[Insulinomas in multiple endocrine neoplasia type 1. Report of a series of 44 cases by the multiple endocrine neoplasia study group]

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 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.

The impact of failure to achieve symptom control after resection of functional neuroendocrine tumors: An 8-institution study from the US Neuroendocrine Tumor Study Group

BACKGROUND

The goals of resection of functional neuroendocrine tumors (NETs) are two-fold: Oncological benefit and symptom control. The interaction between the two is not well understood.

METHODS

All patients with functional NETs of the pancreas, duodenum, and ampulla who underwent curative-intent resection between 2000 and 2016 were identified. Using Cox regression analysis, factors associated with reduced recurrence-free survival (RFS) were identified.

RESULTS

Two-hundred and thirty patients underwent curative-intent resection. Fifty-three percent were insulinomas, 35% gastrinomas, and 12% were other types. Twenty-one percent had a known genetic syndrome, 23% had lymph node (LN) positivity, 80% underwent an R0 resection, and 14% had no postoperative symptom improvement (SI). Factors associated with reduced RFS included noninsulinoma histology, the presence of a known genetic syndrome, LN positivity, R1 margin, and lack of SI. On multivariable analysis, only the failure to achieve SI following resection was associated with reduced RFS. Considering only those patients with an R0 resection, failure to achieve SI was associated with worse 3-year RFS compared with patients having SI (36% vs 80%; P = 0.006).

CONCLUSIONS

Failure to achieve symptomatic improvement after resection of functional NETs is associated with worse RFS. These patients may benefit from short-interval surveillance imaging postoperatively to assess for earlier radiographical disease recurrence.

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

BACKGROUND

The multiple endocrine neoplasia type 1 syndrome (MEN1) natural history is poorly evaluated, and few single-institution experiences about hereditary gastroenteropancreatic neuroendocrine tumors (GEP-NET) are reported. Our purpose is to analyze the role of GEP-NET in MEN1-related death, as well as the behavior of these lesions during follow-up.

METHODS

The study population consists of 77 patients diagnosed with MEN1 GEP-NET, regularly followed up since 1990. Extensive clinical data were prospectively recorded. Statistical analysis was performed both on the whole population of 77 patients and on two subgroups including patients who, during the long lasting study period, underwent GEP-NET surgery (50 pts) and who did not (27 pts), respectively.

RESULTS

Twenty-five males (32.5%) and 52 females (67.5%) were enrolled. Sixty-four patients had MEN1 family history (83.1%), and genetic mutation was detected in 67 cases (87%). The mean age at GEP-NET diagnosis was 41.4 years (SD = 13.6); 16 patients (20.8%) had GEP-NET diagnosed before age 30 and 12 cases (15.6%) before 1996. The mean interval time between MEN1 diagnosis and GEP-NET detection was 5.7 years (range -11/37; SD = 8.1 years). Overall, the mean follow-up time from MEN1 diagnosis was 15.8 years (SD = 9.7 years) and from GEP-NET diagnosis was 9.6 years (SD = 6.9 years). Gastrinoma was the most frequent functioning GEP-NET and pancreatoduodenectomy the most adopted surgery. GEP-NET progression affected 12 patients within the non-surgical group, while 18 subjects developed progression after surgery.

CONCLUSIONS

Our single-center data provide information on epidemiologic, clinical and pathological features of GEP-NET in MEN1 making possible to clarify their natural history.

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.

The treatment of hyperinsulinemic hypoglycaemia in adults: an update

BACKGROUND

Treatment of hyperinsulinemic hypoglycaemia (HH) is challenging due to the rarity of this condition and the difficulty of differential diagnosis. The aim of this article is to give an overview of the recent literature on the management of adult HH.

METHODS

A search for reviews, original articles, original case reports between 1995 and 2016 in PubMed using the following keywords: hyperinsulinemic hypoglycaemia, insulinoma, nesidioblastosis, gastric bypass, autoimmune hypoglycaemia, hyperinsulinism, treatment was performed.

RESULTS

One hundred and forty articles were selected and analysed focusing on the most recent treatments of HH.

CONCLUSIONS

New approaches to treatment of HH are available including mini-invasive surgical techniques and alternative local-regional ablative therapy for benign insulinoma and everolimus for malignant insulinoma. A correct differential diagnosis is of paramount importance to avoid unnecessary surgical operations and to implement the appropriate treatment mainly in the uncommon forms of HH, such as nesidioblastosis and autoimmune hypoglycaemia.

