Surgical management of patients with insulinomas: Result of 292 cases in a single institution

Endoscopic management of pancreatic fistula after enucleation of pancreatic tumors

INTRODUCTION

Pancreatic fistula (PF) are frequent after pancreatic surgical resection, and particularly after enucleation. Endoscopic treatment might be proposed for postoperative PF, but has never been evaluated after pancreatic enucleation.

PATIENTS AND METHODS

From January 2000 to June 2012, 161 patients underwent pancreatic enucleation in our center. In case of PF in the postoperative period, conservative management (somatostatin analogs combined with enteral or parenteral nutrition and drainage) was proposed. If PF persisted after 20 days (output >50 cc/d), endoscopic treatment (pancreatic sphincterotomy and stent placement if evidence of main duct leakage) was proposed. Primary outcome was the delay of PF closure after endoscopic treatment.

RESULTS

Ninety-one patients (56 %) developed postoperative PF. PF closed within 3 weeks with conservative management in 78 (86 %) patients. Endoscopic treatment was required in 7 (8 %) patients. Daily PF output was 240 (50-300) mL. Pancreatic sphincterotomy was performed in all patients. A pancreatic stent was inserted in 4 of 5 patients with main pancreatic duct leakage. One patient presented a stent migration requiring a second procedure. No complication of endoscopic treatment was reported. The closure of PF was obtained in all cases, after 13 (3-24) days. Pancreatic stents were removed after 2, 5, 5, and 8 months, respectively. Median postoperative follow-up was 46 (21-70) months. At study endpoint, two patients had small asymptomatic pancreatic collections, four had mild dilatation of main pancreatic duct upstream pancreatic duct leakage, and none developed exocrine pancreatic insufficiency, diabetes, or recurrence of pancreatic tumor.

CONCLUSIONS

PF occurs in half patients after enucleation. Endoscopic treatment combining pancreatic sphincterotomy and stenting is safe and effective if conservative treatment fails, avoiding a complementary pancreatic resection.

Chromogranin A is a reliable serum diagnostic biomarker for pancreatic neuroendocrine tumors but not for insulinomas

BACKGROUND

Pancreatic neuroendocrine tumors (PNETs) are a group of rare tumors. Chromogranin A (CgA) was considered as the most practical and useful serum tumor marker in PNET patients. But peripheral blood levels of CgA are not routinely tested in Chinese patients with PNETs. This study was to assess the diagnostic value of CgA in Chinese patients with PNETs especially in patients with insulinomas.

METHODS

Eighty-nine patients with PNETs including 57 insulinomas and 32 non-insulinoma PNETs as well as 86 healthy participants were enrolled in this study between September 2003 and June 2013. Serum levels of CgA were measured by ELISA method. Expression of CgA protein was detected in 26 PNET tissues including 14 insulinomas by immunohistochemical staining.

RESULTS

Serum levels of CgA in 89 PNET patients were significantly higher than that in healthy controls (P = 7.2 × 10-9). Serum levels of CgA in 57 patients with insulinomas (median 64.8 ng/ml, range 25-164) were slightly higher than the levels in healthy controls (median 53.4 ng/ml, range 39-94) but much lower than the levels in 32 patients with non-insulinoma PNETs (median 193 ng/ml, range 27-9021), P = 0.001. The serum CgA levels were reduced in 16 of 17 patients with insulinomas after tumor resection. ROC curve showed that CgA values at 60 ng/ml distinguished patients with insulinomas from healthy controls but its sensitivity and specificity were 66.7% and 73.3%, respectively. In contrast, CgA values at 74 ng/ml distinguished patients with non-insulinoma PNETs from healthy controls, and the sensitivity and specificity were 65.6% and 91.9%, respectively. Except for two insulinomas with negative staining of CgA, 12 insulinoma tissues showed positive staining of CgA.

CONCLUSION

CgA is a reliable serum diagnostic biomarker for PNETs but not for insulinomas.

