Duodenopancreatic resections in patients with multiple endocrine neoplasia type 1

Portuguese Pancreatic Club Perspectives on Endoscopic Ultrasound-Guided and Surgical Treatment of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (panNETs) are a group of neoplasms with heterogenous biological and clinical phenotypes. Although historically regarded as rare, the incidence of these tumors has been increasing, mostly owing to improvements in the detection of small, asymptomatic tumors with imaging. The heterogeneity of these lesions creates significant challenges regarding diagnosis, staging, and treatment. Endoscopic ultrasound (EUS) has improved the characterization of pancreatic lesions. Furthermore, EUS nowadays has evolved from a purely diagnostic modality to allow the performance of minimally invasive locoregional therapy for pancreatic focal lesions. The choice of treatment as well as the treatment goals depend on several factors, including tumor secretory status, grading, staging, and patient performance status. Surgery has been the mainstay for the management of these patients, particularly for localized, low-grade, large panNETs >2 cm. Over the last decade, a significant body of evidence has been accumulated evaluating the role of EUS for the ablative therapy of panNETs, namely by the use of chemoablative agents and radiofrequency. Although endoscopic techniques are not routinely recommended by international guidelines, they may be considered for the treatment of smaller lesions in patients who are unwilling or unfit for pancreatic surgery. In this review, we summarize the existing evidence on the interventional techniques for the treatment of patients with panNETs, focusing on the EUS-guided and surgical approaches.

[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.

Pancreatic Neuroendocrine Tumors in MEN1 Patients: Difference in Post-Operative Complications and Tumor Progression between Major and Minimal Pancreatic Surgeries

Pancreatic neuroendocrine neoplasms (PNENs) affect over 80% of patients with multiple endocrine neoplasia type 1 (MEN1). Surgery is usually the therapy of choice, but the real immediate and long-term therapeutic benefit of a partial extensive pancreatic resection remains controversial. We analyzed, in 43 PNEN MEN1 patients who underwent 19 pancreaticoduodenectomies (PD), 19 distal pancreatectomies (DP), and 5 minimal pancreatectomies, the prevalence of surgery-derived early complications and post-operative pancreatic sequelae, and the PNEN relapse-free survival time after surgery, comparing major (PD+DP) and minimal pancreatic surgeries. No post-operative mortality was observed. Metastatic cancers were found in 12 cases, prevalently from duodenal gastrinoma. Long-term cure of endocrine syndromes, by the 38 major pancreatic resections, was obtained in 78.9% of gastrinomas and 92.9% of insulinomas. In only one patient, hepatic metastases, due to gastrinoma, progressed to death. Out of the 38 major surgeries, only one patient was reoperated for the growth of a new PNEN in the remnant pancreas. No functioning PNEN persistence was reported in the five minimal pancreatic surgeries, PNEN relapse occurred in 60% of patients, and 40% of cases needed further pancreatic resection for tumor recurrence. No significant difference in PNEN relapse-free survival time after surgery was found between major and minimal pancreatic surgeries.

Pancreaticoduodenectomy Is the Best Surgical Procedure for Zollinger-Ellison Syndrome Associated with Multiple Endocrine Neoplasia Type 1

Simple Summary

Approximately 30% of patients with multiple endocrine neoplasia type 1 (MEN1) develop the Zollinger–Ellison syndrome (ZES), caused by solitary or multiple duodenal gastrinomas. Its management, especially regarding indication, timing, and type of surgery, is highly controversial. Therefore, the present study evaluated the long-term outcomes of pancreaticoduodenectomy (PD) versus non-PD resections in MEN1-ZES with regard to biochemical cure and quality of life. We found in a series of 35 patients that initial PD is the superior surgical procedure for MEN1-ZES, leading to long-term cure in about 80% of patients, fewer duodenopancreatic reoperations and an acceptable quality of life. Based on the results of this study, MEN1-ZES should be considered a surgically curable disease.

Abstract

Aim: The aim of this research was to evaluate the long-term outcome of pancreaticoduodenectomy (PD) versus other duodenopancreatic resections (non-PD) for the surgical treatment of the Zollinger–Ellison syndrome (ZES) in patients with multiple endocrine neoplasia type 1 (MEN1). Methods: Prospectively recorded patients with biochemically confirmed MEN1-ZES who underwent duodenopancreatic surgery were retrospectively analyzed in terms of clinical characteristics, complications, cure rate, and long-term morbidity, including quality of life assessment (EORTC QLQ-C30). Results: 35 patients (16 female, 19 male) with MEN1-ZES due to duodenopancreatic gastrinomas with a median age of 42 (range 30–74) years were included. At the time of diagnosis, 28 (80%) gastrinomas were malignant, but distant metastases were only present in one (3%) patient. Eleven patients (31.4%) underwent pancreatoduodenectomy (PD) as the initial procedure, whereas 24 patients underwent non-PD resections involving duodenotomy with gastrinoma excision, enucleation of the pNEN from the head of the pancreas, and peripancreatic lymphadenectomy, either with or without distal pancreatectomy (i.e., either Thompson procedure, n = 12, or DUODX, n = 12). There was no significant difference in perioperative morbidity and mortality between the two groups (p ≥ 0.05). One (9%) patient of the PD group required reoperation for recurrent or metastatic ZES compared to eight (22.8%) patients of the non-PD resection groups. After a median follow-up time of 134 months (range 6–480) nine of 11 (82%) patients in the PD group, two of 12 (16%) patients in the Thompson procedure group, and three of 12 (25%) patients in the DUODX group had normal serum gastrin levels. In addition, the global health QoLScore was better in the PD group (76.9) compared to the Thompson procedure (57.4) and DUODX (59.5) groups. Conclusions: Initial PD seems to be the superior surgical procedure for MEN1-ZES, resulting in a long-term cure rate of about 80%, fewer duodenopancreatic reoperations, and an acceptable quality of life.

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.

Long-term outcomes in MEN-1 patients with pancreatic neuroendocrine neoplasms: an Israeli specialist center experience

PURPOSE

The decreased life expectancy of MEN-1 patients is mainly related to pancreatic neuroendocrine tumors (pNETs). At best, limited data is available on the natural history of MEN-1-associated pNETs, as these tumors are rare and have a wide range of biologic behavior. Our study aims to explore the clinical course of patients with MEN-1-associated pNETs and the long-term outcomes.

METHODS

This longitudinal study was conducted on the MEN-1 cohort treated at our referral center over a 22-year period (1996-2018). Relevant clinical data were retrospectively analysed.

