Therapies for the medical management of persistent hypoglycaemia in two cases of inoperable malignant insulinoma

68Ga-NODAGA-Exendin-4 PET/CT Findings in a Case of Metastatic Insulinoma With Refractory Hypoglycemia Controlled by 90Y Transarterial Radioembolization

ABSTRACT

Metastatic insulinomas can cause recurrent hypoglycemia requiring continuous IV glucose infusion. Various medical and chemotherapeutic treatment options are used to reduce the patient's risk of death due to hypoglycemia. Treatment-resistant hepatic metastatic insulinomas may benefit clinically from 90Y transarterial radioembolization therapy. In this case, we present a case of liver metastatic insulinoma that achieved clinical improvement after 2 cycles of 90Y microspheres transarterial radioembolization, and the presence of active metastases was demonstrated with 68Ga-NODAGA-exendin-4 PET/CT imaging.

Peptide Receptor Radionuclide Therapy Is Effective for Clinical Control of Symptomatic Metastatic Insulinoma: A Long-Term Retrospective Analysis

Metastatic insulinoma is a rare malignant neuroendocrine tumor characterized by inappropriate insulin secretion, resulting in life-threatening hypoglycemia, which is often difficult to treat. There is currently very limited information about the efficacy of peptide receptor radionuclide therapy (PRRT) for clinical control of hypoglycemia. The aim of this long-term retrospective study was to evaluate the therapeutic efficacy of PRRT for improving hypoglycemia, to evaluate the change of medication after PRRT, and to calculate progression-free survival (PFS) and overall survival (OS). Methods: Inclusion criteria were histologically proven somatostatin receptor-positive metastatic malignant insulinoma and at least 2 cycles of [90Y]Y-DOTATOC or [177Lu]Lu-DOTATOC therapy from early 2000 to early 2022. A semiquantitative scoring system was used to quantify the severity and frequency of hypoglycemic episodes under background antihypoglycemic therapy (somatostatin analog, diazoxide, everolimus, corticosteroids): score 0, no hypoglycemic episodes; score 1, hypoglycemic events requiring additional conservative treatment with optimization of nutrition; score 2, severe hypoglycemia necessitating hospitalization and combined medication or history of hypoglycemic coma. Hypoglycemic score before and after PRRT was analyzed. Time of benefit was defined as a time range of fewer hypoglycemic episodes in the observation period than at baseline. Information on antihypoglycemic medication before and after therapy, PFS, and OS was recorded. Results: Twenty-six of 32 patients with a total of 106 [90Y]Y-DOTATOC/[177Lu]Lu-DOTATOC cycles were included. The average observation period was 21.5 mo (range, 2.3-107.4 mo). Before therapy, 81% (n = 21) of the patients had a hypoglycemia score of 2 and 19% (n = 5) had a score of 1. After PRRT, 81% of patients (n = 21) had a decreased score, and the remaining 5 patients showed a stable situation. There was temporary worsening of hypoglycemia just after injection of [90Y]Y-DOTATOC/[177Lu]Lu-DOTATOC in 19% of patients. The average time of benefit in the observation period was 17.2 mo (range, 0-70.2 mo). Antihypoglycemic medication reduction was achieved in 58% (n = 15) of patients. The median OS and PFS after the start of PRRT were 19.7 mo (95% CI, 6.5-32.9 mo) and 11.7 mo (95% CI, 4.9-18.5 mo), respectively. Conclusion: To our knowledge, our study included the largest cohort of patients with malignant insulinoma to be evaluated. Long-lasting symptom control and reduction of antihypoglycemic medications were shown in most patients after late-line PRRT.

Case Report: Hypoglycemia Due to Metastatic Insulinoma in Insulin-Dependent Type 2 Diabetes Successfully Treated With 177 Lu-DOTATATE

We describe a 96-year-old man with insulin-dependent type 2 diabetes mellitus who, despite insulin cessation, presented with recurrent hypoglycemia associated with confirmed inappropriate endogenous hyperinsulinemia. ⁶⁸Ga-DOTATATE-PET/CT scans demonstrated increased uptake in the pancreatic tail with multiple large intensely active liver metastases. Liver biopsy confirmed the diagnosis of well-differentiated metastatic neuroendocrine tumor. He was unsuitable for surgical resection and long-acting somatostatin analog therapy was ineffective. Subsequent management with four cycles of Lutate [177-Lutetium-DOTA⁰-Tyr³-octreotate (¹⁷⁷Lu-DOTATATE)] resulted in resolution of hypoglycemia and ongoing clinical, biochemical, and radiological response 6 years after. This case is unique due to not only the paradoxical entity of insulinoma in insulin-dependent diabetes but also the positive sustained outcome after ¹⁷⁷Lu-DOTATATE, given that unresectable metastatic insulinoma carries a poor prognosis. We review published cases of metastatic insulinoma in patients with diabetes mellitus as well as the literature to-date investigating efficacy and safety of Lutate therapy in metastatic insulinoma.