Operation for insulinomas in multiple endocrine neoplasia type 1: When pancreatoduodenectomy is appropriate

BACKGROUND

Distal pancreatectomy is the most frequent operation for insulinomas complicating multiple endocrine neoplasia type 1 insulinoma, although there are conditions for which a different operative approach might be preferable. In this article, we report the operative experience of a referral center for multiple endocrine neoplasia type 1 insulinoma.

METHODS

Twelve patients underwent operations between 1992 and 2015: 8 underwent a distal pancreatic resection, and 4 underwent a pancreatoduodenectomy. Enucleation of other macroadenomas present in the remnant pancreas was performed in 9 out of these 12 patients.

RESULTS

Operative complications (2 pancreatic fistulas and 2 cases of pancreatitis) occurred in 4 of the 8 distal pancreatic resections. In 1 patient, reoperation was required to resolve the complications of the first operation. At pathologic analysis, multiple insulinomas were found in 5 patients, lymph-nodal metastasis positive for insulin in 2 patients, multiple nonfunctioning pancreatic tumors in all patients, glucagonoma in 4 patients, and gastrinoma in the duodenum or lymph nodes in 4 patients. All the patients were treated successfully for the hypoglycemic/hyperinsulinemic syndrome with no clinical recurrence at a mean follow-up of 85 months (range 4-242 months). Recurrent nonfunctioning pancreatic tumor macroadenomas in the remnant pancreas occurred in only 1 of the 12 patients, and no progression of the gastrinomas was observed. None of the patients developed diabetes mellitus.

CONCLUSION

Resection of the most severely affected part of the pancreas, whether left or right, associated with enucleation of concomitant macroadenomas in the preserved pancreas is recommended for the treatment of hypoglycemic/hyperinsulinemic syndrome and to prevent malignant progression of nonfunctioning pancreatic tumors in patients with multiple endocrine neoplasia type 1. If the head of the pancreas is the most affected site and the Zollinger-Ellison syndrome is concomitant, then pancreatoduodenectomy should be preferred over distal pancreatectomy.

Multiple Endocrine Neoplasia: Genetics and Clinical Management

Early diagnosis of multiple endocrine neoplasia (MEN) syndromes is critical for optimal clinical outcomes; before the MEN syndromes can be diagnosed, they must be suspected. Genetic testing for germline alterations in both the MEN type 1 (MEN1) gene and RET proto-oncogene is crucial to identifying those at risk in affected kindreds and directing timely surveillance and surgical therapy to those at greatest risk of potentially life-threatening neoplasia. Pancreatic, thymic, and bronchial neuroendocrine tumors are the leading cause of death in patients with MEN1 and should be aggressively considered by at least biannual computed tomography imaging.

Long-term results of the surgical management of insulinoma patients with MEN1: a Groupe d'étude des Tumeurs Endocrines (GTE) retrospective study

OBJECTIVE

Management of insulinomas in the context of MEN1 remains poorly studied. The aim of this study was to evaluate long-term results of various surgical approaches in a large cohort of insulinoma-MEN1 patients.

DESIGN AND METHODS

Consecutive insulinoma-MEN1 patients operated on for a nonmetastatic insulinoma between 1957 and 2010 were retrospectively selected from the MEN1 database of the French Endocrine Tumor Group. The type of surgery was categorized as distal pancreatectomy (DP), total pancreatectomy/cephalic duodenopancreatectomy (TP/CDP), or enucleation (E). Primary endpoint was time until recurrence of hypoglycemia after initial surgery. Secondary endpoints were post-operative complications.

RESULTS

The study included 73 patients (median age=28 years). Surgical procedures were DP (n=46), TP/CDP (n=9), or E (n=18). After a median post-operative follow-up of 9.0 years (inter-quartile range (IQR): 2.5-16.5 years), 60/73 patients (82.2%) remained hypoglycemia free. E and TP/CDP were associated with a higher risk of recurrent hypoglycemia episodes (unadjusted hazard ratio: 6.18 ((95% CI: 1.54-24.8); P=0.010) for E vs DP and 9.51 ((95% CI: 1.85-48.8); P=0.007) for TP/CDP vs DP. After adjustment for International Union against Cancer pTNM classification, enucleation remained significantly associated with a higher probability of recurrence. Long-term complications had occurred in 20 (43.5%) patients with DP, five (55.6%) with TP/CDP, but in none of the patients who have undergone E (P=0.002).