RESULTS

Among the 33 MEN-1 patients included in our study, pNETs were identified in 21 subjects with a penetrance of 48% by the age of 50. Non-functioning and functioning pNETs were diagnosed in sixteen (76%) and five (24%) patients, respectively. Two-thirds of the patients had multifocal tumors. The median number of pancreatic macroscopic lesions per individual was 4.0 ± 3.9 (range 1-8) with a mean size of 1.3 ± 2.1 cm (range 0.5-10). The metastatic rate according to the dominant pNET lesion reached 100%, 62% and 6% for tumors sized > 4 cm, 2.1-4 cm, and 1-2 cm, respectively. Over the study period, one or more therapeutic interventions for pNETs were required in 20 out of the 21 patients. pNET-related metastatic complication was the main cause of death within this MEN-1 cohort. The overall survival rate for the pNETs patients was 86% during a mean follow-up period of 8.0 ± 4.6 years.

CONCLUSIONS

In our MEN-1 cohort, non-functioning pNETs were the most frequent type of pancreaticoduodenal tumor, and the tumor size correlated with the risks of metastasis and death. Increased awareness, early diagnosis, and a multidisciplinary approach may improve the associated morbidity and mortality in these patients.

The North American Neuroendocrine Tumor Society Consensus Paper on the Surgical Management of Pancreatic Neuroendocrine Tumors

This manuscript is the result of the North American Neuroendocrine Tumor Society consensus conference on the surgical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The group reviewed a series of questions of specific interest to surgeons taking care of patients with pancreatic neuroendocrine tumors, and for each, the available literature was reviewed. What follows are these reviews for each question followed by recommendations of the panel.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

OBJECTIVE

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Pancreatic Neuroendocrine Tumors (panNETs): Analysis of Overall Survival of Nonsurgical Management Versus Surgical Resection

BACKGROUND

Outcomes of patients with pancreatic neuroendocrine tumors (panNETs) undergoing surgical or nonsurgical management and outcomes of enucleation versus standard resection were compared.

METHODS

MEDLINE, EMBASE, PubMed, Scopus, and Cochrane were queried (2000 to present). All studies comparing patients undergoing surgical versus nonsurgical treatments, or enucleation versus standard resection, were included. Pooled risk ratios and 95% CI for survival were calculated.

RESULTS

Eleven studies met criteria with 1491 resected and 1607 nonsurgically managed patients. Meta-analysis showed improved overall survival with resection at 1 year (risk ratio (RR) = 1.281, CI 1.064-1.542, p = 0.009), 3 years (RR = 1.837, CI 1.594-2.117, p < 0.001), and 5 years (RR = 2.103, CI 1.50-2.945, p < 0.001). OS of patients with resected nonfunctioning panNETs was improved at 3 years (RR = 1.847, CI 1.477-2.309, p < 0.001) and 5 years (RR = 1.767, CI 1.068-2.924, p = 0.027). OS was improved when panNETs ≤2 cm were resected at 3 years (RR = 1.695, CI 1.269-2.264, p < 0.001) and 5 years (RR = 2.210, CI 1.749-2.791, p < 0.001). Fifteen articles met criteria for enucleation versus standard resection (n = 1035; 620 were nonfunctioning). Enucleation had shorter operative time (weighted mean difference (WMD) = -95.6 min, 95% CI -131.4 to -59.8, p < 0.01), less operative blood loss (WMD = -172.6 ml, 95% CI -340 to -5.1, p = 0.04), but increased postoperative pancreatic fistula (POPF) (RR = 2.08, 95% CI 1.39-3.12, p < 0.01).

CONCLUSION

Surgical resection of panNETs, including small and nonfunctioning, appears to be associated with improved OS. Enucleation is associated with shorter operative time, less blood loss, but greater incidence of POPF. Prospective, randomized clinical trials are needed to confirm these results.

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.

Partial pancreaticoduodenectomy can provide cure for duodenal gastrinoma associated with multiple endocrine neoplasia type 1

OBJECTIVE

To evaluate the outcome of pancreaticoduodenectomy (PD) versus non-PD resections for the treatment of gastrinoma in multiple endocrine neoplasia type 1.

BACKGROUND

Gastrinoma in MEN1 is considered a rarely curable disease and its management is highly controversial both for timing and extent of surgery.

METHODS

Clinical characteristics, complications and outcomes of 27 prospectively collected MEN1 patients with biochemically proven gastrinoma, who underwent surgery, were analyzed with special regard to the gastrinoma type and the initial operative procedure.

RESULTS

Twenty-two (81%) patients with gastrinoma in MEN1 had duodenal gastrinomas and 5 patients (19%) had pancreatic gastrinomas. At the time of diagnosis, 21 (77%) gastrinomas were malignant (18 duodenal, 3 pancreatic), but distant metastases were only present in 4 (15%) patients. Patients with pancreatic gastrinomas underwent either distal pancreatic resections or gastrinoma enucleation with lymphadenectomy, 2 patients also had synchronous resections of liver metastases. One of these patients was biochemically cured after a median of 136 (77-312) months. Thirteen patients with duodenal gastrinomas underwent PD resections (group 1, partial PD [n = 11], total PD [n = 2]), whereas 9 patients had no-PD resections (group 2) as initial operative procedure. Perioperative morbidity and mortality, including postoperative diabetes, differed not significantly between groups (P > 0.5). All patients of group 1 and 5 of 9 (55%) patients of group 2 had a negative secretin test at hospital discharge. However, after a median follow-up of 136 (3-276) months, 12 (92%) patients of group 1 were still normogastrinemic compared to only 3 of 9 (33%) patients of group 2 (P = 0.023). Three (33%) patients of group 2 had to undergo up to 3 reoperations for recurrent or metastatic disease compared to none of group 1.

CONCLUSIONS

Duodenal gastrinoma in MEN1 should be considered a surgically curable disease. PD seems to be the adequate approach to this disease, providing a high cure rate and acceptable morbidity compared to non-PD resections.

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.

Surgical management of insulinomas in multiple endocrine neoplasia type 1

OBJECTIVE

This study aimed to evaluate the accuracy of preoperative and intraoperative diagnostic tools and the surgical strategy to obtain cure in multiple endocrine neoplasia type 1 (MEN-1) patients affected with insulinoma.

METHODS

Eight MEN-1 patients (1992-2009) were operated on for hypoglycemic crisis. Preoperative tumor localization was carried out. Ultrasound and modification of the insulin/glucose (I/G) ratio were applied intraoperatively. Pancreatic lesions larger than 0.5 cm were removed by resection of the most affected pancreatic region and by enucleation of nodules in least affected regions.

