Insulinoma

Robotic versus laparoscopic surgery for sporadic benign insulinoma: Short- and long-term outcomes

BACKGROUND

Minimally invasive surgery is the optimal treatment for insulinoma. The present study aimed to compare short- and long-term outcomes of laparoscopic and robotic surgery for sporadic benign insulinoma.

METHODS

A retrospective analysis of patients who underwent laparoscopic or robotic surgery for insulinoma at our center between September 2007 and December 2019 was conducted. The demographic, perioperative and postoperative follow-up results were compared between the laparoscopic and robotic groups.

RESULTS

A total of 85 patients were enrolled, including 36 with laparoscopic approach and 49 with robotic approach. Enucleation was the preferred surgical procedure. Fifty-nine patients (69.4%) underwent enucleation; among them, 26 and 33 patients underwent laparoscopic and robotic surgery, respectively. Robotic enucleation had a lower conversion rate to laparotomy (0 vs. 19.2%, P = 0.013), shorter operative time (102.0 vs. 145.5 min, P = 0.008) and shorter postoperative hospital stay (6.0 vs. 8.5 d, P = 0.002) than laparoscopic enucleation. There were no differences between the groups in terms of intraoperative blood loss, the rates of postoperative pancreatic fistula and complications. After a median follow-up of 65 months, two patients in the laparoscopic group developed a functional recurrence and none of the patients in the robotic group had a recurrence.

CONCLUSIONS

Robotic enucleation can reduce the conversion rate to laparotomy and shorten operative time, which might lead to a reduction in postoperative hospital stay.

Genotype-histotype-phenotype correlations in hyperinsulinemic hypoglycemia

Hyperinsulinemic hypoglycemia (HH) of pancreatic origin includes congenital hyperinsulinism (CHI), insulinoma, insulinomatosis, and adult-onset non-insulinoma persistent hyperinsulinemic hypoglycemia syndrome (NI-PHHS). In this review, we describe the genotype-histotype-phenotype correlations in HH and their therapeutic implications. CHI can occur from birth or later on in life. Histologically, diffuse CHI shows diffuse beta cell hypertrophy with a few giant nuclei per islet of Langerhans, most frequently caused by loss-of-function mutations in ABCC8 or KCNJ11. Focal CHI is histologically characterized by focal adenomatous hyperplasia consisting of confluent hyperplastic islets, caused by a paternal ABCC8/KCNJ11 mutation combined with paternal uniparental disomy of 11p15. CHI in Beckwith-Wiedemann syndrome is caused by mosaic changes in the imprinting region 11p15.4-11p15.5, leading to segmental or diffuse overgrowth of endocrine tissue in the pancreas. Morphological mosaicism of pancreatic islets is characterized by occurence of hyperplastic (type 1) islets in one or a few lobules and small (type 2) islets in the entire pancreas. Other rare genetic causes of CHI show less characteristic or unspecific histology. HH with a predominant adult onset includes insulinomas, which are pancreatic insulin-producing endocrine neoplasms, in some cases with metastatic potential. Insulinomas occur sporadically or as part of multiple endocrine neoplasia type 1 due to MEN1 mutations. MAFA mutations may histologically lead to insulinomatosis with insulin-producing neuroendocrine microadenomas or neuroendocrine neoplasms. NI-PHHS is mainly seen in adults and shows slight histological changes in some patients, which have been defined as major and minor criteria. The genetic cause is unknown in most cases. The diagnosis of HH, as defined by genetic, histological, and phenotypic features, has important implications for patient management and outcome.

Approach to the Hypoglycemic Patient

Hypoglycemia is commonly encountered in the emergency department. Patients can present with a myriad of symptoms and its presentation can mimic other more serious diagnoses. Despite the relative ease of its management, clinicians often miss the diagnosis or mismanage it even when discovered. Glucose is an important energy source for the brain and failing to recognize hypoglycemia or mismanaging it can lead to permanent neurologic disability or death. Although it is important to replenish glucose in a rapid fashion, it is equally important to discover and manage the underlying etiology to prevent further episodes of hypoglycemia.

Mechanism and recent updates on insulin-related disorders

Insulin, a small protein with 51 amino acids synthesized by pancreatic β-cells, is crucial to sustain glucose homeostasis at biochemical and molecular levels. Numerous metabolic dysfunctions are related to insulin-mediated altered glucose homeostasis. One of the significant pathophysiological conditions linked to the insulin associated disorder is diabetes mellitus (DM) (type 1, type 2, and gestational). Insulin resistance (IR) is one of the major underlying causes of metabolic disorders despite its association with several physiological conditions. Metabolic syndrome (MS) is another pathophysiological condition that is associated with IR, hypertension, and obesity. Further, several other pathophysiological disorders/diseases are associated with the insulin malfunctioning, which include polycystic ovary syndrome, neuronal disorders, and cancer. Insulinomas are an uncommon type of pancreatic β-cell-derived neuroendocrine tumor that makes up 2% of all pancreatic neoplasms. Literature revealed that different biochemical events, molecular signaling pathways, microRNAs, and microbiota act as connecting links between insulin disorder and associated pathophysiology such as DM, insuloma, neurological disorder, MS, and cancer. In this review, we focus on the insulin-related disorders and the underlying mechanisms associated with the pathophysiology.

Pancreatic insulinoma: Diagnosis and treatment of a rare tumour with misleading symptoms - A case report

INTRODUCTION

Insulinomas are an uncommon occurrence, with an annual incidence of approximately 4 per million. These functional pancreatic neuroendocrine tumours can present with a myriad of nonspecific symptoms leading to frequent misdiagnoses.

PRESENTATION OF CASE

In this case report is presented a 55-year-old man who was misdiagnosed and managed for a seizure disorder with escalating antiepileptic treatments for 11 months. A thorough history after an attack was the main tool in solving the mystery of his refractory seizures, leading to the discovery of a pancreatic insulinoma. Biochemical tests revealed fasting hypoglycaemia and a relative hyperinsulinemia, and a distal pancreatic lesion measuring approximately 1.8 cm × 1.3 cm was detected on CT, MRI and endoscopic ultrasound. Successful laparoscopic pancreatic left resection led to complete resolution of symptoms and restoration of quality of life to pre-illness levels.

DISCUSSION AND CONCLUSION

Insulinomas have historically been difficult to diagnose because their symptoms mimic neurologic and psychiatric conditions. Patterns of symptom occurrence obtained from a carefully-taken history is the single most important tool in assessing patients with insulinomas, who usually present with unusual and refractory neuropsychiatric conditions.