Carcinoid Syndrome and Hyperinsulinemic Hypoglycemia Associated with Neuroendocrine Neoplasms: A Critical Review on Clinical and Pharmacological Management

The carcinoid syndrome (CS) and hyperinsulinemic hypoglycemia (HH) represent two of the most common clinical syndromes associated with neuroendocrine neoplasms (NENs). The former is mainly related to the serotonin secretion by a small bowel NEN, whereas the latter depends on an insulin hypersecretion by a pancreatic insulinoma. Both syndromes/conditions can affect prognosis and quality of life of patients with NENs. They are often diagnosed late when patients become strongly symptomatic. Therefore, their early detection and management are a critical step in the clinical management of NEN patients. A dedicated and experienced multidisciplinary team with appropriate therapeutic strategies is needed and should be encouraged to optimize clinical outcomes. This review aims to critically analyze clinical features, evidence and treatment options of CS and HH and therefore to improve their management.

Management of refractory hypoglycaemia in a metastatic neuroendocrine tumour co-secreting serotonin and insulin

A 27-year-old otherwise healthy man of African descent presented to the hospital with initial symptoms of carcinoid syndrome that later evolved into symptoms of hyperinsulinemic hypoglycaemia. Investigations revealed a metastatic neuroendocrine tumour (NET), co-secreting both serotonin and insulin. Management involved a multimodal approach in an attempt to reduce tumour burden and achieve euglycaemia, which proved to be a significant challenge in the face of refractory hypoglycaemia despite the administration of multiple prohyperglycaemic agents in combination. Unfortunately, given the burden of metastatic disease and multiple medical complications that ensued, the patient passed away. This case highlights the clinical history of a NET co-secreting serotonin and insulin, the use of combination therapy in the treatment of refractory hypoglycaemia in a metastatic insulin-producing tumour and emerging therapeutic modalities in the treatment of these rare malignancies.

The use of diazoxide in the management of spontaneous hypoglycemia in patients with ESRD

Although diabetes remains the number one cause of renal failure nationwide, spontaneous hypoglycemia in patients with CKD has also been described in the absence of exogenous insulin or any other diabetes treatment. Decreased renal gluconeogenesis and impaired renal insulin clearance are underlying mechanisms of hypoglycemia in individuals with ESRD. Diazoxide was originally approved as an anti-hypertensive medication, but also is known to bind ATP-sensitive K channels in the beta cells of the pancreas, ultimately leading to inhibition of insulin release. We detail six cases of ESRD-associated hypoglycemia which responded to treatment with diazoxide therapy.

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.

Gamma Emitters in Pancreatic Endocrine Tumors Imaging in the PET Era: Is there a Clinical Space for 99mTc-peptides?

Background:

Pancreatic Neuroendocrine Tumors (PNETs) are rare neoplasms, sporadic or familial, even being part of a syndrome. Their diagnosis is based on symptoms, hormonal disorders or may be fortuitous. The role of Nuclear Medicine is important, mainly because of the possibility of a theranostic strategy. This approach is allowed by the availability of biochemical agents, which may be labeled with radionuclides suitable for diagnostic or therapeutic purposes, showing almost identical pharmacokinetics. The major role for radiopharmaceuticals is connected with radiolabeled Somatostatin Analogues (SSA), since somatostatin receptors are highly expressed on some of the neoplastic cell types.

Discussion:

Nowadays, in the category of radiolabeled SSA, although 111In-pentetreotide, firstly commercially proposed, is still used, the best choice for diagnosis is related to the so called DOTAPET radiotracers labeled with 68-Gallium (Ga), such as 68Ga-DOTATATE, 68Ga-DOTANOC, and 68Ga-DOTATOC. More recently, labeling with 64-Copper (Cu) (64Cu-DOTATATE) has also been proposed. In this review, we discuss the clinical interest of a SAA (Tektrotyd©) radiolabeled with 99mTc, a gamma emitter with better characteristics, with respect to 111Indium, radiolabeling Octreoscan ©. By comparing both pharmacokinetics and pharmacodynamics of Octreoscan©, Tektrotyd© and PET DOTA-peptides, on the basis of literature data and of our own experience, we tried to highlight these topics to stimulate further studies, individuating actual clinical indications for all of these radiotracers.