RESULTS

Two pancreatoduodenectomies and 6 distal pancreatectomies were performed; enucleation of nodules was necessary in 6 patients. There was no postoperative mortality. At the histopathologic analysis, a mean of 6 macrotumors and of 15.5 microlesions were found. Intraoperative ultrasound proved a sensitivity of 87.5% for detecting pancreatic insulinoma. Decrease in the I/G ratio after resection predicted postoperative outcome in all patients. At a mean follow-up of 81.5 months, all patients were normoglycemic with no evidence of disease recurrence.

CONCLUSIONS

Multiple endocrine neoplasia type 1 insulinomas should be considered surgically curable. Pancreatic resection seems preferable to a less radical surgical approach in ensuring higher cure rates. Intraoperative ultrasound and I/G ratio are of value in the assessment of surgical decision and in the evaluation of the surgical cure.

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.

Diagnosis and Treatment of Gastrinomas in Multiple Endocrine Neoplasia Type 1 (MEN-1)

Multiple endocrine neoplasia type 1 (MEN-1) is a rare autosomal-dominant disease. It is associated with a broad range of endocrine tumours, most frequently arising in the parathyroid glands, the pituitary and the pancreas. Most neuroendocrine tumours will be diagnosed in the pancreas as non-functioning neuroendocrine tumours or insulinomas. Forty-two percent of the patients will develop a gastrin-secreting neuroendocrine tumour, a gastrinoma. Gastrinomas in MEN-1 tend to be small, multiple and preferentially located in the duodenum. This paper will focus on the specific characteristics of gastrinomas in the setting of MEN-1 compared to sporadic gastrinomas. The developments in understanding the tumorigenesis of these tumours and the consequences for diagnosis and therapy will be discussed.

Surgical management of pancreatico-duodenal tumors in multiple endocrine neoplasia syndrome type 1

Pancreatico-duodenal tumors are the second most common endocrinopathy in multiple endocrine neoplasia syndrome type 1, and have a pronounced effect on life expectancy as the principal cause of disease-related death. Previous discussions about surgical management have focused mainly on syndromes of hormone excess and, in particular, the management of multiple endocrine neoplasia syndrome type 1-related Zollinger-Ellison syndrome. Since hormonal syndromes tend to occur late and indicate the presence of metastases, screening with biochemical markers and endoscopic ultrasound is recommended for early detection of pancreatico-duodenal tumors, and with early surgery before metastases have developed. Surgery is recommended in patients with or without hormonal syndromes in the absence of disseminated liver metastases. The suggested operation includes distal 80% subtotal pancreatic resection together with enucleation of tumors in the head of the pancreas, and in cases with Zollinger-Ellison syndrome, excision of duodenal gastrinomas together with clearance of regional lymph node metastases. This strategy, with early and aggressive surgery before metastases have developed, is believed to reduce the risks for tumor recurrence and malignant progression.

Long-term results of surgery for pancreatic neuroendocrine neoplasms in patients with MEN1

PURPOSE

This study was made to evaluate long-term results of an aggressive surgical approach for pancreaticoduodenal neuroendocrine neoplasms (pNENs) in patients with multiple endocrine neoplasia type 1 (MEN1).

METHODS

MEN1 patients with either biochemical evidence of functioning or non-functioning pNENs larger than 1 cm in size on imaging underwent duodenopancreatic surgery. Since 1997, patients were followed annually by biochemical testing and imaging studies.

RESULTS

Thirty-eight genetically confirmed MEN1 patients underwent duodenopancreatic resection for functioning (n = 22) or non-functioning (n = 16) pNENs, nine patients were yet not operated. Malignant disease occurred in 12 (35%) patients defined by either lymph node (12 patients) and/or distant metastases (2 patients). Six patients with Zollinger-Ellison syndrome (ZES) required pylorus-preserving pancreaticoduodenectomy (PPPD) as initial or redo procedure and 32 patients underwent other duodenopancreatic resections. Ten (26%) patients underwent up to four reoperations for either recurrent or metastatic disease that resulted in completion pancreatectomy in four patients. After median 109 months, 44 patients were alive and three patients died, one due to thymic carcinoid and two of unrelated causes. All eight patients with organic hyperinsulinism and 7 of 13 patients with ZES were biochemically cured. However, 24 of 38 (78%) patients developed new pNENs in the pancreatic remnant, but none developed distant metastases.

CONCLUSIONS

Early resection of pNENs in MEN1 may prevent the development of distant metastases. However, the majority of patients develop new pNENs in the duodenopancreatic remnant which may require completion pancreatectomy in the long term.

Biochemically curative surgery for gastrinoma in multiple endocrine neoplasia type 1 patients

AIM: To search for the optimal surgery for gastrinoma and duodenopancreatic neuroendocrine tumors in patients with multiple endocrine neoplasia type 1.

METHODS: Sixteen patients with genetically confirmed multiple endocrine neoplasia type 1 (MEN 1) and Zollinger-Ellison syndrome (ZES) underwent resection of both gastrinomas and duodenopancreatic neuroendocrine tumors (NETs) between 1991 and 2009. For localization of gastrinoma, selective arterial secretagogue injection test (SASI test) with secretin or calcium solution was performed as well as somatostatin receptor scintigraphy (SRS) and other imaging methods such as computed tomography (CT) or magnetic resonance imaging (MRI). The modus of surgery for gastrinoma has been changed over time, searching for the optimal surgery: pancreaticoduodenectomy (PD) was first performed guided by localization with the SAST test, then local resection of duodenal gastrinomas with dissection of regional lymph nodes (LR), and recently pancreas-preserving total duodenectomy (PPTD) has been performed for multiple duodenal gastrinomas.

RESULTS: Among various types of preoperative localizing methods for gastrinoma, the SASI test was the most useful method. Imaging methods such as SRS or CT made it essentially impossible to differentiate functioning gastrinoma among various kinds of NETs. However, recent imaging methods including SRS or CT were useful for detecting both distant metastases and ectopic NETs; therefore they are indispensable for staging of NETs. Biochemical cure of gastrinoma was achieved in 14 of 16 patients (87.5%); that is, 100% in 3 patients who underwent PD, 100% in 6 patients who underwent LR (although in 2 patients (33.3%) second LR was performed for recurrence of duodenal gastrinoma), and 71.4% in 7 patients who underwent PPTD. Pancreatic NETs more than 1 cm in diameter were resected either by distal pancreatectomy or enucleations, and no hepatic metastases have developed postoperatively. Pathological study of the resected specimens revealed co-existence of pancreatic gastrinoma with duodenal gastrinoma in 2 of 16 patients (13%), and G cell hyperplasia and/or microgastrinoma in the duodenal Brunner’s gland was revealed in all of 7 duodenal specimens after PPTD.