CONCLUSION

In the French Endocrine database, DP is associated with a lower risk for recurrent hypoglycemia episodes. Due to lower morbidity, E alone might be considered as an alternative.

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.

Causes of death and prognostic factors in multiple endocrine neoplasia type 1: a prospective study: comparison of 106 MEN1/Zollinger-Ellison syndrome patients with 1613 literature MEN1 patients with or without pancreatic endocrine tumors

Multiple endocrine neoplasia type 1 (MEN1) is classically characterized by the development of functional or nonfunctional hyperplasia or tumors in endocrine tissues (parathyroid, pancreas, pituitary, adrenal). Because effective treatments have been developed for the hormone excess state, which was a major cause of death in these patients in the past, coupled with the recognition that nonendocrine tumors increasingly develop late in the disease course, the natural history of the disease has changed. An understanding of the current causes of death is important to tailor treatment for these patients and to help identify prognostic factors; however, it is generally lacking.To add to our understanding, we conducted a detailed analysis of the causes of death and prognostic factors from a prospective long-term National Institutes of Health (NIH) study of 106 MEN1 patients with pancreatic endocrine tumors with Zollinger-Ellison syndrome (MEN1/ZES patients) and compared our results to those from the pooled literature data of 227 patients with MEN1 with pancreatic endocrine tumors (MEN1/PET patients) reported in case reports or small series, and to 1386 patients reported in large MEN1 literature series. In the NIH series over a mean follow-up of 24.5 years, 24 (23%) patients died (14 MEN1-related and 10 non-MEN1-related deaths). Comparing the causes of death with the results from the 227 patients in the pooled literature series, we found that no patients died of acute complications due to acid hypersecretion, and 8%-14% died of other hormone excess causes, which is similar to the results in 10 large MEN1 literature series published since 1995. In the 2 series (the NIH and pooled literature series), two-thirds of patients died from an MEN1-related cause and one-third from a non-MEN1-related cause, which agrees with the mean values reported in 10 large MEN1 series in the literature, although in the literature the causes of death varied widely. In the NIH and pooled literature series, the main causes of MEN1-related deaths were due to the malignant nature of the PETs, followed by the malignant nature of thymic carcinoid tumors. These results differ from the results of a number of the literature series, especially those reported before the 1990s. The causes of non-MEN1-related death for the 2 series, in decreasing frequency, were cardiovascular disease, other nonendocrine tumors > lung diseases, cerebrovascular diseases. The most frequent non-MEN1-related tumor deaths were colorectal, renal > lung > breast, oropharyngeal. Although both overall and disease-related survival are better than in the past (30-yr survival of NIH series: 82% overall, 88% disease-related), the mean age at death was 55 years, which is younger than expected for the general population.Detailed analysis of causes of death correlated with clinical, laboratory, and tumor characteristics of patients in the 2 series allowed identification of a number of prognostic factors. Poor prognostic factors included higher fasting gastrin levels, presence of other functional hormonal syndromes, need for >3 parathyroidectomies, presence of liver metastases or distant metastases, aggressive PET growth, large PETs, or the development of new lesions.The results of this study have helped define the causes of death of MEN1 patients at present, and have enabled us to identify a number of prognostic factors that should be helpful in tailoring treatment for these patients for both short- and long-term management, as well as in directing research efforts to better define the natural history of the disease and the most important factors determining long-term survival at present.

Enucleation and limited pancreatic resection provide long-term cure for insulinoma in multiple endocrine neoplasia type 1

AIM

To assess the characteristics and long-term outcome after surgery in patients with multiple endocrine neoplasia type 1 (MEN1)-associated insulinoma.

METHODS

Retrospective analysis of prospectively collected data of MEN1 patients with organic hyperinsulinism at a tertiary referral center.

RESULTS

Thirteen (17%) of 74 patients with MEN1 had organic hyperinsulinism. The median age at diagnosis was 27 (range 9-48) years. In 7 patients insulinoma was the first manifestation of the syndrome. All patients had at least one pancreatic neuroendocrine neoplasm (pNEN) upon imaging, including CT, MRI or endoscopic ultrasonography. Seven patients had solitary lesions upon imaging, 4 patients had one dominant tumor with coexisting multiple small pNENs, and 2 patients had multiple lesions without dominance. Eight patients had limited resections (1 segmental resection, 7 enucleations), 4 subtotal distal pancreatectomies, and 1 patient a partial duodenopancreatectomy. There was no postoperative mortality. Six patients experienced complications, including pancreatic fistula in 5 patients. Pathological examination revealed median three (range 1-14) macro-pNENs sized between 6 and 40 mm, and a total of 14 potentially benign insulinomas were detected in the 13 patients. After median follow-up of 156 months, only 1 patient developed recurrent hyperinsulinism after initial enucleation. Twelve patients developed new pNENs in the pancreatic remnant and 4 patients underwent reoperations (3 for metastatic ZES, 1 for recurrent hyperinsulinism). One of 5 patients with an initial extended pancreatic resection developed insulin-dependent diabetes mellitus.