An Uncommon Cause of Recurrent Presyncope, Dizziness, and Tachycardia: A Case Report of Diffuse, Adult-Onset Nesidioblastosis/Non-Insulinoma Pancreatogenous Hypoglycemia Syndrome (NIPHS)

Neurovegetative and autonomic symptoms are common presentations of various diseases, ranging from psychosomatic to severe organic disorders. A 23-year-old man presented with a history of recurrent presyncope, dizziness, and tachycardia. Repeated diagnostic work-up in various clinical settings could not identify any definite cause for approximately eight years. However, the incidental detection of postprandial and exercise-induced hypoglycemia was suggestive of an insulin-related disorder. A 72 h plasma glucose fasting test revealed endogenous hyperinsulinism. Upon imaging studies, no tumor mass potentially indicating insulinoma could be detected. ⁶⁸Ga-DOTA-Exendin-4 PET/CT showed diffuse tracer enrichment throughout the whole pancreas. A subtotal pancreatectomy was performed, and the diagnosis of diffuse, adult-onset nesidioblastosis was established histopathologically. This corresponds to the clinical findings of a functional β-cell disorder, also known as non-insulinoma pancreatogenous hypoglycemia syndrome (NIPHS). After nine months, the symptoms recurred, making complete pancreatectomy necessary. Postoperative laboratory evaluation exhibited no residual endogenous C-peptide production. This case illustrates the diagnostic challenges in patients presenting with unspecific, neurovegetative and autonomic symptoms with a severe and rare underlying cause.

Diffuse, Adult-Onset Nesidioblastosis/Non-Insulinoma Pancreatogenous Hypoglycemia Syndrome (NIPHS): Review of the Literature of a Rare Cause of Hyperinsulinemic Hypoglycemia

Differential diagnosis of hypoglycemia in the non-diabetic adult patient is complex and comprises various diseases, including endogenous hyperinsulinism caused by functional β-cell disorders. The latter is also designated as nesidioblastosis or non-insulinoma pancreatogenous hypoglycemia syndrome (NIPHS). Clinically, this rare disease presents with unspecific adrenergic and neuroglycopenic symptoms and is, therefore, often overlooked. A combination of careful clinical assessment, oral glucose tolerance testing, 72 h fasting, sectional and functional imaging, and invasive insulin measurements can lead to the correct diagnosis. Due to a lack of a pathophysiological understanding of the condition, conservative treatment options are limited and mostly ineffective. Therefore, nearly all patients currently undergo surgical resection of parts or the entire pancreas. Consequently, apart from faster diagnosis, more elaborate and less invasive treatment options are needed to relieve the patients from the dangerous and devastating symptoms. Based on a case of a 23-year-old man presenting with this disease in our department, we performed an extensive review of the medical literature dealing with this condition and herein presented a comprehensive discussion of this interesting disease, including all aspects from epidemiology to therapy.

Metastatic insulinoma: exploration from clinicopathological signatures and genetic characteristics

Background

Insulinoma is a rare type of pancreatic neuroendocrine tumor with low incidence and low-malignant features. While very few insulinomas present with malignant behaviours, such as lymph node and liver metastasis, only a few studies have focused on this field owing to the limitation of samples. Existing evidence suggests that metastatic insulinoma largely derive from non-functional pancreatic neuroendocrine tumor. However, we found a portion of metastatic insulinomas may derive from non-metastatic insulinomas and explored their clinicopathological signatures and genetic characteristics.

Methods

Four metastatic insulinoma patients with synchronous liver metastasis or lymph node metastasis at the Peking Union Medical College Hospital between October 2016 and December 2018 were enrolled, and whole exon and genome sequencing were performed on fresh frozen tissues and peripheral blood samples. Clinicopathological information and genomic sequencing results were collected and matched to explore the characteristics of the metastatic insulinomas.

Results

These four metastatic insulinoma patients underwent surgery or interventional therapy, and their blood glucose levels immediately increased and maintained within standard range after treatment. For these four patients, the proinsulin/insulin molar ratio <1 and primary tumors were all present as PDX1+, ARX-, and insulin+, which were similar to non-metastatic insulinomas. However, the liver metastasis showed PDX1+ and ARX+, insulin+. Meanwhile, genomic sequencing data showed no recurrently mutations and typical CNV patterns. However, one patient harboured the YY1 T372R mutation, a recurrently mutated gene in non-metastatic insulinomas.

Conclusions

A portion of metastatic insulinomas were largely derived from non-metastatic insulinomas in hormone secretion and ARX/PDX1 expression patterns. Meanwhile, the accumulation of ARX expression may be involved in the progression of metastatic insulinomas.

Indocyanine green fluorescence imaging to localize insulinoma and provide three-dimensional demarcation for laparoscopic enucleation: a retrospective single-arm cohort study

BACKGROUND

Indocyanine green (ICG) fluorescence imaging is a new technology that can improve the real-time location of tumor edges and small nodules during surgery. However, no study has investigated its application in laparoscopic insulinoma enucleation. This study aimed to evaluate the feasibility and accuracy of this method for intraoperative localization of insulinomas and margin assessment during laparoscopic insulinoma enucleation.

MATERIALS AND METHODS

Eight patients who underwent laparoscopic insulinoma enucleation from October 2016 to June 2022 were enrolled. Two methods of ICG administration, ICG dynamic perfusion and three-dimensional (3D) demarcation staining, were utilized in the laparoscopic insulinoma enucleation. Tumor-to-background ratio (TBR) and histopathologic analysis were used to evaluate the feasibility and accuracy of these novel navigation methods in laparoscopic insulinoma enucleation.

RESULTS

All eight enrolled patients underwent both ICG dynamic perfusion and 3D demarcation staining. ICG dynamic perfusion images were available for six of them, among which five tumors could be recognized by TBR (largest TBR in each case 4.42±2.76), while the other could be distinguished by the disordered blood vessels in the tumor area. Seven out of eight specimens had successful 3D demarcation staining (TBR 7.62±2.62). All wound bed margins had negative frozen sections and final histopathologic diagnoses.

CONCLUSIONS

ICG dynamic perfusion may be helpful in observing the abnormal vascular perfusion of tumors, providing similar functionality to intraoperative real-time angiography. ICG injection under the tumor pseudocapsule may be a useful method for acquiring real-time, 3D demarcation for the resection of insulinoma.

Endogenous hyperinsulinemic hypoglycemia: case series and literature review

PURPOSE

Endogenous hyperinsulinemic hypoglycemia (EHH) is an uncommon disease characterized by inappropriately high plasma insulin levels despite low plasma glucose levels. Some rare etiologies can lead to EHH. Correct diagnosis is a prerequisite for treatment. Hence, although challenging, it is crucial for patients with EHH to identify the different causes.

METHODS

We describe a case series of three patients, all of whom had obvious hypoglycemic symptoms and extraordinary hyperinsulinemia. Their plasma glucose, insulin, and C-peptide levels were tested simultaneously when hypoglycemia occurred. Moreover, other biochemical indices and relevant antibody levels were measured and imaging examinations were conducted.

RESULTS

According to their medical history, physical examination, laboratory results, and imaging findings, the three patients were diagnosed with insulinoma, type B insulin resistance syndrome, and insulin autoimmune syndrome. After precise treatments, hypoglycemia was ultimately eliminated.