CONCLUSION: Aggressive resection surgery based on accurate localization with the SASI test was useful for biochemical cure of gastrinoma in patients with MEN 1.

[About a case of multiple endocrine neoplasia type 1. Review of some clinical manifestations and treatment controversies]

The rare hereditary syndrome, multiple endocrine neoplasia type1 (MEN-1), is known to predispose affected individuals to endocrine neoplasms in a variety of tissues such as the parathyroid glands, the pituitary gland and the gastrointestinal tract. We describe the case of a man with traditionally-described manifestations (hyperparathyroidism and gastrinoma) and with other tumoral lesions arising from endocrine cells (insulinoma, gastric carcinoid, adrenal adenoma and pancreatic non-functioning neuroendocrine tumors) and non-endocrine cells (lipoma and collagenoma). Frequent recurrences in susceptible tissues that are not totally removed (as occurs in hyperparathyroidism and duodenal gastrinoma) and their unknown clinical significance have aroused current controversies in the therapeutic management of these entities, which is briefly reviewed.

Bilateral adrenocortical carcinoma in a patient with multiple endocrine neoplasia type 1 (MEN1) and a novel mutation in the MEN1 gene

The incidence of adrenal involvement in MEN1 syndrome has been reported between 9 and 45%, while the incidence of adrenocortical carcinoma (ACC) in MEN1 patients has been reported between 2.6 and 6%. In the literature data only unilateral development of ACCs in MEN1 patients has been reported. We report a 31 years-old female MEN1-patient, in whom hyperplasia of the parathyroid glands, prolactinoma, non functioning pancreatic endocrine carcinoma and functioning bilateral adrenal carcinomas were diagnosed. Interestingly, a not previously described in the literature data, novel germline mutation (p.E45V) in exon 2 of MEN1 gene, was detected. The association of exon 2 mutation of the MEN1 gene with bilateral adrenal carcinomas in MEN1 syndrome, should be further investigated.

Diagnosis and management of pancreatic neuroendocrine tumor in von Hippel-Lindau disease

The pancreatic manifestations seen in patients with von Hippel-Lindau (VHL) disease are subdivided into 2 categories: pancreatic neuroendocrine tumors (NET), and cystic lesions, including simple cyst and serous cystadenoma. The VHL-associated cystic lesions are generally asymptomatic and do not require any treatment, unless they are indistinguishable from other cystic tumor types with malignant potential. Because pancreatic NET in VHL disease are non-functioning and have malignant potential, it is of clinical importance to find and diagnose these as early as possible. It will be recommended that comprehensive surveillance using dynamic computed tomography for abdominal manifestations, including pancreatic NET, should start from the age of 15 years in VHL patients. Unlike sporadic non-functioning NET without VHL disease, in which surgical resection is generally recommended, VHL patients at lower metastatic risk of pancreatic NET should be spared the risks of operative resection.

Surgical management of MEN-1 and -2: state of the art

Multiple endocrine neoplasia syndrome type 1 (MEN-1) consists of endocrine tumors of the parathyroid, the endocrine pancreas-duodenum, and the pituitary. Surveillance and screening for the endocrinopathies is recommended in gene carriers. Surgery for MEN-1-related hyperparathyroidism is generally performed as radical subtotal parathyroidectomy, because less surgery is likely to result in persistent or recurrent disease. Multiple endocrine neoplasia syndrome type 2 (MEN-2) consists of medullary thyroid carcinoma, pheochromocytoma, and hyperparathyroidism. Prophylactic thyroidectomy based on DNA testing in the MEN-2 syndrome is considered one of the greater achievements in cancer treatment, because it may be performed before thyroid carcinoma development and provides cure for the patient.

Asymptomatic children with multiple endocrine neoplasia type 1 mutations may harbor nonfunctioning pancreatic neuroendocrine tumors

CONTEXT

Multiple endocrine neoplasia type 1 (MEN1) is characterized by the occurrence of parathyroid, pituitary, and pancreatic tumors. MEN1, an autosomal dominant disorder, has a high degree of penetrance, such that more than 95% of patients develop clinical manifestations by the fifth decade, although this is lower at approximately 50% by age 20 yr. However, the lower penetrance in the younger group, which is based on detecting hormone-secreting tumors, may be an underestimate because patients may have nonfunctioning tumors and be asymptomatic.

OBJECTIVE

The aim of the study was to evaluate the occurrence of nonfunctioning pancreatic neuroendocrine tumors in asymptomatic children with MEN1.

PATIENTS

Twelve asymptomatic Northern European children, aged 6 to 16 yr, who were known to have MEN1 mutations were studied.

RESULTS

Two asymptomatic children, who were aged 12 and 14 yr, had normal plasma fasting gastrointestinal hormones and were found to have nonfunctioning pancreatic neuroendocrine tumors that were more than 2 cm in size. Surgery and immunostaining revealed that the tumors did not have significant expression of gastrointestinal hormones but did contain chromogranin A and synaptophysin, features consistent with those of nonfunctioning pancreatic neuroendocrine tumors. The tumors had a loss of menin expression. The 14 yr old also had primary hyperparathyroidism and a microprolactinoma, and the 12 yr old had a nonfunctioning pituitary microadenoma. Three other children had primary hyperparathyroidism and a microprolactinoma.

CONCLUSION

Nonfunctioning pancreatic neuroendocrine tumors may occur in asymptomatic children with MEN1 mutations, and screening for such enteropancreatic tumors in MEN1 children should be considered earlier than the age of 20 yr, as is currently recommended by the international guidelines.