CONCLUSION

Enucleation and limited resection provide long-term cure for MEN1 insulinoma in patients with solitary or dominant tumors. Subtotal distal pancreatectomy should thus be preserved for patients with multiple pNENs without dominance given the risk of exocrine and endocrine pancreas insufficiency in the mostly young patients.

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.

Pancreatic endocrine tumors in multiple endocrine neoplasia type 1 syndrome: review of literature

OBJECTIVE

To analyze the surgical approach to multiple endocrine neoplasia type 1 (MEN 1)-related pancreatic endocrine tumors (PETs).

METHODS

We reviewed selected publications and our personal experience with MEN 1-associated PETs to delineate their general characteristics, current practice and controversies, preoperative imaging and intraoperative assessment, and appropriate therapeutic strategies including radical surgical procedures.

RESULTS

The penetrance of PETs in the setting of MEN 1 is similar to that of parathyroid tumors, even though hyperparathyroidism is usually the first manifestation of MEN 1 syndrome. In contrast with the sporadic counterparts, MEN 1-related PETs are characterized by an early onset, multiplicity of lesions, variable expression of the tumors, and propensity for malignant degeneration. Both the histologic type and the size of these tumors correlate with malignant potential.

CONCLUSION

The rationale for surgical considerations for these tumors is to curtail the malignant progression of the disease and to cure or aid in management of the associated biochemical syndromes. A surgical procedure is often the treatment of choice for PETs in patients with MEN 1. Monitoring of pancreatic peptides and use of diagnostic imaging allow an early pancreatic resection, in conjunction with prevention of metastatic PETs and improvement of long-term survival. Hepatic metastatic lesions can be successfully treated by surgical resection.

Presentation and outcome of pancreaticoduodenal endocrine tumors in multiple endocrine neoplasia type 1 syndrome

AIM

To assess presentation and outcome of pancreaticoduodenal endocrine tumors (PDETs) in a single center series of multiple endocrine neoplasia type 1 (MEN1) patients.

METHODS

Retrospective analysis of prospectively collected data of MEN1 patients observed at the University of Verona.

RESULTS

Thirty-one MEN1 patients had PDETs, including 16 nonfunctioning (NF), 6 insulinomas and 9 Zollinger-Ellison syndrome (ZES). In 16 of these patients (52%), PDET was the manifestation which led to the diagnosis of MEN1; among this group, 15 patients (94%) previously had unidentified primary hyperparathyroidism (PHPT), which was asymptomatic in 9 cases (60%). Of the 31 patients, 19 (61%) underwent curativesurgery and 13 (68%, 7 NF-PDETs, 4 insulinomas and 2 ZES) were disease-free after a median follow-up of 3 years (range: 0.5-15). One patient had debulking surgery with stable disease after 2 years of follow-up. Eight patients with NF-PDETs ≤20 mm and 2 with ZES, treated with a conservative approach, showed stable disease. One patient with insulinoma was lost to follow-up.

CONCLUSIONS

PDET may be the manifestation that leads to MEN1 diagnosis since the almost constant presence of PHPT is very often unrecognized or considered sporadic. Conversely, the presence of PDETs should be looked for in all patients presenting PHPT, even if asymptomatic, particularly before age 50. Surgery may be curative in the majority of insulinomas and can prolong disease-free survival in NF-PDET, but is not proven to be effective in ZES. A conservative approach can be safely reserved for patients with NF-PDETs ≤20 mm.