[Minimally invasive pancreatic tumor surgery : oncological safety and surgical feasibility]

INTRODUCTION AND PURPOSE

Despite being technically challenging, minimally-invasive pancreatic surgery is increasingly being used to treat pancreatic diseases. Therefore, the evaluation of its oncological safety and its advantages arebecoming increasingly more important. This review focuses on these questions based on the currently available literature.

MATERIAL AND METHODS

The technically less demanding laparoscopic distal pancreatectomy has been evaluated in numerous meta-analyses. Minimally invasive pancreaticoduodenectomy has only been reported from a few centers worldwide.

RESULTS AND CONCLUSION

Minimally invasive pancreatic surgery, in particular laparoscopic distal pancreatectomy, is increasingly being used to treat pancreatic tumors. The advantages of laparoscopy, such as less intraoperative blood loss, reduced postoperative pain and a shorter length of stay have all been demonstrated in large trials. However, a sufficient oncological treatment was only assessed via indirect surrogate parameters, such as the number of lymph nodes obtained and R0 resection rates; therefore, larger prospective trials are needed to prove adequate oncological treatment. To date, minimally invasive techniques should only be employed in trials on treatment of pancreatic malignancies.

Laparoscopic spleen-preserving distal pancreatectomy for insulinoma: experience of a single center

BACKGROUND

Laparoscopic spleen-preserving distal pancreatectomy is gaining acceptance for the treatment of insulinomas of the pancreatic body and tail. The aim of this report is to evaluate the feasibility, safety and outcomes of this procedure in a retrospective series.

METHODS

From May 2004 to November 2013, 9 patients underwent laparoscopic spleen-preserving distal pancreatectomy for benign insulinomas in our department. Tumors were single and sporadic in eight patients, while the remaining patient had insulinomas in the setting of multiple endocrine neoplasia type 1. Tumors were located by preoperative imaging in all cases. Laparoscopic ultrasound was always performed to guide the surgical procedure.

RESULTS

All the operations were carried out laparoscopically with a mean operative time of 110 min (range 90-210 min) and a mean blood loss of 50 ml (range 30-120 ml). One patient (11.1%) died on the 22nd post-operative day for massive intra-abdominal bleeding associated with pancreatitis of the stump. Two patients (22.2%) developed pancreatic fistula that healed conservatively. Mean postoperative hospital stay was 7.1 days (range 5-18 days). All alive patients were free from recurrence after a mean follow-up of 45 months (range 11-72 months).

CONCLUSION

Laparoscopic spleen-preserving distal pancreatectomy is safe and feasible for the management of benign insulinomas. Definition of the tumor with preoperative imaging and laparoscopic ultrasound is essential to achieve high cure rate with minimal conversion.

[Malignant insulinoma: recommendations for workup and treatment]

Insulinoma are malignant in 4 to 14 % of cases. Their rarity and the sparse data available in the literature have limited publication of specific guidelines for their management. The following review aim to provide up-to-date recommendations on initial evaluation including pathologic grading, measures to control hypoglycemia, antitumor strategies and long term follow-up. Will be discussed in detail respective indications of surgery, diazoxide, somatostatin analogs, everolimus, sunitinib, liver directed treatments including arterial embolization, chemotherapy and radiometabolic therapy. A Medline search using terms "insulinoma", "neuroendocrine pancreatic tumors", "islet cell carcinoma", "malignant insulinoma" was performed limiting the selection to English language articles and adult age cases, along with cross referencing.

Laparoscopic versus open pancreas resection for pancreatic neuroendocrine tumours: a systematic review and meta-analysis

BACKGROUND

Over the last decade laparoscopic pancreatic surgery (LPS) has emerged as an alternative to open pancreatic surgery (OPS) in selected patients with neuroendocrine tumours (NET) of the pancreas (PNET). Evidence on the safety and efficacy of LPS is available from non-comparative studies.

OBJECTIVES

This study was designed as a meta-analysis of studies which allow a comparison of LPS and OPS for resection of PNET.