Long-Term Results of a Selective Surgical Approach to Management of Zollinger-Ellison Syndrome in Patients with MEN-1

The role of operation in patients with Multiple Endocrine Neoplasia Type 1 (MEN-1) and Zollinger-Ellison Syndrome (ZES) is controversial. Our institutional bias for this disease has, in general, been towards aggressive imaging and operative removal of localized gastrinomas. Few studies have reported long-term outcomes in patients with MEN-1 and ZES. A single institution retrospective review of all patients with MEN-1 and ZES from 1970 to present was performed. Twelve patients were identified (median age = 37 years at diagnosis). The median follow-up was 18 years from diagnosis of ZES. Common symptoms associated with gastrinoma in these patients were diarrhea (n = 6), abdominal pain (n = 4), and nausea/vomiting (n = 4). Most commonly identified sites of gastrinoma were: pancreas (n = 10), duodenum (n = 4), lymph nodes (n = 3), and liver (n = 1). Fifteen celiotomies were performed in total (median = 1; range 0-3). Operative procedures performed included: distal pancreatectomy (n = 4), acid reducing procedure (n = 4), enucleation of pancreatic gastrinoma (n = 3), duodenal resection (n = 3), pancreaticoduodenectomy (n = 1), and other (n = 7). One patient had a transient biochemical cure after operation lasting 3 years. Only one patient in this series had documented liver metastases of gastrinoma and no patients expired of metastatic gastrinoma. There was one postoperative patient death, secondary to respiratory arrest thought to be a result of aspiration or pulmonary embolus. Three patients died of nondisease related causes, and seven patients were alive at the time of last follow-up. Operations rarely result in biochemical cures in patients with MEN-1 and ZES. In our experience, resection of localized gastrinomas often did not require extended surgical resection and were associated with excellent long-term outcomes.

Role of menin in neuroendocrine tumorigenesis

The menin protein encoded by the MEN1 tumor suppressor gene is ubiquitously expressed and highly conserved evolutionarily. The combination of findings from current in vitro and in vivo studies has not yielded a comprehensive understanding of the mechanisms of menin's tumor suppressor activity or the specific role for menin in endocrine tumorigenesis, although its diverse interactions suggest possible pivotal roles in transcriptional regulation, DNA processing and repair and cytoskeletal integrity. This manuscript summarizes recent research findings including studies of global gene expression in MEN1-associated neuroendocrine tumors and pivotal changes in intracellular signaling pathways associated with neuroendocrine tumorigenesis. Finally, the clinical applications provided by the understanding of the effects of MEN1 gene mutations on neuroendocrine tumor development in patients with this familial cancer syndrome are discussed.

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.

Multiple endocrine neoplasia syndromes

The multiple endocrine neoplasia (MEN) syndromes are rare autosomal-dominant conditions that predispose affected individuals to benign and malignant tumors of the pituitary, thyroid, parathyroids, adrenals, endocrine pancreas, paraganglia, or nonendocrine organs. The classic MEN syndromes include MEN type 1 and MEN type 2. However, several other hereditary conditions should also be considered in the category of MEN: von Hippel-Lindau syndrome, the familial paraganglioma syndromes, Cowden syndrome, Carney complex, and hyperparathyroidism jaw-tumor syndrome. In addition, researchers are becoming aware of other familial endocrine neoplasia syndromes with an unknown genetic basis that might also fall into the category of MEN. This article reviews the clinical features, diagnosis, and surgical management of the various MEN syndromes and genetic risk assessment for patients presenting with one or more endocrine neoplasms.

Multiple endocrine neoplasia

MEN1 and MEN2 are autosomal dominant cancer syndromes with the potential for considerable morbidity and mortality. Better understanding of the molecular pathogenesis in MEN1 and MEN2 has fostered the development of specific DNA screening. Knowing the genetic status of patients is valuable for making decisions regarding surveillance and interventions, such as prophylactic thyroidectomy for medullary thyroid cancer. Identifying new RET pathways has provided molecular targets for therapies that currently are being tested in clinical trials for locally advanced, metastatic, and recurrent medullary thyroid cancer.

Surgical aspects of gastrinoma in multiple endocrine neoplasia type 1

Gastrinoma is the most frequent functional pancreaticoduodenal endocrine tumor in patients with multiple endocrine neoplasia type 1 (MEN1) and one major determinant of mortality in this syndrome. Whether routine surgical exploration should be performed in a patient with MEN1 associated Zollinger-Ellison syndrome (ZES) to possibly reduce the malignant spread and eventually increase survival still remains controversial. There is not only disagreement about the indication for surgical exploration, but also what type of procedure should be performed, since sufficient evidence-based data are not available. The article discusses the available data on treatment strategies of MEN1 associated ZES.

Pancreatic neuroendocrine tumours

Pancreatic neuroendocrine tumours are rare tumours ( approximately 1/100,00 population/year) of which 60% are non-functioning. Except for insulinoma all types are malignant in >50% of cases. In multiple endocrine neoplasia (MEN)1, pancreatic neuroendocrine tumours occur in 40-80% of patients and are mostly non-functioning tumours or gastrinomas. Insulinomas are benign in approximately 90%, solitary in 95% of sporadic cases whilst multiple in 90% of MEN1 patients. In contrast approximately 50% gastrinomas and the majority of non-functioning pancreatic neuroendocrine tumours are malignant. Pancreatic neuroendocrine tumours occur in 10-15% of patients with Von Hippel-Lindau (VHL) and are frequently multiple (>30%). Surgical excision is a key aspect of treatment for all cases of sporadic gastrinoma and if >2.5 cm in MEN1. Insulinomas are enucleated if solitary and may require pancreatectomy if multiple. Non-functioning tumours should also be resected if sporadic and if >2 cm in MEN1 or if >2-3 cm in VHL. Tumours <1cm require yearly follow-up by CT or MRI from an early age in VHL. The local treatment for liver metastases is now well established and options include liver resection, chemoembolisation and radiofrequency ablation. Systemic therapies have also been better defined and include radionuclide therapy against somatostatin receptors or MIBG and chemotherapy especially for poorly differentiated tumours. A number of novel agents are currently in clinical development.

Pancreatoduodenal surgery in patients with multiple endocrine neoplasia type 1: Operative outcomes, long-term function, and quality of life

BACKGROUND

Pancreatoduodenal (PD) neoplasms represent the principal disease-specific lethality in multiple endocrine neoplasia type 1 (MEN1). Potential oncologic benefits of PD resection must be weighed against operative morbidities, compromised pancreatic function, and quality of life (QOL).

METHODS

Fifty MEN1 patients underwent PD resections during 1984-2004. Postoperative pancreatic function and QOL were assessed by EORTC QLQ-C30 and a disease-specific questionnaire (response rate, 78%).

RESULTS

Twelve patients (24%) had asymptomatic disease detected by screening; 38 patients (76%) were symptomatic. All gross neoplasm was resected in 80% of patients. No patients died; 21 patients (42%) had complications. At 5 years postoperatively, 60% of patients were alive without disease, 24% of patients were with disease, 10% of patients died of PD neoplasms, 4% of patients died of other malignancies, and 2% of patients died of an unknown cause. Diabetes that requires insulin or oral hypoglycemics developed in 20% of patients. Frequent steatorrhea (>once/week) occurred in 25% of patients, early dumping occurred in 25% of patients, bloating occurred in 25% of patients, late dumping occurred in 7% of patients, hypoglycemia occurred in 7% of patients, and vomiting occurred in 4% of patients. Global QOL did not differ from that of the reference population (72.8 vs 75.3; P = .58).