Multiple endocrine neoplasia type 1 simultaneous with various types of enteropancreatic endocrine tumors: one case report: lessons learned

Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal dominant disorder characterized by the development of parathyroid hyperplasia, pancreatic endocrine tumors, pituitary adenomas, and adrenal adenomas. We reported 1 case of MEN 1 simultaneous with gastrinoma and insulinoma; meanwhile, insulinomas were ectopic and recurrent. The genetic screening showed the mutation of 427del AT of the MEN 1 gene. Surgical removal is considered the treatment of choice, with limited adverse effects and relatively low morbidity and mortality. She was treated by means of several surgical strategies, resulting in improvement of the frequency and severity of the hypoglycemic episodes and a better quality of life.

Risk factors and causes of death in MEN1 disease. A GTE (Groupe d'Etude des Tumeurs Endocrines) cohort study among 758 patients

BACKGROUND

The natural history of multiple endocrine neoplasia type 1 (MEN1) is known through single-institution or single-family studies. We aimed to analyze the risk factors and causes of death in a large cohort of MEN1 patients.

METHODS

Overall, 758 symptomatic MEN1 patients were identified through the GTE network (Groupe d'étude des Tumeurs Endocrines), which involves French and Belgian genetics laboratories responsible for MEN1 diagnosis and 80 clinical reference centers. The causes of death were analyzed. A frailty model, including time-dependent variables, was used to assess the impact of each clinical lesion, except for hyperparathyroidism, on survival.

RESULTS

The median follow-up was 6.3 years. Female gender, family history of MEN1, and recent diagnosis were associated with a lower risk of death. Compared with nonaffected patients, those with thymic tumors (hazard ratio [HR] = 4.64, 95% CI = 1.73-12.41), glucagonomas-vipomas-somatostatinomas (HR = 4.29, 95% CI = 1.54-11.93), nonfunctioning pancreatic tumors (HR = 3.43, 95% CI = 1.71-6.88), and gastrinoma (HR = 1.89, 95% CI = 1.09-3.25) had a higher risk of death after adjustment for age, gender, and diagnosis period. The increased risk of death among patients with adrenal tumors was not significant, but three patients died from aggressive adrenal tumors. Pituitary tumors, insulinomas, and bronchial tumors did not increase the risk of death. The proportion of MEN1-related deaths decreased from 76.8 to 71.4% after 1990.

CONCLUSIONS

The prognosis of MEN1 disease has improved since 1980. Thymic tumors and duodenopancreatic tumors, including nonsecreting pancreatic tumors, increased the risk of death. Rare but aggressive adrenal tumors may also cause death. Most deaths were related to MEN1. New recommendations on abdominal and thoracic imaging are required.

[Hypoglycemia and insulinoma]

Insulinomas are rare causes of hypoglycemia. After having ruled out non insulinomatous causes of hypoglycemia in a patient in whom Whipple's triad is documented, hyperinsulinism must be demonstrated biochemically, either during a spontaneous hypoglycemic episode or, more often, during a supervised fast which may be prolonged up to 72 h. A mixed-meal test may also help to diagnose the very rare cases of postprandial hypoglycemia related to non insulinoma pancreatogenic hypoglycemic syndrome (NIPHS) or to some rare insulinomas. Only when diagnosis of hypoglycemic hyperinsulinism is made, the tumor localization process may be initiated. This may be difficult due to the small size of insulinomas (generally < 1 cm). Multimodal approach is necessary. The association of endoscopic ultrasound and CT-scan or MRI seems optimal. Octreoscan will be also performed. First results with a very new technique, the GLP-1 receptor imaging, are promising for localizing very small tumors. This localization aims to allow a sparing surgery; enucleation of benign tumors, if possible, allows a pancreatic tissue preservation in patients with quite normal survival.

Inherited pancreatic endocrine tumor syndromes: advances in molecular pathogenesis, diagnosis, management, and controversies

Pancreatic endocrine tumors (PETs) can occur as part of 4 inherited disorders, including Multiple Endocrine Neoplasia type 1 (MEN1), von Hippel-Lindau disease (VHL), neurofibromatosis 1 (NF-1) (von Recklinghausen disease), and the tuberous sclerosis complex (TSC). The relative frequency with which patients who have these disorders develop PETs is MEN1>VHL>NF-1>TSC. Over the last few years, there have been major advances in the understanding of the genetics and molecular pathogenesis of these disorders as well in the localization and the medical and surgical treatment of PETs in such patients. The study of PETs in these disorders not only has provided insights into the possible pathogenesis of sporadic PETs but also has presented several unique management and treatment issues, some of which are applicable to patients with sporadic PETs. Therefore, the study of PETs in these uncommon disorders has provided valuable insights that, in many cases, are applicable to the general group of patients with sporadic PETs. In this article, these areas are reviewed briefly along with the current state of knowledge of the PETs in these disorders, and the controversies that exist in their management are summarized briefly and discussed.