METHODS

Studies conducted from 1994 to 2012 and reporting on LPS and OPS were reviewed. Studies considered were required to report on outcomes in more than 10 patients on at least one of the following: operative time; hospital length of stay (LoS); intraoperative blood loss; postoperative morbidity; pancreatic fistula rates, and mortality. Outcomes were compared using weighted mean differences and odds ratios.

RESULTS

Eleven studies were included. These referred to 906 patients with PNET, of whom 22% underwent LPS and 78% underwent OPS. Laparoscopic pancreatic surgery was associated with a lower overall complication rate (38% in LPS versus 46% in OPS; P < 0.001). Blood loss and LoS were lower in LPS by 67 ml (P < 0.001) and 5 days (P < 0.001), respectively. There were no differences in rates of pancreatic fistula, operative time or mortality.

CONCLUSIONS

The nature of this meta-analysis is limited; nevertheless LPS for PNET appears to be safe and is associated with a reduced complication rate and shorter LoS than OPS.

Endogenous hyperinsulinemic hypoglycemia syndrome: surgical treatment

BACKGROUND

The endogenous hyperinsulinemic hypoglicemia syndrome (EHHS) can be caused by an insulinoma, or less frequently, by nesidioblastosis in the pediatric population, also known as non insulinoma pancreatic hypoglycemic syndrome (NIPHS) in adults. The aim of this paper is to show the strategy for the surgical treatment of ehhs.

MATERIAL AND METHODS

A total of 19 patients with a final diagnosis of insulinoma or NIPHS who were treated surgically from january 2007 until june 2012 were included. We describe the clinical presentation and preoperative work-up. Emphasis is placed on the surgical technique, complications and long-term follow-up.

RESULTS

All patients had a positive fasting plasma glucose test. Preoperative localization of the lesions was possible in 89.4% of cases. The most frequent surgery was distal pancreatectomy with spleen preservation (9 cases). Three patients with insulinoma presented with synchronous metastases, which were treated with simultaneous surgery. There was no perioperative mortality and morbidity was 52.6%. Histological analysis revealed that 13 patients (68.4%) had benign insulinoma, 3 malignant insulinoma with liver metastases and 3 with a final diagnosis of SHPNI. Median follow-up was 20 months. All patients diagnosed with benign insulinoma or NIPHS had symptom resolution.

CONCLUSION

The surgical treatment of EHHS achieves excellent long-term results in the control of hypoglucemic symptoms.

Comparison of two low-dose calcium infusion schedules for localization of insulinomas by selective pancreatic arterial injection with hepatic venous sampling for insulin

OBJECTIVE

Localization of small insulinomas may be difficult. Selective pancreatic arterial injection of calcium with hepatic venous insulin measurement (SACST) has been used for this purpose, but can rarely cause hypoglycaemia. Two low-dose concentrations of calcium, 0·25 and 0·1 of the usual concentration used for the test, have been compared for sensitivity of localization and safety.

DESIGN

Selective pancreatic arterial injection of calcium with hepatic venous insulin measurement was performed at calcium concentrations of 0·0025 (Protocol A) and 0·00625 (Protocol B) mEq calcium per kg. The standard concentration is 0·025 mEq/kg.

PATIENTS

Twenty one successive patients with biochemical evidence of insulinoma were studied.

RESULTS

Using surgical localization as the gold standard, Protocol A had a sensitivity of 91% and Protocol B 75% for correct localization. The false-positive localization rate was 16%. No hypoglycaemia was observed. These results compare favourably with published data using the standard calcium concentration. Selective pancreatic arterial injection of calcium with hepatic venous insulin measurement was superior to localization by noninvasive imaging; in seven cases, SACST was correct when conventional imaging was negative (five) or false positive (two).

CONCLUSION

Low concentrations of calcium are effective and safe when performing SACST for localization of insulinoma.

Laparoscopic pancreatic resections

PURPOSE

Pancreatic surgery is technically complex and requires considerable expertise. Laparoscopic pancreatic surgery adds the need for considerable experience with advanced laparoscopic techniques. Despite the technical difficulties, an increasing number of centers propagate the use of laparoscopy in pancreatic surgery over the last decade.