CONCLUSION

PD resections in MEN1 are associated with perioperative risks and altered pancreatic function. The moderate compromise in patient-perceived QOL suggests that most patients accept and adapt to these trade-offs for the potential of prolonged survival.

[Pancreatic incidentalomas. Correct assessment and therapy]

Due to recent advances in CT/MRI technology, incidentalomas of the pancreas are detected with increasing frequency. Pancreatic incidentalomas should be differentiated into solid and cystic tumors. In both subgroups definitive classification of the tumor is often not possible. Operative therapy is recommended in premalignant or malignant pathologies. Thus solid incidentalomas should be resected independently of their size, if the patient is without serious comorbidities. In case of cystic incidentalomas, benign cystic lesions should be excluded as far as possible. Otherwise they should be resected if their size is >or=2 cm. In case of IPMN with specific risk factors, resection is recommended when the tumor size exceeds 1 cm.

Long-term follow-up of patients with multiple endocrine neoplasia type 1

Whether early surgical treatment of non-functioning pancreas islet cell tumor (NFPT) provides a favorable quality of life and life expectancy in patients with multiple endocrine neoplasia type 1 (MEN1) remains controversial. We analyzed the long-term clinical courses and surgical outcomes of 14 Japanese patients with MEN1-associated NFPTs. NFPTs smaller than 20 mm in diameter did not show any apparent growth over a long monitoring period. Furthermore, these small NFPTs did not metastasize to regional lymph nodes or the liver. On the other hand, the development of additional NFPTs or metastasis was found in five of six patients with large (35 mm or larger) NFPTs. Among the seven patients who underwent a partial pancreatectomy, six patients developed impaired glucose tolerance or diabetes. The accumulation of more prospective data is needed to clarify the optimal surgical indications for patients with NFPTs, especially among the Japanese population, which has a relatively low insulin secretion potency compared with non-Hispanic white and African-American populations.

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

BACKGROUND

The management of small, nonfunctioning pancreaticoduodenal endocrine tumors (NFPET) in multiple endocrine neoplasia type 1 (MEN1) patients is still controversial. We therefore investigated the effect of surgery on survival and tumor progression in MEN1 patients with NFPET < or = 2 cm by analyzing data from the Groupe des Tumeurs Endocrines (GTE) registry.

MATERIALS AND METHODS

Among 579 MEN1 patients in the registry, 65 had NFPET < or = 2 cm. Fifteen (23%) underwent pancreatectomy, 9 at least segmental pancreatectomies and 6 biopsies or enucleations (the surgery group), and 50 (77%) were followed conservatively (the no surgery group). Age at MEN1 and NFPET diagnosis was similar in both groups, as was size of the primary tumor. Seven (10.8%) patients had metastases. Five metastases were synchronous, and 2 (one in each group) were metachronous. Tumor size was similar in patients with or without metastasis.

RESULTS

There was no perioperative mortality. The average follow-up time after NFPET diagnosis was 6.7 years in the surgery group and 3.3 years in the no surgery group. Three (4.6%) patients died during follow-up, 2 due to NFPET and 1 due to thymus tumor. The 2 patients who died of NFPET had undergone pancreatic surgery at the time of NFPET diagnosis. The 2 groups did not differ significantly with respect to tumor progression [5/15 (33%) vs 6/38 (16%), P = 0.16]. Overall life expectancy of patients with NFPET < or = 2 cm was not different than that of the 229 MEN1 patients in the registry without any pancreaticoduodenal tumor (P = 0.33).

CONCLUSIONS

This study suggests that surgery may not be beneficial for MEN1 patients with NFPET < or = 2 cm.

Management of pancreatic endocrine tumors in multiple endocrine neoplasia type 1

INTRODUCTION

Pancreatic endocrine tumors (PETs) occur in at least 50% of patients with multiple endocrine neoplasia type 1 (MEN1) and are the leading cause of disease-specific mortality. However, the timing and extent of surgery for MEN1-related PETs is controversial owing to the indolent tumor growth seen in most patients and the desire to avoid complications associated with insulin dependence. To help resolve this controversy, we retrospectively analyzed the clinical characteristics, surgical treatment, and clinical outcome of patients with MEN1-related PETs.

METHODS

All patients had histologic or radiographic confirmation of a PET in the setting of MEN1. Disease progression was defined radiographically as the development of new pancreatic tumors or distant metastases. Progression-free survival (PFS) and overall survival (OS) were used as the endpoints of this analysis.

RESULTS

We identified 98 patients with MEN1, 55 (56%) of whom had PETs, including 27 women and 28 men with a median age of 37 years (range 8-69 years) at the time of diagnosis. Functioning PETs were present in 35 (64%) of 55 patients, and nonfunctioning tumors were present in 20 (36%). Pancreatic surgery was performed in 38 (69%) of the 55 patients; and the first operation included enucleation (n = 4), total pancreatectomy (n = 3), Whipple procedure (n = 4), and distal pancreatectomy (n = 27). The median size of the resected tumors was 2.8 cm (range 0.6-11.0 cm). Recurrent disease developed in the residual pancreas in 7 (20%) of 35 at-risk patients a median of 7.8 years after the first operation, and distant metastases occurred in 5 (14 %) of 36 surgically treated patients without distant metastasis (2 patients had distant metastases when surgery on the primary tumor was performed) at a median of 2.7 years following surgery. At last follow-up, 16 (29%) of 55 patients with PETs had died, 12 (22%) were alive with disease, 26 (47%) were alive without evidence of disease, and 1 (2%) was lost to follow-up. The median OS was 19.5 years (range 13-26 years) and was significantly longer for patients who had functioning PETs versus those with nonfunctioning tumors (P = 0.0007), for patients who underwent surgical resection of their PETs versus those who did not (P = 0.0043), and for patients with localized versus metastatic PETs at the time of diagnosis (P < 0.0001). Multivariate analysis revealed that younger age, hormonal function, and PET resection were independently associated with longer OS.

CONCLUSIONS

Our data suggest that early diagnosis and surgical excision of MEN1-related PETs improves survival. However, translating these data into a surveillance strategy for the early detection of PETs is complex owing to the potential morbidity of pancreatic resection and the risk of long-term insulin dependence.

Pancreatectomy in multiple endocrine neoplasia type 1-related gastrinomas and pancreatic endocrine neoplasias

OBJECTIVE

The aim of this study was to evaluate the results of pancreatic resection in pancreatic endocrine neoplasias (PENs) in patients affected by multiple endocrine neoplasia type 1 (MEN1) syndrome.