Gastrointestinal neuroendocrine tumors: pancreatic endocrine tumors

Pancreatic endocrine tumors (PETs) have long fascinated clinicians and investigators despite their relative rarity. Their clinical presentation varies depending on whether the tumor is functional or not, and also according to the specific hormonal syndrome produced. Tumors may be sporadic or inherited, but little is known about their molecular pathology, especially the sporadic forms. Chromogranin A appears to be the most useful serum marker for diagnosis, staging, and monitoring. Initially, therapy should be directed at the hormonal syndrome because this has the major initial impact on the patient's health. Most PETs are relatively indolent but ultimately malignant, except for insulinomas, which predominantly are benign. Surgery is the only modality that offers the possibility of cure, although it generally is noncurative in patients with Zollinger-Ellison syndrome or nonfunctional PETs with multiple endocrine neoplasia-type 1. Preoperative staging of disease extent is necessary to determine the likelihood of complete resection although debulking surgery often is believed to be useful in patients with unresectable tumors. Once metastatic, biotherapy is usually the first modality used because it generally is well tolerated. Systemic or regional therapies generally are reserved until symptoms occur or tumor growth is rapid. Recently, a number of newer agents, as well as receptor-directed radiotherapy, are being evaluated for patients with advanced disease. This review addresses a number of recent advances regarding the molecular pathology, diagnosis, localization, and management of PETs including discussion of peptide-receptor radionuclide therapy and other novel antitumor approaches. We conclude with a discussion of future directions and unsettled problems in the field.

Observatoire francophone des néoplasies endocriniennes multiples de type 1. Un outil du Groupe d'étude des Tumeurs Endocrines (GTE)

Wermer's syndrome or Multiple Endocrine Neoplasia Type-1 (MEN1) is an autosomal dominant inherited disease, related to mutations in MEN1, an approximately 10-kb gene encoding menin, localized on chromosome 11q13. The Endocrine Tumor Group (GTE) has set up a MEN1 observatory of 1001 regularly followed MEN1 cases. This observatory aims at registering and evaluating MEN1 cases in a large cohort. Any new study on a particular unexplored aspect of the disease may be proposed by a physician to the GTE. This article describes the way to diagnose a new MEN1 case and to register it. Procedures for participating in a new study are presented. Some original results are quoted.

Prospective endoscopic ultrasonographic evaluation of the frequency of nonfunctioning pancreaticoduodenal endocrine tumors in patients with multiple endocrine neoplasia type 1

BACKGROUND

The frequency of pancreaticoduodenal endocrine tumors in patients with multiple endocrine neoplasia type 1 (MEN1) remains unknown.

AIM

To evaluate prospectively with endoscopic ultrasonography (EUS) the frequency of nonfunctioning (asymptomatic) pancreaticoduodenal tumors.

PATIENTS AND METHODS

MEN1 patients without functioning pancreatic involvement underwent systematic pancreaticoduodenal EUS in nine GTE (Groupe des Tumeurs Endocrines) centers. Demographic and clinical factors predictive of pancreatic involvement were sought, and standardized biochemical measurements obtained.

RESULTS

Between November 1997 and July 2004, 51 patients (median age: 39 [range: 16-71] yr) were studied. MEN1 had been diagnosed 3 [0-20] yr earlier, notably by genetic screening for 26 (51%) with asymptomatic disease. Twenty-five patients had minor biochemical anomalies (<2 x normal (N)) and serum somatostatin was 10.8 N in 1; EUS detected pancreatic lesions in 28 patients (54.9%; 95% CI: 41.3-68.7%). A median of three [1-9] tumors with a median diameter of 6 [2-60] mm was found per patient; for 19 (37.3%) patients a tumor measured > or =10 mm and > or = 20 mm in 7 (13.7%) patients. Only one duodenal lesion was found and three patients had peripancreatic adenopathies. Pancreatic tumors were not associated with any of the studied parameters, notably age, family history, biochemical anomalies. Sixteen of twenty-six patients underwent EUS monitoring over 50 [12-70] months; six (37.5%) had more and/or larger pancreatic lesions.

CONCLUSION

The frequency of nonfunctioning pancreatic endocrine tumors is higher (54.9%) than previously thought. The size and number of these tumors can increase over time. Pancreatic EUS should be performed once MEN1 is diagnosed to monitor disease progression.