CONCLUSION

Although these diseases have similar symptoms and biochemical abnormalities, the treatment and prognosis are different. The case series presented here highlights the challenges in the differential diagnosis of EHH. An accurate diagnosis is necessary for hypoglycemia treatment.

C-peptide level concomitant with hypoglycemia gives better performances than insulin for the diagnosis of endogenous hyperinsulinism: a single-center study of 159 fasting trials

INTRODUCTION

Diagnosis of endogenous hyperinsulinism relies on the occurrence of a hypoglycemia, concomitant with inadequate high insulin and C-peptide levels. However, diagnostic cutoffs are not consensual among the different learned societies. The objective of this work was to propose optimized cutoffs for these three parameters for the diagnosis of endogenous hyperinsulinism.

METHODS

All the patients having performed a fasting trial in Cochin Hospital Endocrinology Department between February 2012 and August 2022 were included. The results of glycemia, insulin and C-peptide levels during fasting trial were collected and analyzed.

RESULTS

One hundred and fifty-nine patients were included: 26 with endogenous hyperinsulinism and 133 without endogenous hyperinsulinism. ROC analysis of glycemia nadir during fasting trial identified the value of 2.3 mmol/L as the optimal cutoff, ensuring a sensitivity of 100% associated with a specificity of 81%. ROC analysis of insulin and C-peptide levels concomitant with hypoglycemia <2.3 mmol/L showed very good diagnostic performances of both parameters with respective cutoffs of 3.1 mUI/L (=21.5 pmol/L; sensitivity = 96%; specificity = 92%) and 0.30 nmol/L (sensitivity = 96%; specificity = 100%). Insulin to glycemia ratio as well as C-peptide to glycemia ratio (in pmol/mmol) at the time of glycemia nadir did not show better diagnostic performances than C-peptide alone.

CONCLUSION

A C-peptide level 0.3 nmol/L concomitant with a hypoglycemia <2.3 mmol/L appears as the best criterion to make the diagnosis of endogenous hyperinsulinism. Insulin level can be underestimated on hemolyzed blood samples, frequently observed in fasting trial, and thus shows lower diagnostic performances.

Review of Hematology-Oncology Emergencies for Internal Medicine Residents

The prevalence of cancer continues to grow globally every year. With therapeutic advances over the recent decades, the prevalence of individuals living with cancer continues to increase. Internal medicine residents can see patients admitted to the hospital for cancer-related emergencies. Early identification and appropriate management of these emergencies have been shown to improve mortality and morbidity. In this article, we aim to review the recent updates in the management of commonly encountered oncologic emergencies in the practice of internal medicine residents. This review will cover spinal cord compression, superior vena cava syndrome, tumor lysis syndrome, hypercalcemia, pericardial tamponade, hypoglycemia, hyponatremia, bowel obstruction, increased intracranial pressure, leukostasis, hyperviscosity syndrome, neutropenic fever, and hypersensitivity reactions.

Insulinoma in childhood: a retrospective review of 22 patients from one referral centre

Background

Insulinomas are very rare in childhood with sparse knowledge on the clinical aspects and the presence of Multiple Endocrine Neoplasia type 1 (MEN1).

Methods

We conducted a retrospective review of patients diagnosed with insulinoma between 1995 and 2021, presenting to one referral centre in Russia. Clinical, biochemical, genetic, imaging and histological data were collected. In addition, follow-up and family data were obtained.

Results

A total of twenty-two children aged 5 to 16 years were identified. The median (range) gap between the first hypoglycaemia symptoms and diagnosis was 10 (1-46) months. Twelve children (55%) were misdiagnosed to have epilepsy and were treated with anticonvulsants before hypoglycemia was revealed. Contrast enhanced MRI and/or CT were accurate to localize the lesion in 82% (n=18). Five patients (23%) had multiple pancreatic lesions. All children underwent surgical treatment. The median (range) diameter of removed tumors was 1.5 (0.3-6) cm. Histopathological studies confirmed the presence of insulinoma in all cases. Immunohistochemical studies revealed G2 differentiation grade in 10 out of 17 cases. Two patients were diagnosed with metastatic insulinoma. One of them had metastases at the time of insulinoma diagnosis, while the other was diagnosed with liver metastases eight years after the surgery. Eight children (36%) were found to carry MEN1 mutations, inherited n=5, de novo n=1, no data, n=2. Children with MEN1 had significantly higher number of pancreatic tumors compared to sporadic cases. All of them developed additional MEN1 symptoms during the following 2-13 years. In the five patients with inherited MEN1, seven family members had hitherto undiscovered MEN1 manifestations.

Conclusions

In this large cohort of children with rare pediatric insulinomas, MEN1 syndrome and G2 tumors were frequent, as well as hitherto undiscovered MEN1 manifestations in family members. Our data emphasize the need of genetic testing in all children with insulinoma and their relatives, even in the absence of any other features, as well as the importance of a prolonged follow-up observation.

The Galaninergic System: A Target for Cancer Treatment

Simple Summary

Peptidergic systems play an important role in cancer progression. The galaninergic system (the peptide galanin and its receptors: galanin 1, 2 and 3) is involved in tumorigenesis, the invasion and migration of tumor cells and angiogenesis and it has been correlated with tumor stage/subtypes, metastasis and recurrence rate in many types of cancer. Galanin exerts a dual action in tumor cells: a proliferative or an antiproliferative effect depending on the galanin receptor involved in these mechanisms. Galanin receptors could be used in certain tumors as therapeutic targets and diagnostic markers for treatment, prognosis and surgical outcome. This review shows the importance of the galaninergic system in the development of tumors and suggests future promising clinical antitumor applications using galanin agonists or antagonists.

Abstract

The aim of this review is to show the involvement of the galaninergic system in neuroendocrine (phaeochromocytomas, insulinomas, neuroblastic tumors, pituitary tumors, small-cell lung cancer) and non-neuroendocrine (gastric cancer, colorectal cancer, head and neck squamous cell carcinoma, glioma) tumors. The galaninergic system is involved in tumorigenesis, invasion/migration of tumor cells and angiogenesis, and this system has been correlated with tumor size/stage/subtypes, metastasis and recurrence rate. In the galaninergic system, epigenetic mechanisms have been related with carcinogenesis and recurrence rate. Galanin (GAL) exerts both proliferative and antiproliferative actions in tumor cells. GAL receptors (GALRs) mediate different signal transduction pathways and actions, depending on the particular G protein involved and the tumor cell type. In general, the activation of GAL₁R promoted an antiproliferative effect, whereas the activation of GAL₂R induced antiproliferative or proliferative actions. GALRs could be used in certain tumors as therapeutic targets and diagnostic markers for treatment, prognosis and surgical outcome. The current data show the importance of the galaninergic system in the development of certain tumors and suggest future potential clinical antitumor applications using GAL agonists or antagonists.