METHODS

In this review, we provide an overview of the literature regarding the advantages and disadvantages of laparoscopic pancreatic surgery. Larger prospective randomized studies have emerged in the subset of laparoscopic or retroperitoneoscopic surgery for acute pancreatitis, considerable single center experience has been reported for laparoscopic pancreatic tail resection, and laparoscopic pancreatic head resection, however, is still restricted to a few experienced centers worldwide.

RESULTS AND CONCLUSIONS

Laparoscopic pancreatic surgery is becoming more and more established, in particular for the treatment of benign and premalignant lesions of the pancreatic body and tail. It has been shown to decrease postoperative pain, narcotic use, and length of hospital stay in larger single center experience. However, prospective trials are needed in laparoscopic resective pancreatic surgery to evaluate its advantages, safety, and efficacy in the treatment of pancreatic neoplasms and in particular in malignant pancreatic tumors.

Is laparoscopic approach for pancreatic insulinomas safe? Results of a systematic review and meta-analysis

BACKGROUND

No consensus exists as to whether laparoscopic treatment for pancreatic insulinomas (PIs) is safe and feasible. The aim of this meta-analysis was to assess the feasibility, safety, and potential benefits of laparoscopic approach (LA) for PIs. The abovementioned approach is also compared with open surgery.

METHODS

A systematic literature search (MEDLINE, EMBASE, Cochrane Library, Science Citation Index, and Ovid journals) was performed to identify relevant articles. Articles that compare the use of LA and open approach to treat PI published on or before April 30, 2013, were included in the meta-analysis. The evaluated end points were operative outcomes, postoperative recovery, and postoperative complications.

RESULTS

Seven observational clinical studies that recruited a total of 452 patients were included. The rates of conversion from LA to open surgery ranged from 0%-41.3%. The meta-analysis revealed that LA for PIs is associated with reduced length of hospital stay (weighted mean difference, -5.64; 95% confidence interval [CI], -7.11 to -4.16; P < 0.00001). No significant difference was observed between LA and open surgery in terms of operation time (weighted mean difference, 2.57; 95% CI, -10.91 to 16.05; P = 0.71), postoperative mortality, overall morbidity (odds ratio [OR], 0.64; 95% CI, 0.35-1.17; P = 0.14], incidence of pancreatic fistula (OR, 0.86; 95% CI, 0.51-1.44; P = 0.56), and recurrence of hyperglycemia (OR, 1.81; 95% CI, 0.41-7.95; P = 0.43).

CONCLUSIONS

Laparoscopic treatment for PIs is a safe and feasible approach associated with reduction in length of hospital stay and comparable rates of postoperative complications in relation with open surgery.

Risk factors for the occurrence of insulinoma: a case-control study

BACKGROUND

The etiology of insulinoma is poorly understood. Few studies investigated the possible roles of environmental factors and lifestyle in the pathogenesis of insulinoma. The aim of this study is to identify risk factors associated with occurrence of insulinoma in the Chinese population.

METHODS

This study consisted of 196 patients with insulinoma and 233 controls. Demographic information of the patients and controls and risk factors of the disease were analyzed. Univariate and unconditional multivariable logistic regression analyses were made to estimate odds ratios (ORs) and possible risk factors.

RESULTS

Approximately 68.88% (135/196) of the patients were from rural areas in contrast to 10.30% (24/233) of the controls (P<0.0001). This difference was confirmed by the multivariate analysis (OR=4.950; 95% CI: 2.928-8.370). Family history of pancreatic endocrine tumor (OR=16.754; 95% CI: 2.125-132.057) and other cancers (OR=2.360; 95% CI: 1.052-5.291) was also related to a high-risk population of insulinoma.

CONCLUSION

Rural residents or people who have a family history of pancreatic endocrine tumor and other cancers are a high-risk population of insulinoma.

Pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (pancreatic NETs) are rare, low- to intermediate-grade neoplasms thought to arise from the pancreatic islets. Recent advances in pathology and our understanding of the biological behavior of this group of tumors has resulted in changes in their nomenclature and how we treat them. This review puts into perspective our current understanding of pancreatic NETs in terms of their incidence, pathology, and management.

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.

Pancreatic neuroendocrine tumors: biology, diagnosis,and treatment

Pancreatic neuroendocrine tumors (PNETs), a group of endocrine tumors arising in the pancreas, are among the most common neuroendocrine tumors. The genetic causes of familial and sporadic PNETs are somewhat understood, but their molecular pathogenesis remains unknown. Most PNETs are indolent but have malignant potential. The biological behavior of an individual PNET is unpredictable; higher tumor grade, lymph node and liver metastasis, and larger tumor size generally indicate a less favorable prognosis. Endocrine testing, imaging, and histological evidence are necessary to accurately diagnose PNETs. A 4-pronged aggressive treatment approach consisting of surgery, locoregional therapy, systemic therapy, and complication control has become popular in academic centers around the world. The optimal application of the multiple systemic therapeutic modalities is under development; efficacy, safety, availability, and cost should be considered when treating a specific patient. The clinical presentation, diagnosis, and treatment of specific types of PNETs and familial PNET syndromes, including the novel Mahvash disease, are summarized.

Surgical treatment of sporadic pancreatic neuroendocrine tumors: a state of the art review

Pancreatic neuroendocrine tumors (PNETs) are rare neoplasms. They are clinically diverse and divided into functioning and nonfunctioning disease, depending on their ability to produce symptoms due to hormone production. Surgical resection is the only curative treatment and remains the cornerstone therapy for this patient group, even in patients with advanced disease. Over the last decade there has been a noticeable trend towards more aggressive surgery as well as more minimally invasive surgery in patients with PNETs. This has resulted in improved long-term survival in patients with locally advanced and metastatic disease treated aggressively, as well as shorter hospital stays and comparable long-term outcomes in patients with limited disease treated minimally invasively. There are still controversies related to issues of surgical treatment of PNETs, such as to what extent enucleation, lymph node sampling, and vascular reconstruction are beneficial for the oncologic outcome. Histopathologic tumor classification is of high clinical importance for treatment planning and prognostic evaluation of patients with PNETs. A constant challenge, which relates to the treatment of PNETs, is the lack of an internationally accepted histopathological classification system. This paper reviews current issues on the surgical treatment of sporadic PNETs with specific focus on surgical approaches and tumor classification.

Surgery for GEP-NETs

Surgery is the only treatment that may cure the patient with gastroentero-pancreatic (GEP) neuroendocrine tumours (NET) and neuroendocrine carcinomas (NEC) and should always be considered as first line treatment if R0/R1 resection can be achieved. The surgical and interventional procedures for GEP-NET are accordingly described below. Life-long follow-up should be performed in almost all patients at a specialized NET center.

Risk factors for postoperative pancreatic fistulization subsequent to enucleation

INTRODUCTION

Pancreatectomies increase the risk of postoperative pancreatic fistula (POPF) and pancreatic insufficiency. Pancreatic enucleation preserves pancreatic parenchyma, lowers the risk of pancreatic insufficiency, but may induce specific complications (tumor recurrence or pancreatic fistulization). The aim of this study was to determine the risk factors for POPF following a pancreatic enucleation.

METHODS

A retrospective analysis was designed based on data from patients who underwent pancreatic enucleation in five university hospitals (1998-2008). The presence of a pancreatic fistula was determined according to the criteria of the International Study Group of Pancreatic Fistula (Bassi et al. Surgery 138:8-13, 2005).