Prevalence, characteristics and prognosis of MEN 1-associated glucagonomas, VIPomas, and somatostatinomas: study from the GTE (Groupe des Tumeurs Endocrines) registry

Few studies have concerned the rare functioning endocrine pancreatic tumors associated with multiple endocrine neoplasia type 1 (MEN 1). When sporadic, these tumors have a poor prognosis.

AIM

To analyze the frequency, characteristics and prognosis of MEN 1-associated glucagonomas, VIPomas and somatostatinomas recorded in the GTE (Groupe des Tumeurs Endocrines) registry.

METHODS

Records of the patients whose GTE registry codes included glucagonoma, VIPoma or somatostatinoma were reviewed. The diagnosis was confirmed when there were clinical signs of a functioning tumor and/or when blood levels of the peptide were higher than twice the upper limit of normal.

RESULTS

Among 580 patients with MEN 1, duodeno-pancreatic involvement was present in 307 (52.9%). Five (1.6%) had a glucagonoma, 3 (0.98%) a VIPoma and 2 (0.65%) a somatostatinoma. A clinical syndrome was present in 1 patient with glucagonoma, in the 3 with VIPomas and in 1 with somatostatinoma. Tumor size was greater than 3 cm more often for these rare tumours (67%) than in patients with other type of duodeno-pancreatic involvement (28%) (P=0.02) and visceral metastases were more frequent (40% vs 15%; P=0.056). Ten-year survival of patients with glucagonomas, VIPomas or somatostatinomas (53.8%; CI95%: 15.5-92.1) was poorer than that of patients with insulinomas (91.4%; CI95%: 83.399.5; P=0.01) or gastrinomas (81.7%; CI95%: 74.9-88.5; P=0.20) and close to that of patients with non-functioning tumors (62.2%, CI95%: 41.0-83.9; NS).

CONCLUSION

Glucagonomas, VIPomas and somatostatinomas, especially the functioning type, are very rare in patients with MEN 1. Prognosis is poor, probably because of large tumor size and high rate of metastasis. Survival is similar to that in patients with non-functioning tumors.

Current concepts in functioning endocrine tumors of the pancreas

Duodenal and pancreatic endocrine tumors are uncommon and their surgical treatment is often difficult. The management of these tumors has changed with recent advancements in tumor localization, intraoperative hormone measurements, standardized surgical techniques, and a better understanding of the genetic basis of multiple endocrine neoplasia syndrome. We present our experience with 191 endocrine tumors and elaborate the contemporary management of functioning duodenopancreatic endocrine tumors.

[Genetically-driven or supposed genetic-related insulinomas in adults: validation of the surgical strategy proposed by the A.F.C.E./G.E.N.E.M]

Between 1971 and 2002, 80 patients underwent surgery for insulinoma at the Department of General and Endocrine Surgery of the Lille University Hospitals. The present report deals with 13 patients with proven multiple endocrine neoplasia type I (MEN I) or supposed genetic-related insulinomas. This entity differs from spontaneous insulinoma by the presence of multiple foci in the pancreas. Enucleation is not advised in this setting due to the strong likelihood of persistence or recurrence. Various studies suggest different strategies for preoperative localization and surgical approach. We analyzed retrospectively the surgical strategy proposed by the A.F.C.E. and G.E.N.E.M. The purpose of this study was to validate the strategy, integrate the contribution of genotypic diagnosis, simplify preoperative imaging studies, and re-evaluate the value of intraoperative baseline secretin-stimulated insulin measurements. We recommend preoperative endoscopic ultrasonography of the pancreatic head only and routine left pancreatectomy with enucleation of cephalic tumors under intraoperative hormone monitoring. Preoperative invasive localization studies are proposed only if the endoscopic ultrasonography is negative for the pancreatic head. Intraoperative secretin stimulation test can be useful in difficult cases, especially with concurrent nesidioblastosis or in case of secondary surgery. All but one of the 13 patients achieved long-term cure with this strategy.