EZH2 suppresses insulinoma development by epigenetically reducing KIF4A expression via H3K27me3 modification

Kinesin family member 4A (KIF4A), located in the human chromosome band Xq13.1, is aberrantly overexpressed in various cancers. Our study intended to assess the expression of KIF4A in insulinoma and to gain new insights into the molecular mechanisms of this rare disease. First, KIF4A was significantly recruited in pancreatic endocrine cells relative to other cell types. A significant correlation existed between the overexpression of KIF4A and the poor survival of pancreatic adenocarcinoma patients. As revealed by CCK-8, TUNEL assay, flow cytometry, wound healing, Matrigel-transwell, senescence-associated β-galactosidase staining, ELISA, and subcutaneous tumor formation analysis in nude mice, knocking down KIF4A significantly inhibited the growth and metastasis of insulinoma cells in vivo and in vitro. Mechanistically, we observed that KIF4A promoter sequences had reduced H3K27me3 modifications, and decline in enhancer of zeste homolog-2 (EZH2) expression promoted KIF4A expression by reducing the modification, thus leading to insulinoma. Moreover, EZH2 knockdown-induced insulinoma cell proliferation was dependent on KIF4A overexpression since KIF4A knockdown eradicated shEZH2-induced proliferation of insulinoma cells. In summary, KIF4A was identified as a possible therapeutic target for insulinoma.

Case of Insulinoma in a 2-Months-Old Infant

INTRODUCTION: Insulinoma is congenital hyperinsulinism of infancy (CHI). It is a type of functional neuroendocrine tumor (NET) in the pancreas that manifests with persistent hypoglycemia caused by inappropriately high secretion of insulin (hyperinsulinemia). Comprehensive and multidisciplinary management is required for a better outcome. CASE PRESENTATION: A 2-months-old girl came to the Emergency unit Sanglah Hospital, with a chief complaint of seizure. The patient had a low blood glucose level, high fasting insulin, high LDH, computed tomography of the abdomen result showed isodense heterogeneous lesions border in the cauda pancreas with size 1.32 × 1.24 × 1.35 cm. The anatomy-pathological result showed pancreatic neuroendocrine tumor WHO Grade II, functional, consistent, and clinically to insulinoma on the tail of the pancreas. The patient was treated with hydrocortisone, nifedipine, and octreotide. The patient underwent laparotomy partial pancreatectomy. In post-surgery condition, she had good drink tolerance, no episode of recurrent seizure, and blood glucose was controlled. CONCLUSION: Insulinoma is a rare disease. The diagnosis was challenging. This case report presents the diagnostic work-up and management of a patient with a persistent hypoglycemia condition that was diagnosed as insulinoma.

Canine insulinoma as a model for human malignant insulinoma research: Novel perspectives for translational clinical studies

Insulinomas are considered rare indolent neuroendocrine neoplasms in human medicine, however when metastases occur no curative treatment is available thus, novel therapies are needed. Recently advances have been made in unraveling the pathophysiology of malignant insulinoma still major challenges hinder the development of a functional model to study them. Canine malignant insulinoma have similar recurrence and a poor prognosis as human malignant insulinoma. Additionally, both human and canine patients share extensively the same environment, tend to develop insulinoma seemingly spontaneously with an etiological role for hormones, at a similar incidence and stage of lifespan, with metastasis commonly to liver and regional lymph nodes, which are unresponsive to current therapies. However, the occurrence of metastases in dogs is as high as 95% compared with only 5-16% in human studies. From a comparative oncology perspective, the shared features with human insulinoma but higher incidence of metastasis in canine insulinoma suggests the latter as a model for human malignant insulinomas. With the common purpose of increasing survival rates of human and veterinary patients, in this review we are going to compare and analyze clinical, pathological and molecular aspects of canine and human insulinomas to evaluate the suitability of the canine model for future translational clinical studies.

Multiple endocrine neoplasia 1: a broad overview

This review article discusses the diagnoses and treatment of patients with multiple endocrine neoplasia type 1 (MEN 1). The most common tumors associated with MEN 1 are located in the pancreas, pituitary, and parathyroid glands. Less common tumors include neuroendocrine tumors of the lung and thymus, adrenal tumors, and cutaneous lesions. This article describes the diagnosis, clinical manifestations, treatment, and surveillance of tumors associated with patients who are diagnosed with MEN 1.

Diagnostic and Interventional Role of Endoscopic Ultrasonography for the Management of Pancreatic Neuroendocrine Neoplasms

Pancreatic neuroendocrine neoplasms (PanNENs) are relatively rare, but their incidence has increased significantly in the last decades. Precise diagnosis and prognostic stratification are crucial for proper patient management. Endoscopic ultrasound (EUS) is the modality of choice for diagnosis of solid pancreatic tumors, showing a higher tumor detection rate than other imaging modalities, especially for small size lesions. EUS also serves as a guide for preoperative sampling and other interventions. EUS-tissue acquisition is a safe and highly accurate technique for cyto/histological diagnosis of PanNENs with a well-demonstrated correlation between Ki-67 proliferation index values and tumor grading on EUS and surgical specimens according to the WHO 2017 classification. Furthermore, the possibility of a preoperative EUS-guided fine needle tattooing or fiducial markers placement may help the surgeon to locate small and deep tumors, thus avoiding formal pancreatic resections in favor of parenchymal-sparing surgery. Finally, locoregional ablative treatments using either ethanol injection or radiofrequency ablation have been proposed in recent studies with promising results in order to control symptoms or reduce tumor burden in selected patients unfit for surgery with functioning or non-functioning PanNENs. This article review highlights the current role of EUS in PanNENs management, focusing on the present and future applications of EUS-guided interventions.

Hipoglucemia tumoral dependiente y no dependiente de células β-pancreáticas, un reto diagnóstico

La hipoglucemia es una urgencia médica frecuente que en la mayoría de los casos es secundaria al uso de fármacos hipoglucemiantes, orales o inyectados, indicados en pacientes con diabetes mellitus. No obstante, puede presentarse en forma espontánea y severa relacionándose con múltiples condiciones clínicas, incluyendo las neoplasias. Ante una hipoglucemia de origen paraneoplásico se deben reconocer los mecanismos fisiopatológicos que la generan y establecer el diagnóstico oportuno y preciso para disminuir las complicaciones propias de este síndrome clínico. Presentamos dos pacientes con cuadro de hipoglucemia refractaria al manejo médico inicial, de aparición similar con patologías diferentes. El primer caso corresponde a un paciente con insulinoma y el segundo con un hemangiopericitoma.

Mutation and Expression of Gene YY1 in Pancreatic Neuroendocrine Tumors and Its Clinical Significance

OBJECTIVE

The clinical significance of the YY1 gene mutation and expression in pancreatic neuroendocrine tumors (PNETs) remains unknown. Therefore, this study aimed to comprehensively analyze the somatic mutation of YY1 in the different subtypes of PNETs.

