syndromes can occur (MEN 1, MEN 2A, and MEN 2B). MEN syndromes are very rare, affect all ages and both sexes are equally affected. MEN 1 is characterized by the neoplastic transformation of the parathyroid glands, pancreatic islets, anterior pituitary, and gastrointestinal tract. Heterozygous MEN 1 germline mutations have been detected in about 70–80% of patients with MEN 1. The mutations are scattered throughout the entire genomic sequence of the gene. MEN 1 patients are characterized by variable clinical features, thus suggesting the lack of a genotype-phenotype correlation. Therapeutical approaches are different according to the different endocrinopathies. The prognosis is generally good if adequate treatment is provided. In MEN 2 syndromes, the medullary thyroid cancer (MTC) is almost invariably present and can be associated with pheochromocytoma (PHEO) and/or multiple adenomatosis of parathyroid glands with hyperparathyroidism (PHPT). The different combination of the endocrine neoplasia gives origin to 3 syndromes: MEN 2A, MEN 2B, and FMTC. The clinical course of MTC varies considerably in the three syndromes. It is very aggressive in MEN 2B, almost indolent in the majority of patients with FMTC and with variable degrees of aggressiveness in patients with MEN 2A. Activating germline point mutations of the RET protooncogene are present in 98% of MEN 2 families. A strong genotype-phenotype correlation has been observed and a specific RET mutation may be responsible for a more or less aggressive clinical course. The treatment of choice for primary MTC is total thyroidectomy with central neck lymph nodes dissection. Nevertheless, 30% of MTC patients, especially in MEN 2B and 2A, are not cured by surgery. Recently, developed molecular therapeutics that target the RET pathway have shown very promising activity in clinical trials of patients with advanced MTC. MEN 2 prognosis is strictly dependent on the MTC aggressiveness and thus on the success of the initial treatment.

Surgery for a gastroenteropancreatic neuroendocrine tumor (GEPNET) in multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominantly inherited endocrine tumor syndrome characterized by tumor development in various endocrine organs such as the parathyroid, endocrine pancreas, anterior pituitary and adrenal cortex. The first extensive database for Asian patients with MEN1 was established by the MEN Consortium of Japan. Although the clinical features of Japanese patients with MEN1 are similar to those from Western countries, there are several characteristic differences between them. In particular, gastroenteropancreatic neuroendocrine tumor (GEPNET) is seen in approximately 60 % of patients with MEN1 in Japan. Although its development is the strongest prognostic factor in patients with MEN1, the characteristics of MEN1-associated GEPNET still remain unclear. This is especially true for the differences in clinical features of GEPNET with and without MEN1. Improved long-term survival is obtained by curative surgery for patients with MEN1-associated GEPNET. The current surgical indications are expanding even in patients with hepatic metastases because of the improved surgical outcome. This article reviews the clinical characteristics in these patients with a particular focus on surgery, diagnosis, surgical indications, surgical method, and surgical outcome.

Gastroenteropancreatic neuroendocrine tumors in multiple endocrine neoplasia type 1

We reviewed the literature about entero-pancreatic neuroendocrine tumors in Multiple Endocrine Neoplasia type 1 syndrome (MEN1) to clarify their demographic features, localization imaging, practice, and appropriate therapeutical strategies, analyzing the current approach to entero-pancreatic neuroendocrine tumors in MEN1. Despite the fact that hyperparathyroidism is usually the first manifestation of MEN1, the penetrance of these tumors is similar. They are characterized by multiplicity of lesions, variable expression of the tumors, and propensity for malignant degeneration. Both the histological type and the size of MEN1 neuroendocrine tumors correlate with malignancy. Monitoring of pancreatic peptides and use of imaging exams allow early diagnosis and prompt surgical treatment, resulting in prevention of metastatic disease and improvement of long-term survival. Surgery is often the treatment of choice for MEN1-neuroendocrine tumors. The rationale for surgical approach is to curtail malignant progression of the disease, and to cure the associated biochemical syndrome, should it be present.