RESULTS

Fifty-two patients (mean age 52 years) were included. Histological analysis revealed 35 endocrine tumors (68.6 %), 6 mucinous and 2 serous cyst adenomas, 2 metastases of renal cancer, and 8 benign tumors. Nineteen patients (36.5%) suffered postoperative complications including 14 POPF (27 %). Median postoperative hospital stay was 12.9 days; 9.1 days without POPF versus 29 days with POPF (p < 0.05). Size of the tumor, its location, histological differentiation, and use of somatostatin analogs were not predictors for POPF. We defined the cutoff for POPF at a distance of 2 mm from the main pancreatic duct based on 60% risk (≤2 mm) versus 19 % (>2 mm) of POPF (p < 0.01). With a mean follow-up of 30.8 months, one patient experienced recurrence of the tumor. No patients exhibited a new onset of diabetes or pancreatic insufficiency.

CONCLUSION

Enucleation for resection of pancreatic tumors located at less than or equal to two 2 mm from the main pancreatic duct is a risk factor for POPF. Enucleation is a safe and effective treatment for benign or borderline pancreatic tumors.

Tumor enucleation with preoperative endoscopic transpapillary stenting for pediatric insulinoma

The 13-year-old boy underwent tumor enucleation for pancreatic head insulinoma close to the pancreatic main duct after a preoperative endoscopic pancreatic stent placed by endoscopic retrograde cholangiopancreatography. The tumor was safely excised by identifying the indwelled pancreatic stent during the surgical procedure without pancreatic duct injury or postoperative complications.

Activated mTOR/P70S6K signaling pathway is involved in insulinoma tumorigenesis

BACKGROUND

Insulinoma was a rare tumor and its pathogenesis was poorly understood. There had no study that focused on the role of mTOR signaling pathway in insulinoma tumorigenesis.

MATERIALS AND METHODS

Expression of p-mTOR and its downstream p-P70S6K in insulinoma and normal pancreatic tissue was evaluated by immunohistochemical staining and Western blotting. In vitro study, an insulinoma cell line (INS-1) was treated with inhibitors of mTOR (rapamycin) or dual PI3K/mTOR inhibitor (NVP-BEZ235), RT-PCR, and Western blotting were applied to evaluate their influence on the expression of mTOR and P70S6K. Cell proliferation was evaluated by MTT test, cell cycle and apoptosis were analyzed by flow cytometry, insulin secretion level was evaluated by GSIS method.

RESULTS

Positive expression of p-mTOR and p-P70S6K was much higher in insulinoma tumor specimens than the normal pancreatic islet (P < 0.05). mTOR inhibitors can induce decreased expression of mTOR and P70S6K, which resulting in inhibiting INS-1 cell proliferation, insulin secretion and inducing apoptosis. NVP-BEZ235 had better influence on inhibiting the cell proliferation and inducing apoptosis than rapamycin.

CONCLUSION

mTOR/P70S6K signaling pathway is involved in tumorigenesis of insulinoma, NVP-BEZ235 and rapamycin offer a promising role as novel drugs in treatment of insulinoma.

The minimally invasive approach to surgical management of pancreatic diseases

Laparoscopic pancreas surgery has undergone rapid development over the past decade. Although acceptability among traditional surgeons has been low, emerging specialty centers are reporting excellent outcomes for advanced and complex operations, such as pancreaticoduodenectomy. A note of caution is necessary: These outstanding results are from skilled surgeons, many of whom are pioneers in the field, who have overcome the learning curve over many years of innovation. As the procedures gain wider practice, outcomes need to be carefully watched because many of these procedures are extremely demanding technically. Although many have suggested that controlled, randomized studies comparing laparoscopic pancreatic resections with open resections are necessary to establish the efficacy of laparoscopic procedure, the cumulative data on the safety and efficacy of the laparoscopic procedure argues against such an approach. The logistic difficulties of conducting such studies will be considerable given patient preferences, the need for multicenter studies, and the rapid adoption of the laparoscopic procedure among experienced pancreatic surgeons. A more reasonable approach to truly evaluate the safety of these procedures is the establishment of a national registry that can measure progress of the field and record outcomes in the wider, nonspecialty community. Hepatobiliary training programs should also establish a minimal standard of training for many of the advanced procedures, such as the pancreaticoduodenectomy, so that the benefit of laparoscopic surgery can be made available outside of just a few specialty centers.