BACKGROUND

Since these tumors often show an indolent course, the role of diagnostic procedures and type of surgical approach are controversial. Experience with new diagnostic approaches and more aggressive surgery is still limited.

METHODS

Sixteen MEN1 patients were referred to our Surgical Unit (1992-2003) and were operated on for the indications of hypergastrinism, hypoglycemia, and/or pancreatic endocrine neoplasias larger than 1 cm. Zollinger-Ellison syndrome (ZES) was present in 13 patients, 2 of whom experienced a recurrence after previous surgery. Preoperative tumor localization was carried out using ultrasonography (US), computed tomography (CT), endoscopic ultrasonography (EUS), somatostatin receptor scintigraphy (SSRS), or selective arterial secretin injection (SASI). Rapid intraoperative gastrin measurement (IGM) was carried out in 8 patients, and 1 patient also underwent an intraoperative secretin provocative test.

RESULTS

Either pancreatoduodenectomy (PD) or total pancreatectomy (TP) or distal pancreatectomy was performed. There was no postoperative mortality; 37% complications included pancreatic (27%) and biliary (6%) fistulas, abdominal collection (6%), and acute pancreatitis (6%). EUS and SSRS were the most sensitive preoperative imaging techniques. At follow-up, 10 of 13 hypergastrinemic patients (77%) are currently eugastrinemic with negative secretin provocative test, while 3 are showing a recurrence of the disease. All patients affected by insulinoma were cured.

CONCLUSIONS

MEN1 tumors should be considered surgically curable diseases. IGM may be of value in the assessment of surgical cure. Our experience suggests that PD is superior to less radical surgical approaches in providing cure with limited morbidity in MEN1 gastrinomas and pancreatic neoplasias.

Epidemiology data on 108 MEN 1 patients from the GTE with isolated nonfunctioning tumors of the pancreas

OBJECTIVE

To analyze the penetrance and clinical course of isolated nonfunctioning tumors of the pancreas (NFTP) in MEN 1 patients, and to propose a strategy for managing them.

SUMMARY BACKGROUND DATA

Pancreaticoduodenal tumors develop in a majority of MEN 1 patients and are a major cause of death. The natural history of NFTP is poorly defined, and no clear-cut guidelines have been widely accepted regarding treatment.

METHODS

Data on 108 patients with isolated NFTP among 579 MEN 1 patients from the French Endocrine Tumor Study Group (GTE) were analyzed. Survival rates were calculated using the Kaplan-Meier method.

RESULTS

The penetrance of NFTP was 34% at age 50, making it the most frequent pancreaticoduodenal tumor in MEN 1 patients. Forty-three patients (40%) underwent surgery, 32 of them curatively. No patient died because of surgery. Average life expectancy for patients with NFTP was shorter than that for MEN 1 patients who did not have pancreaticoduodenal tumors. Thirteen patients died during follow-up, 10 due to NFTP. Tumor size was correlated with the risks of metastasis and death. These risks were low for patients with tumors<or=20 mm.

CONCLUSIONS

NFTP are currently the most common tumors of the pancreaticoduodenal region in patients with MEN 1. Prevention of tumor spread by surgery should be balanced with potential operative mortality and morbidity. We do not recommend routine surgery for NFTP<or=20 mm.

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.

Prophylaktische Chirurgie des Pankreas

The goal of prophylactic surgery is to prevent malignant growth in patients with hereditary tumor predisposition. The pancreas presents as particularly challenging, due to the difficulty of operation and comparatively high risk of morbidity and even mortality. In addition, partial operative procedures and, more significantly, total resection lead to exocrine pancreas insufficiency and secondary diabetes, with grave consequences for the patient. Hereditary tumor predisposition syndromes that can result in pancreaticoduodenal endocrine tumors (PET) include multiple endocrine neoplasia type 1 syndrome and von Hippel-Lindau syndrome. As penetrance is maximally 70-80% and the 10-year survival rate over 80%, prophylactic pancreatic resection without evidence of a tumor is not indicated. However, prophylactic extension of a resection would be advised, should a PET be diagnosed. Patients predisposed to developing ductal pancreatic carcinoma (PC) are at risk of familial pancreatic cancer syndrome (FPC), hereditary pancreatitis, and other hereditary tumor predisposition syndromes such as Peutz-Jeghers syndrome and familial atypical multiple mole-melanoma syndrome. As the gene defect responsible for FPC has yet to be identified and the penetrance of PC in the other tumor predisposition syndromes is low or unknown, a prophylactic pancreatectomy based on today's knowledge is not indicated. Prophylactic extension of the resection is advisable should PC or high-grade PanIN lesions be diagnosed, as these patients often present with multifocal dysplasia and even carcinoma.

Laparoscopic enucleation of a nonfunctioning neuroendocrine tumor at the head of the pancreas

OBJECTIVE

Laparoscopy is a safe, feasible technique for benign pancreatic pathologies and has been increasingly reported for neuroendocrine tumors located at the body and tail of the pancreas. We report a case of successful enucleation of a nonfunctioning neuroendocrine tumor located at the head of the pancreas, in a patient with multiple endocrine neoplasia type I.

METHODS

A 5-cm nonfunctioning neuroendocrine tumor at the pancreatic head was identified by computerized tomography scan. Laparoscopic ultrasound did not reveal additional tumors on any other part of the pancreas.

RESULTS

Enucleation was successfully performed for this solitary tumor because of its favorable position. Histology revealed an islet cell tumor. No postoperative complications occurred and recovery was rapid.

CONCLUSION

Laparoscopic enucleation of neuroendocrine tumor at the pancreatic head is safe and feasible for select patients.

Outcome of duodenopancreatic resections in patients with multiple endocrine neoplasia type 1

OBJECTIVE

To evaluate the outcome of an aggressive surgical approach for duodenopancreatic neuroendocrine tumors (PETs) associated with multiple endocrine neoplasia type 1 (MEN1).

SUMMARY BACKGROUND DATA

The management of PETs is still controversial in the setting of the autosomal dominant inherited MEN1 syndrome.

METHODS

MEN1 patients that had either biochemical evidence of functioning PETs or visualized nonfunctioning PETs larger than 1 cm in size on imaging were operated. Since 1997, patients were followed annually by biochemical testing and imaging studies.