[Multiple endocrine neoplasia type I or Werner syndrome. What is important to know about surgery of a rate disease]

Multiple endocrine neoplasia type 1 (MEN1) is a rare but misleading disease. The diagnosis is evocated when two main lesions are present (parathyroid, endocrine pancreas, pituary gland) but also when a family tree shows recurrent lesions. Other lesions must be taken into account (adrenal glands, neuroendocrine thymic or bronchic lesions, cutaneous lesions, lipomas, nervous central system tumors). Any surgical cure without knowing the MEN1 background leads to failure. Specific treatment of each lesion is reviewed. Genetic diagnosis is possible but the mutation is not found in all cases. Nevertheless, when the mutation is known in a family, a negative genetic test allows to exclude the disease. Prognosis is related to hepatic metastases and to thymic neuroendocrine tumors which are rare (2.1%) but aggressive. As a general rule, any apparently isolated endocrine lesion such hyperparathyroidism must prompt the surgeon to look for another endocrine lesion and to look for an abnormal family tree with recurent monoglandular or pluriglandular lesions.

Multiple endocrine neoplasia type I

Multiple endocrine neoplasia type I is a rare autosomal dominant disorder with many endocrine and nonendocrine manifestations. Hyperparathyroidism, islet cell tumors, and pituitary tumors are diagnosed most commonly in these patients. There is controversy regarding treatment of the different manifestations and screening modalities of this disorder because no large series has determined the best therapeutic approach. Our institution advocates early screening with biochemical and radiographic testing in patients with a definite predilection for this disorder. Patients with hyperparathyroidism should undergo early surgical intervention of at least three and a half glands combined with bilateral upper thymectomy through a cervical incision. Although the recurrence rate is high, disease-free survival can be for as long as 30 years. Pituitary tumors are predominantly prolactinomas and growth hormone-releasing tumors. Prolactinomas usually require pharmacologic therapy, whereas growth hormone-releasing tumors are treated surgically. Enteropancreatic tumors should be treated surgically or medically, depending on the hormone secreted. Insulinomas respond well to distal pancreatectomy, with enucleation of the tumor from the head and uncinate process of the pancreas. However, there is controversy regarding the surgical treatment of gastrinomas. Carcinoid tumors should be treated with early surgical intervention. Adrenal lesions are thought to occur in association with pancreatic lesions and commonly have an indolent course. Adrenocortical cancers are uncommon in patients with multiple endocrine neoplasia type I. Skin lesions can be excised when cosmetically unappealing.

[Is preoperative localization of insulinomas necessary?]

STUDY AIM

To appreciate the impact of preoperative localization in surgical treatment of insulinomas.

PATIENTS AND METHOD

From 1986 to 2001, 29 patients were surgically treated for suspected insulinoma. Preoperative imaging assessment was performed in 26 patients: ultrasonography (n = 21), computed tomography (n = 23), endoscopic ultrasonography (n = 13), intraoperative ultrasonography (n = 22) (2 of them under laparoscopic approach).

RESULTS

The sensibility of the localization procedures was as follows: ultrasonography = 9.6%, computed tomography = 39%, endoscopic ultrasonography = 92.3%, surgical exploration 79.3%, intraoperative ultrasonography 86.3%. The sensibility of intraoperative palpation associated which intraoperative ultrasonography was 100%. Surgical procedures included: 11 enucleations, 10 segmental resections of the tail, 1 left pancreatectomy, 3 median pancreatectomies, 4 subtotal pancreatectomies. There was no postoperative mortality and postoperative morbidity rate was 17%, including 4 pancreatic leakages. Histological examination found solitary tumor in 22 patients (1 of them was a malignant tumor), multiple tumors (MEN 1) in 4 patients and factitious hypoglycemia in 3 patients. All the insulinomas were resected.

CONCLUSION

Intraoperative evaluation of the pancreas with intraoperative ultrasonography was associated which a right localization in 100% of insulinomas. The place for preoperative imaging seems to be limited. A laparoscopic approach in sporadic insulinomas could modify this attitude.

[Endocrine tumors of the duodenum and pancreas: "prerequisites", imaging, and intraoperative detection]

Non-secreting pancreatic neuroendocrine tumors and diarrheogenic tumors are usually bulky and easy to recognize thanks to somatostatin-receptor scintigraphy and hormonal dosages. The real difficulty concerns insulinomas and particularly gastrinomas, which are found at the level of the duodenum and can be very small. Diagnosis is based on biological examinations, and the search for MEN I must be done systematically. Their localization is based on two essential and noninvasive exams: echoendoscopy and somatostatin-receptor imaging, though the surgeon's skill in the operative field, aided by an intraoperioperative echography, is indispensable. Surgical treatment of insulinomas gives excellent results. However, for sporadic gastrinomas, there was only a 34% recovery rate, and still less for MEN I gastrinomas.