METHODS

A total of 143 PNETs were assessed by Sanger sequencing to identify the somatic mutation of YY1 gene in various subtypes of PNETs. YY1 protein expression was examined in 103 PNETs by immunohistochemical staining and western blot. Gene mutation and its protein expression were correlated with clinicopathologic features.

RESULTS

A recurrent mutation (chr14:100743807C>G) in the YY1 gene was identified in 15 of 83 insulinomas (18%) and in only 1 of 60 noninsulinoma PNETs (1.7%) (P = .0045). The YY1 mutation was not found in MEN1-associated insulinomas. The YY1 mutation in insulinomas was correlated with older age and lower serum glucose levels (age, 57 vs 42.5 years, P = .006; blood glucose, 25.2 vs 33.6 mg/dL, P = .008). YY1 protein expression was found in 100 of 103 PNETs, although expression was weaker in metastases than in localized tumors (P = .036). The stronger expression of YY1 protein was associated with favorable disease-free survival of patients with PNETs (log-rank, P = .011; n = 70). Multivariable statistical analysis showed that YY1 protein expression could be an independent predictor of prognosis.

CONCLUSION

The hotspot YY1 mutation mostly occurred in insulinomas and rarely in noninsulinoma PNETs. The stronger YY1 protein expression was correlated with the better prognosis of PNETs patients.

The regulation of gastric ghrelin secretion

Ghrelin is a gastric hormone with multiple physiological functions, including the stimulation of food intake and adiposity. It is well established that circulating ghrelin levels are closely associated with feeding patterns, rising strongly before a meal and lowering upon food intake. However, the mechanisms underlying the modulation of ghrelin secretion are not fully understood. The purpose of this review is to discuss current knowledge on the circadian oscillation of circulating ghrelin levels, the neural mechanisms stimulating fasting ghrelin levels and peripheral mechanisms modulating postprandial ghrelin levels. Furthermore, the therapeutic potential of targeting the ghrelin pathway is discussed in the context of the treatment of various metabolic disorders, including obesity, type 2 diabetes, diabetic gastroparesis and Prader-Willi syndrome. Moreover, eating disorders including anorexia nervosa, bulimia nervosa and binge-eating disorder are also discussed.

Ectopic insulin secretion by a large-cell neuroendocrine carcinoma of the cervix

In patients presenting with hyperinsulinemic hypoglycemia with a nonpancreatic neuroendocrine tumor, the diagnosis of an ectopic insulin-secreting tumor should be considered, and investigated further with confirmatory insulin staining.

Chromogranin A: A Valuable Serum Diagnostic Marker for Non-Insulinoma Neuroendocrine Tumors of the Pancreas in a Chinese Population

Background

Pancreatic neuroendocrine tumors (P-NETs) are uncommon neoplasms, with few studies to date assessing serum biomarkers for the diagnosis of P-NETs. This study assessed the ability of serum chromogranin A (CgA) concentrations to distinguish P-NETs from other pancreatic lesions in a Chinese population and to determine the histological grades of P-NETs.

Material/Methods

This prospective study enrolled 165 patients, including 73 with proven P-NETs, 60 with malignant tumors of the pancreas, and 32 with benign lesions of the pancreas. Serum CgA concentrations were measured by ELISA.

Results

Serum CgA concentrations were significantly higher in patients with P-NET than in patients with other pancreatic malignancies and benign lesions (P<0.001), but did not differ significantly in the latter 2 groups (P=0.827). Serum CgA concentrations were significantly higher in patients with non-insulinoma P-NETs than in the other groups (P<0.001), but did not differ significantly in patients with insulinoma and patients with non-P-NETs (P=0.668). Receiver operating characteristic (ROC) curves revealed that a serum CgA concentration of 77.8 ng/ml could distinguish patients with non-insulinoma P-NETs from patients with non-P-NETs, with a sensitivity of 96.7%, a specificity of 76.1%, and an area under the ROC curve of 0.897. In patients with P-NETs, multifactor analysis showed that the non-insulinoma subtype and the presence of liver metastases were associated with elevated serum CgA (both p<0.001).

Conclusions

Serum CgA concentration may be a valuable diagnostic biomarker for non-insulinoma P-NETs. Elevated serum CgA is likely associated with liver metastases.

Insulinoma presenting with postprandial hypoglycemia and a low body mass index: A case report

BACKGROUND

Insulinomas are the most common type of functioning endocrine neoplasms of the pancreas presenting hypoglycemic symptoms. Patients characteristically develop symptoms while fasting, but some patients have reported symptoms only in the postprandial state. Repeated and prolonged hypoglycemic episodes can reduce the awareness of adrenergic symptoms, and patients may have amnesia, which delays diagnosis.

CASE SUMMARY

We describe a case of a 24-year-old underweight patient who showed hypoglycemic symptoms for almost 6 years. Although patients with insulinoma characteristically develop symptoms while fasting, this young man had hypoglycemic symptoms up to one hour postprandially, especially after high-sugar meals and after physical activity. The fasting tests and imaging methods performed at local hospitals were evaluated as negative for abnormal results. However, brown adipose tissue exhibited increased metabolic activity, and some muscle groups had histological changes as indicated by positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose integrated with computed tomography. Glycogen deficiency was also histologically confirmed. The patient’s symptoms progressed over the years and occurred more frequently, i.e., several times a month, and the patient had reduced awareness of adrenergic symptoms. The follow-up fasting test was positive, and the imaging results showed a tumor in the head of the pancreas. The patient underwent laparotomy with enucleation of the insulinoma.

CONCLUSION

Weight gain and fasting hypoglycemia are not necessarily characteristics of insulinoma. In prolonged cases, adrenergic symptoms can be suppressed.

Surgical management of primary pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (PanNETs) are the second most common malignancy of the pancreas, and their incidence is increasing. PanNETs are a diverse group of diseases which range from benign to malignant, can be sporadic or associated with genetic mutations, and be functional or nonfunctional. In as much, the treatment and management of PanNETs can vary from a "Wait and See" approach to orthotopic liver transplantation (OLT). Despite this, surgical resection is still the primary treatment modality to achieve cure. This review focuses on the surgical management of PanNETs.

Plasma levels of acylated ghrelin in patients with insulinoma and expression of ghrelin and its receptor in insulinomas

BACKGROUND

Insulinoma is a subtype of pancreatic neuroendocrine tumors. Many patients with insulinoma are obese due to frequent food intake. Ghrelin is associated with obesity and blood levels of insulin. It is not clear if plasma levels of ghrelin in insulinoma patients correlate with hyperinsulinemia and obesity. Expression of ghrelin and its receptor has not been well demonstrated in insulinoma.

OBJECTIVE

To study if plasma levels of ghrelin is associated with obesity and hyperinsulinemia or hyperproinsulinemia in patients with insulinoma, and to detect the expression of ghrelin and its receptor in insulinoma.