RESULTS

Twenty-six genetically confirmed MEN1 patients underwent duodenopancreatic resection for functioning (n = 17) or nonfunctioning (n = 9) PETs. Ten (38%) patients had malignant PETs as characterized by the presence of lymph node (10 patients) and/or distant metastases (2 patients). The surgical approach was selected based on the type, location, and size of PETs. Four Zollinger-Ellison syndrome (ZES) patients required pylorus preserving pancreaticoduodenectomy (PPPD) as initial or redo procedure, 20 patients underwent other duodenopancreatic resections, and 2 patients had simple enucleations of PETs. After median 83 months (range, 5-241 months), 24 patients were alive and 2 patients died of an unrelated cause. All patients with insulinoma or vipoma and 7 of 11 patients with ZES were biochemically cured, including the ZES patients who underwent PPPD. However, 19 of 26 (73%) patients developed new small PETs (<1 cm) in the pancreatic remnant, but no patient had yet detectable metastases on imaging.

CONCLUSIONS

Early and aggressive surgery of PETs in MEN1 patients prevents the development of liver metastases, which are the most life-threatening determinant. PPPD might be the procedure of choice for MEN1-ZES, which has to be proven in large scale studies.

Pancreatic tumours as part of the MEN-1 syndrome

Pancreaticoduodenal tumours (PETs) occur in a majority of MEN-1 patients, and have appeared as a major cause of disease-related death. Previous discussions about treatment have mainly dealt with management of various functioning tumours and clinical syndromes of hormone excess. However, hormonal syndromes often occur late with MEN-1 pancreatic tumours, and when developed indicate presence of metastases in up to 50% of the patients. Prospective screening is therefore recommended in MEN-1 with biochemical markers and endoscopic ultrasound for early detection of PETs, and early surgery before metastases have developed. Surgery is recommended in patients with or without hormonal syndromes in absence of disseminated liver metastases. The suggested operation includes enucleation of tumours in the head of the pancreas, excision of duodenal gastrinomas together with clearance of lymph node metastases, and distal 80% subtotal pancreatic resection as prophylaxis against tumour recurrence. This strategy with early and aggressive surgery is believed to reduce the risks for malignant progression.

[Surgical treatment of gastric, enteric, and pancreatic endocrine tumors Part 1. Treatment of primary endocrine tumors]

Endocrine tumors (ET) of the digestive tract (formerly called neuroendocrine tumors) are rare. They are classified into two principal types: gastrointestinal ET's (formerly called carcinoid tumors) which are the most common, and pancreaticoduodenal ET's. Functioning ET's secrete polypeptide hormones which cause characteristic hormonal syndromes. The management of ET is multidisciplinary. Poorly-differentiated ET's have a poor prognosis and are treated by chemotherapy. Surgical excision is the only curative treatment of well-differentiated ET's. The surgical goals are to: 1. prolong survival by resecting the primary tumor and any nodal or hepatic metastases, 2. control the symptoms related to hormonal secretion, 3. prevent or treat local complications. The most common sites of gastrointestinal ET's ( carcinoids) are the appendix and the rectum; these are often small (<1 cm), benign, and discovered fortuitously at the time of appendectomy or colonoscopic removal. Ileal ET's, even if small, are malignant, frequently multiple, and complicated in 30-50% of cases by bowel obstruction, mesenteric invasion, or bleeding. The carcinoid syndrome (consisting of abdominal pain, flushing, diarrhea, hypertension, bronchospasm, and right sided cardiac vegetations) is caused by the hypersecretion of serotonin into the systemic circulation; it occurs in 10% of cases and is usually associated with hepatic metastases. More than half of the cases of pancreatic ET are non-functional. They are usually malignant and of advanced stage at diagnosis presenting as a palpable or obstructing mass or as liver metastases. Insulinoma and gastrinoma (cause of the Zollinger-Ellison syndrome) are the most common functional ET's. 80% are sporadic; in these cases, tumor size, location, and malignant potential determine the type of resection which may vary from a simple enucleation to a formal pancreatectomy. In 10-20% of cases, pancreaticoduodenal ET presents in the setting of multiple endocrine neoplasia (NEM type I), an autosomal-dominant genetic disease with multifocal endocrine involvement of the pituitary, parathyroid, pancreas, and adrenal glands. For insulinoma with NEM-I, enucleation of lesions in the pancreatic head plus a caudal pancreatectomy is the most appropriate procedure. For gastrinoma with NEM-I, the benefit of surgical resection for tumors less than 2-3 cm in size is not clear. The lesions are frequently small, multiple, and widespread and recurrence is frequent after excision. The long-term prognosis is nevertheless fairly good. But the eventual development of liver metastases which are the most common cause of mortality still argues for an aggressive surgical approach in the early stages of the disease.

[Zollinger-Ellison syndrome]

The preoperative localization of gastrinomas often fails despite all modern imaging methods. Therefore, after biochemical confirmation of the diagnosis and exclusion of diffuse metastases, a meticulous surgical exploration including intraoperative ultrasound (IOUS) and duodenal exploration after duodenotomy should be performed. The experienced surgeon will be able to identify more than 90% of the primary tumors. Depending on the localization, excision of the tumor in the duodenal wall or enucleation from the pancreatic head should be performed. If the tumor is localized in the tail of the pancreas, distal pancreatectomy is the treatment of choice. Complete resection of the tumor is the only curative approach for the patients. For MEN-1 gastrinomas a spleen-preserving distal pancreatectomy with enucleation of tumors of the pancreatic head and duodenotomy with excision of duodenal gastrinomas should be performed. If the source of gastrin secretion can be regionalized to the pancreatic head by a preoperative SASI angiography, a pylorus-preserving partial pancreaticoduodenectomy might be the treatment of choice.

Endocrine pancreatic tumors

Neuroendocrine tumors of the pancreas are rare neoplasms that may arise sporadically or in association with a hereditary endocrine neoplasia syndrome. Effective management requires directed biochemical testing, careful choice of preoperative imaging tests, and complete pancreatic exploration by an experienced endocrine surgeon utilizing intraoperative ultrasound. Pancreatic endocrine tumors arising in the familial setting present unique diagnostic and therapeutic dilemmas.

Multiple endocrine neoplasia type 1

Multiple endocrine neoplasia-1 (MEN-1) is an autosomal dominant inherited syndrome that occurs due to inactivating mutations of the MEN1 gene locus, coding for a tumor-suppressor protein, menin. The components of MEN-1 are hyperparathyroidism due to multiple parathyroid adenomas, pancreatic neuroendocrine tumors, and pituitary adenomas, in addition to some less common neoplastic manifestations. Care of people with MEN-1 requires knowledge of the problems that may arise, and the best approaches to detect and care for the manifestations of this incurable, but manageable, disease.