Clinical features of insulinoma in patients with multiple endocrine neoplasia type 1: analysis of the database of the MEN Consortium of Japan

More than 50% of patients with multiple endocrine neoplasia type 1 (MEN1) develop gastroenteropancreatic neuroendocrine tumors (GEPNETs), and insulinoma is the second most common functioning GEPNET. Compared to other functioning and nonfunctioning GEPNETs in MEN1, insulinoma is considered to develop at a younger age. To clarify the clinical features of insulinoma developed in Japanese patients with MEN1, a recently constructed database of Japanese MEN1 patients was analyzed. Among 560 registered cases, insulinoma was seen in 69 patients and information on age at diagnosis was available for 54 patients. Tumors predominantly occurred in the body and tail of the pancreas. The mean age at diagnosis of insulinoma (34.8 ± 16.7 yrs) was significantly younger than that of gastrinoma (50.6 ± 14.3 yrs) and nonfunctioning tumor (44.7 ± 13.3 yrs) in patients with MEN1. Patients diagnosed as having insulinoma during middle-age (30 - 49 yrs) tended to have a long period from appearance of hypoglycemic symptoms to diagnosis of the tumor. Of note, 13 patients (24%) were diagnosed as having insulinoma before 20 yrs of age. Such young onset was not seen in other GEPNETs. Since the development of GEPNETs during adolescence is quite rare, insulinoma diagnosed before 20 yrs strongly suggests the presence of MEN1 and warrants further investigation, including MEN1 genetic testing. Also, clinicians should be aware that insulinoma can often be missed in middle-aged patients.

New therapeutic options for metastatic malignant insulinomas

Insulinomas are the most common, functioning, pancreatic neuroendocrine tumours. The great majority (>90%) of insulinomas are nonmetastatic at presentation and can be surgically cured. The <10% patients with distant (liver-bone) metastases have a median survival of < 2 years. Everolimus and sunitinib have been recently introduced as targeted therapies for metastatic pancreatic neuroendocrine tumours. An additional advantage of everolimus in the treatment of patients with metastatic insulinomas is its capability to increase blood glucose levels. Peptide receptor radiotherapy using radiolabelled somatostatin analogues has also been shown to be successful in controlling tumour growth of metastatic pancreatic neuroendocrine tumours. In patients with metastatic insulinomas, this therapeutic modality was also effective in controlling hypoglycaemia, even in the presence of tumour regrowth. With the introduction of these new therapeutic modalities, the therapeutic arsenal for the 'tailor-made' approach of patients with metastatic insulinomas is further expanded.

Current surgical management of pancreatic endocrine tumor liver metastases

BACKGROUND

The management of metastatic disease in pancreatic endocrine tumors (PETs) demands a multidisciplinary approach and the cooperation of several medical specialties. The role of surgery is critical, even when a radical excision cannot always be achieved.

DATA SOURCES

A PubMed search of relevant articles published up to February 2011 was performed to identify current information about PET liver metastases regarding diagnosis and management, with an emphasis on surgery.

RESULTS

The early diagnosis of metastases and their accurate localization, most commonly in the liver, is very important. Surgical options include radical excision, and palliative excision to relieve symptoms in case of failure of medical treatment. The goal of the radical excision is to remove the primary tumor bulk and all liver metastases at the same time, but unfortunately it is not feasible in most cases. Palliative excisions include aggressive tumor debulking surgeries in well-differentiated carcinomas, trying to remove at least 90% of the tumor mass, combined with other additional destructive techniques such as hepatic artery embolization or chemoembolization to treat metastases or chemoembolization to relieve symptoms in cases of rapidly growing tumors. The combination of chemoembolization and systemic chemotherapy results in better response and survival rates. Other local destructive techniques include ethanol injection, cryotherapy and radiofrequency ablation.

CONCLUSION

It seems that the current management of PETs can achieve important improvements, even in advanced cases.