METHODS

Plasma levels of acylated ghrelin, insulin, and proinsulin were measured in 37 patients with insulinoma and 25 controls by ELISA. Expression of ghrelin and its receptor GHS-R1A was examined in 20 insulinoma and paired pancreatic specimens by immunostaining. P ≤ 0.05 was considered significant.

RESULTS

The plasma levels of acylated ghrelin in patients with insulinoma were significantly lower than that in the controls (median 15 pg/ml vs. 19 pg/ml, respectively, P = 0.016). The reduced plasma levels of acylated ghrelin in patients were significantly correlated with obesity, hyperinsulinemia, and hyperproinsulinemia (P = 0.029 and P = 0.028, respectively). Expression of ghrelin and its receptor GHS-R1A was shown in the majority of insulinoma specimens. The expression of GHS-R1A was positively correlated with ghrelin expression in insulinoma (P = 0.014).

CONCLUSIONS

Plasma levels of acylated ghrelin decreased in patients with insulinoma, probably due to the hyperinsulinemia and obesity in the patients. Expression of both ghrelin and its receptor is common in insulinoma.

Incidence of postoperative complications and outcome of 48 dogs undergoing surgical management of insulinoma

BACKGROUND

Information regarding outcome of dogs undergoing surgical management for insulinoma is based on studies of a small number of dogs.

OBJECTIVES

To report the outcomes of dogs undergoing surgery as treatment for insulinoma, the prevalence of postoperative diabetes mellitus (DM) in this group and to determine if development of DM can be predicted.

ANIMALS

Forty-eight client-owned dogs, with a histopathological diagnosis of insulinoma, from three European referral hospitals.

METHODS

Retrospective observational study. Dogs were identified from a search of electronic hospital records. Cox's regression was used to determine factors associated with postoperative survival and relapse, and logistic regression was used to determine factors associated with the development of DM.

RESULTS

Median survival time (MST) was 372 days (range 1-1680 days), with dogs with stage I disease having the longest survival time. Stage I dogs had MST of 652 days (range 2-1680 days), whereas dogs with either stage II or III disease had MST of 320 days (range 1-1260 days; P = 0.045). Postoperative hyperglycemia was identified in 33% (16/48) of the dogs, of which 9 (19% of the total population) developed persistent DM. No factors that could be used as predictors for development of DM were identified.

CONCLUSIONS AND CLINICAL IMPORTANCE

Stage of disease and postoperative hypoglycemia were associated with greater odds of relapse and decreased survival time; these could be used when discussing prognosis. In this study, postoperative DM developed more commonly than previously reported, but no factors were identified that might be useful predictors.

The functioning side of the pancreas: a review on insulinomas

PURPOSE

Insulinomas are a rare type of neuroendocrine tumors, originating in the pancreas, difficult to diagnose and to treat. Due to its rarity, insulinomas are a not well-known pathological entity; thus, the diagnostic process is frequently a medical challenge with many possible differential diagnoses. The diagnostic process varies between non-invasive procedures, such as the fasting test or imaging techniques, and invasive ones. Insulinomas are rarely malignant, but the glycemic imbalance correlated with this tumor can frequently alter the quality of life of the patients and the consequent hypoglycemia can be extremely dangerous. Moreover, insulinomas can be associated with different genetic syndromes, such as Multiple Endocrine Neoplasia 1, accompanied by other specific symptoms. There are many different treatment strategies, depending on the need to control symptoms or control diseases progression, the only curative one being surgery.

METHODS AND RESULTS

We reviewed the evidences present in the literature on insulinomas and reported its main clinical characteristics and management strategies.

CONCLUSION

The aim of this review of the literature is to present the current knowledge on insulinomas, exploring the main clinical characteristics, the diagnostic tools, and the therapeutic strategies.

Interplay Between Diabetes and Pancreatic Ductal Adenocarcinoma and Insulinoma: The Role of Aging, Genetic Factors, and Obesity

Epidemiologic analyses have shed light on an association between type 2 diabetes (T2D) and pancreatic ductal adenocarcinoma (PDAC). Recent data also suggest a potential relationship between T2D and insulinoma. Under rare circumstances, type 1 diabetes (T1D) can also be implicated in tumorigenesis. The biological mechanisms underlying such relationships are extremely complex. Some genetic factors contributing to the development of T2D are shared with pancreatic exocrine and endocrine tumors. Obesity and overweight can also contribute to the initiation and severity of T2D, while aging may influence both endocrine and exocrine tumors. Finally, pharmacological treatments of T2D may have an impact on PDAC. On the other hand, some treatments for insulinoma can trigger diabetes. In the present minireview, we discuss the cellular and molecular mechanisms that could explain these interactions. This analysis may help to define new potential therapeutic strategies.

Gastroparesis and Dumping Syndrome: Current Concepts and Management

Gastroparesis and dumping syndrome both evolve from a disturbed gastric emptying mechanism. Although gastroparesis results from delayed gastric emptying and dumping syndrome from accelerated emptying of the stomach, the two entities share several similarities among which are an underestimated prevalence, considerable impairment of quality of life, the need for a multidisciplinary team setting, and a step-up treatment approach. In the following review, we will present an overview of the most important clinical aspects of gastroparesis and dumping syndrome including epidemiology, pathophysiology, presentation, and diagnostics. Finally, we highlight promising therapeutic options that might be available in the future.

Alcohol-free EUS-guided chemoablation of multiple pancreatic insulinomas

Background and study aims  Endoscopic ultrasound (EUS)-guided chemoablation with ethanol lavage, followed by infusion with paclitaxel, has been found to be effective for treatment of mucinous pancreatic cysts. However, there are notable adverse events (AEs) associated with ethanol and its undesirable inflammatory effects on local tissue and vessels. The recent ChARM trial demonstrated that removing ethanol from the cyst ablation process resulted in equivalent efficacy while significantly reducing associated AEs. Encouraged by these results, we speculated that alcohol-free chemoablation can be applied to treatment of solid tumors, as described in our case with a patient with severe and symptomatic recurrent hypoglycemia in the setting of multifocal insulinomas. As a result, the patient saw a significant reduction in symptoms. EUS-guided alcohol-free chemoablation may represent a new alternative to previously established therapies that will ultimately reduce risk of AEs.

EUS-guided lauromacrogol ablation of insulinomas: a novel treatment

BACKGROUND AND AIMS

EUS-guided ablation with ethanol has been used to treat insulinoma since 2006 as a minimally invasive alternative for those who are unwilling or unsuitable for surgeries. However, pancreatic fistula, pancreatitis and other adverse effects were found after the procedure in these patients. Herein, we aimed to find a novel feasible injection.

METHODS

Seven patients with different chief complaints were diagnosed with insulinoma by symptoms, lab results and pathology results from EUS fine needle aspiration. All the patients refused to have surgeries and were treated by EUS-guided ablation with lauromacrogol. The injection volume was calculated by tumor size. All the patients were followed up by at least 1 month to see if there is any adverse effect. Blood glucose (BG), insulin and C-peptide levels were monitored before and after the procedure.

RESULTS

Insulinoma size ranged from 0.76 cm ×0.84 cm to 3.39 cm ×1.84 cm. With a mean injection volume of 1.9 ml (range from 0.9 to 3.9 ml), all the patients showed relief in symptoms after the procedure. During the follow up, their BG, insulin and C-peptide levels went back to normal. None of the patients had any adverse effect.

CONCLUSIONS

EUS-guided ablation with lauromacrogol showed good treatment results and received no adverse effect after the procedure. Hence, we consider it as an effective and safe method to treat insulinoma.

Notch pathway inhibition targets chemoresistant insulinoma cancer stem cells

Insulinomas (INS) are the most common neuroendocrine pancreatic tumours in humans and dogs. The long-term prognosis for malignant INS is still poor due to a low success rate of the current treatment modalities, particularly chemotherapy. A better understanding of the molecular processes underlying the development and progression of INS is required to develop novel targeted therapies. Cancer stem cells (CSCs) are thought to be critical for the engraftment and chemoresistance of many tumours, including INS. This study was aimed to characterise and target INS CSCs in order to develop novel targeted therapies. Highly invasive and tumourigenic human and canine INS CSC-like cells were successfully isolated. These cells expressed stem cell markers (OCT4, SOX9, SOX2, CD133 and CD34), exhibited greater resistance to 5-fluorouracil (5-FU) and demonstrated a more invasive and tumourigenic phenotype in vivo compared to bulk INS cells. Here, we demonstrated that Notch-signalling-related genes (NOTCH2 and HES1) were overexpressed in INS CSC-like cells. Protein analysis showed an active NOTCH2-HES1 signalling in INS cell lines, especially in cells resistant to 5-FU. Inhibition of the Notch pathway, using a gamma secretase inhibitor (GSI), enhanced the sensitivity of INS CSC-like cells to 5-FU. When used in combination GSI and 5-FU, the clonogenicity in vitro and the tumourigenicity in vivo of INS CSC-like cells were significantly reduced. These findings suggested that the combined strategy of Notch signalling inhibition and 5-FU synergistically attenuated enriched INS CSC populations, providing a rationale for future therapeutic exploitation.

Hypoglycemia in a Patient With a Polyhormonal Pancreatic Neuroendocrine Tumor With Evidence of Endocrine Progenitors

A 55-year-old woman with a large polyhormonal neuroendocrine tumor with unusual pathology is described. The patient presented with intermittent neuroglycopenic symptoms between more protracted asymptomatic periods occurring over the preceding 4 years. During a diagnostic 72-hour inpatient fast, she exhibited hypoglycemia at 70 hours after initiation. On computed tomography scan, a 6-cm mass was identified at the pancreatic head. The patient underwent a pylorus-preserving pancreaticoduodenectomy, and pathology was positive for cells staining for pancreatic polypeptide, insulin, and occasional double hormone (insulin plus pancreatic polypeptide)-positive cells. In addition, the tumor exhibited broad staining for ALDH1A3, a new marker of endocrine progenitors. This case serves to highlight the clinical and pathologic variability of insulin-producing tumors and raises the potential for cells in these tumors to exhibit hormone interconversion and progenitor-like states.

Surgical Therapy of Sporadic Pancreatic Neuroendocrine Neoplasias G1/G2

Background

Pancreatic neuroendocrine neoplasias (pNENs) are uncommon but fascinating tumors with an annual incidence of 1 per 100,000 people. pNENs present either as functional tumors, causing specific hormonal syndromes like Zollinger-Ellison syndrome (ZES) or organic hyperinsulinism, or as non-functional pancreatic tumors (NF-pNENs). The natural history of pNENs is highly variable. 90% of all insulinomas or small NF- pNENs are readily curable by surgical resection. Most other functional and late detected NF-pNENs have a less favorable chance for cure.

Methods

A systematic review of the literature was performed to identify the current state of the art with regard to the key issues of surgery in pNEN G1/G2.

Results

This article provides a comprehensive review of the current literature addressing the current challenges in pNEN surgery.

Conclusion

Patients with completely resected tumors generally have a good prognosis, and an aggressive surgical approach combined with conservative treatment options in patients with advanced disease rarely provides cure but often results in long-term survival.

Insulinoma Presenting with Reactive Hypoglycemia: Evaluating the Effect of Tumor Resection via Continuous Glucose Monitoring

A 71-year-old woman previously diagnosed with reactive hypoglycemia was transferred to our emergency unit because of loss of consciousness. Her plasma glucose level was 27 mg/dL, and continuous glucose monitoring (CGM) revealed postprandial asymptomatic hypoglycemia. A hypervascular tumor was identified via computed tomography in the distal pancreas, and the diagnosis of insulinoma was confirmed using the selective arterial calcium stimulation test. Although no episodes of hypoglycemia were observed during CGM after resection, a pathological examination identified regional lymph node metastasis. It is important to consider insulinoma as a cause of postprandial hypoglycemia, and CGM is useful for evaluating treatment outcomes.

[Early endocrine neoplasia of the pancreas]

Pancreatic endocrine neoplasias (pNENs) are uncommon but fascinating tumors with a rising incidence. In accordance to its location, size and grading, the decision to operate the patient should always be made in an interdisciplinary approach. This article provides a comprehensive review of the current literature addressing the current challenges in pNEN surgery and shows that patients with completely resected small pNENs generally have an excellent prognosis, but also that surveillance may be a powerful tool.

Evolving management of insulinoma: Experience at a tertiary care centre

BACKGROUND & OBJECTIVES

Since our previous study in 2006, several new modalities for localization of cause of endogenous hyperinsulinemic hypoglycaemia such as multiphasic computed tomography (CT), multiphasic magnetic resonance imaging (MRI), endoscopic ultrasound (EUS), intraoperative ultrasound, and intra-arterial calcium infusion with arterial stimulation venous sampling (ASVS) have become available. Therefore, to evaluate the relative usefulness of various imaging modalities to guide future management in terms of diagnosis and patient care, we analyzed presentation and management of patients of endogenous hyperinsulinemic hypoglycaemia.

METHODS

In this retrospective study, medical records of patients admitted with endogenous hyperinsulinemic hypoglycaemia were retrieved. Data pertaining to clinical features, diagnosis, imaging, surgery and patient outcome were extracted. The localization of insulinoma by preoperative imaging techniques was compared with the findings at surgery to assess the accuracy of localization.

RESULTS

Fasting hypoglycaemia was present in all, and post-prandial hypoglycaemia (plasma glucose ≤50 mg/dl within four hours of meal) in 25.8 per cent. Mean duration of symptoms before reaching a diagnosis of hyperinsulinemic hypoglycaemia was 3.9 years. Mean duration of provocative fast was 21.8 h (range 6-48 h). Among the currently used imaging modalities, the sensitivity of localizing tumour was 79.3 per cent for multiphasic CT, 85 per cent for multiphasic MRI and 95 per cent for EUS. EUS detected tumour missed by both CT and MRI. All, except one of the operated patients, were cured by surgery.

INTERPRETATION & CONCLUSIONS

Our results suggest that patients with insulinoma have a varied presentation. Multiphasic contrast-enhanced MRI/CT scan, EUS and ASVS may be complimentary in pre-operative localization.

Hypoglycemia and decreased insulin requirement caused by malignant insulinoma in a type 1 diabetic patient: when the hoof beats are from a zebra, not a horse

Insulinomas are uncommon tumors, and in patients with diabetes mellitus they are extremely rare. We describe a patient with type 1 diabetes who developed malignant insulinoma. When hypoglycemic episodes persist in a patient with diabetes and treatment‐induced and other causes of hypoglycemia have been ruled out, an insulin‐producing tumor should be considered.

Emergencies in Hematology and Oncology

The development of medical emergencies related to the underlying disease or as a result of complications of therapy are common in patients with hematologic or solid tumors. These oncological emergencies can occur as an initial presentation or in a patient with an established diagnosis and are encountered in all medical care settings, ranging from primary care to the emergency department and various subspecialty environments. Therefore, it is critically important that all physicians have a working knowledge of the potential oncological emergencies that may present in their practice and how to provide the most effective care without delay. This article reviews the most common oncological emergencies and provides practical guidance for initial management of these patients.

Dumping syndrome after esophageal, gastric or bariatric surgery: pathophysiology, diagnosis, and management

BACKGROUND

Dumping syndrome, a common complication of esophageal, gastric or bariatric surgery, includes early and late dumping symptoms. Early dumping occurs within 1 h after eating, when rapid emptying of food into the small intestine triggers rapid fluid shifts into the intestinal lumen and release of gastrointestinal hormones, resulting in gastrointestinal and vasomotor symptoms. Late dumping occurs 1-3 h after carbohydrate ingestion, caused by an incretin-driven hyperinsulinemic response resulting in hypoglycemia. Clinical recommendations are needed for the diagnosis and management of dumping syndrome.

METHODS

A systematic literature review was performed through February 2016. Evidence-based medicine was used to develop diagnostic and management strategies for dumping syndrome.

RESULTS

Dumping syndrome should be suspected based on concurrent presentation of multiple suggestive symptoms after upper abdominal surgery. Suspected dumping syndrome can be confirmed using symptom-based questionnaires, glycemia measurements and oral glucose tolerance tests. First-line management of dumping syndrome involves dietary modification, as well as acarbose treatment for persistent hypoglycemia. If these approaches are unsuccessful, somatostatin analogues should be considered in patients with dumping syndrome and impaired quality of life. Surgical re-intervention or continuous enteral feeding may be necessary for treatment-refractory dumping syndrome, but outcomes are variable.

CONCLUSIONS

Implementation of these diagnostic and treatment recommendations may improve dumping syndrome management.

Surgical management of neuroendocrine tumors

During the last decades an increase in the incidence of neuroendocrine tumors (NETs) was observed. Gastroenteropancreatic NETs represent the majority of NETs. Compared with their epithelial counterpart they usually have a more indolent behaviour and surgical resection improves survival. Tumor diameter is one of the main parameter in the decision making process for nonfunctioning forms. Generally, small lesions can be treated conservatively whereas larger tumors should be treated with standard surgical resection and lymphadenectomy. Functioning tumors should be resected regardless the dimension of the lesion. Locally advanced and metastatic disease should be also treated with extended resections, keeping in consideration the grading, size, Ki67, and presence of extra-abdominal disease. In the case of metastases the panel of operative treatment includes resection, ablation, up to liver transplantation.

Synchronous Nesidioblastosis, Endocrine Microadenoma, and Intraductal Papillary Mucinous Neoplasia in a Man Presenting With Hyperinsulinemic Hypoglycemia

Herein, we report the first case of concomitant nesidioblastosis, pancreatic neuroendocrine tumor, and intraductal papillary mucinous neoplasia. The combination is significant as each of these pathological entities is independently very rare. The patient was a 33-year-old man who presented with symptomatic hyperinsulinemic hypoglycemia and no risk factors for pancreatic disease. Abdominal imaging showed an isolated 12 mm pancreatic lesion, whilst selective arterial calcium stimulation testing demonstrated multiple territories of insulin excess. He proceeded to subtotal pancreatectomy. Histopathology revealed an endocrine microadenoma, α and β cell nesidioblastosis, and multifocal intraductal papillary mucinous neoplasia. The endocrine microadenoma and nesidioblastosis stained for insulin, suggesting both likely contributed to hypoglycemia. Glucagon immunohistochemistry was also positive, though there were no clinical features of glucagon excess. Hypoglycemia resolved postoperatively. This case and other evidence from the literature suggest that hyperplasia and neoplasia may occur sequentially in the pancreas, and that endocrine and exocrine tumorigenesis may be linked in some individuals. Further study is required to identify a unifying mechanism, and to elucidate potential ramifications in the management of patients with pancreatic neoplasms.

Patient with neuropsychiatric symptoms and insulinoma of difficult preoperative localization

This paper describes the case of a patient with neuropsychiatric<br />symptoms who was diagnosed with hyperinsulinemic<br />hypoglycemia with high suspicion of insulinoma, even after<br />conventional diagnostic imaging was unable to locate it. A<br />selective angiography of the pancreatic arteries and a calcium<br />stimulation test were conducted to determine its location.<br />The patient underwent a distal pancreatectomy using an<br />intraoperative ultrasound, resulting in the disappearance of<br />her symptoms.

Diagnostic yield of endoscopic ultrasound in patients with hypoglicemia and insulinoma suspected

BACKGROUND AND OBJECTIVES

Noninvasive imaging techniques have shown limitations to identify insulinomas. In few studies reported so far, endoscopic ultrasound (EUS) has proven to be able to locate lesions. The aim of this study was to compare the performance of computed tomography versus EUS for the detection of insulinomas.

MATERIALS AND METHODS

In a retrospective manner prospectively collected data were analyzed. Patients with hypoglucemia and hyperinsulinemia were included. Diagnostic yield was measured in relationship to sensitivity, specificity, positive predictive value, negative predictive value and accuracy. Surgical specimens were considered the gold standard.

RESULTS

Sensitivity, positive predictive value, and accuracy of EUS was 100%, 95.4% and 95.4%, respectively. In the case of CT the sensitivity was 60%, specificity 100%, positive predictive value 100%, negative predictive value 7%, and accuracy were 68%.

CONCLUSIONS

EUS is useful in the preoperative assessment of patients with hypoglycemia and serum hyperinsulinemia.