Conclusion:

In our opinion, Tektrotyd© could already find its applicative dimension in the daily practice of NETs, either pancreatic or not, at least in centers without a PET/CT or a 68Ga generator. Because of wider availability, a lower cost, and a longer decay, compared with respect to peptides labeled with 68Ga, it could be also proposed, in a theranostic context, for a dosimetry evaluation of patients undergoing Peptide Receptor Radionuclide Therapy (PRRT), and for non-oncologic indications of radiolabelled SSA. In this direction, and for a more rigorous cost/effective evaluation, more precisely individuating its clinical role, further studies are needed.

LONG-TERM EFFECT OF 177LU-DOTATATE ON SEVERE AND REFRACTORY HYPOGLYCEMIA ASSOCIATED WITH MALIGNANT INSULINOMA

Objective

Malignant insulinoma is an extremely uncommon tumor that is usually accompanied by severe hypoglycemia that is difficult to manage. At this time, the long-term effect of ¹⁷⁷Lu-DOTATATE (lutetium [Lu-177]-DOTA-Tyr3-octreotate) on this tumor is not well known.

Methods

We report a case of severe, life-threatening, and refractory hypoglycemia associated with malignant insulinoma treated with ¹⁷⁷Lu-DOTATATE.

Results

A 51-year-old woman was referred because of severe, life-threatening, and refractory hypoglycemia due to malignant insulinoma. The patient had been treated unsuccessfully with chemotherapy, targeted therapies, and symptomatic therapy with diazoxide, steroids, and somatostatin analogues without success. ¹⁷⁷Lu-DOTATATE adequately controlled her hypoglycemia after the other conventional treatments failed.

Conclusion

¹⁷⁷Lu-DOTATATE was effective in providing rapid and long-term symptomatic control of the hypoglycemia and significantly improved the quality of life of the patient.

The Effect of Everolimus on Refractory Hypoglycemia in a Patient with Inoperable Metastatic Insulinoma Evaluated by Continuous Glucose Monitoring

An 84-year-old Japanese woman with metastatic insulinoma suffered from frequent hypoglycemic events. Continuous glucose monitoring (CGM) confirmed severe and frequent symptomatic/asymptomatic hypoglycemia. After the initiation of everolimus treatment, the hypoglycemic events were rapidly eliminated. CGM revealed that her blood glucose levels were maintained without hypoglycemia throughout the day. Furthermore, everolimus reduced the duration of time above the upper limit (>180 mg/dL) along with the standard deviation and mean amplitude of glycemic excursions. This case shows the potential effects of everolimus on hypoglycemia and glycemic control in a patient with inoperable metastatic insulinoma evaluated by CGM.

Everolimus Directly Suppresses Insulin Secretion Independently of Cell Growth Inhibition

Everolimus, an orally administered mammalian target of rapamycin inhibitor, has been widely used as an immunosuppressant and an anticancer agent. Whereas everolimus can control recurrent hypoglycemia in patients with insulinoma, possibly through tumor regression and/or the direct inhibition of insulin secretion, time-dependent changes in serum insulin levels caused by everolimus still remain unclear. Here we report a clinical case of a patient with metastatic insulinoma, in which frequent monitoring of serum insulin levels demonstrated rapid and substantial changes in insulin secretion levels, a few days after the discontinuation as well as the readministration of everolimus. To further confirm the direct effect of everolimus on β-cell function, we performed in vitro experiments using mouse insulinoma cells (MIN6) and human induced pluripotent stem cell (hiPSC)–derived insulin-producing cells and found that everolimus significantly suppressed glucose-stimulated insulin secretion in both MIN6 cells and hiPSC–derived insulin-producing cells. Thus, both a patient with metastatic insulinoma and in vitro experiments demonstrated that everolimus directly suppresses insulin secretion, independently of its tumor regression effect.

Multidisciplinary management of refractory insulinomas

Insulinomas are predominantly benign (~90%), pancreatic neuroendocrine tumours characterized by hyperinsulinaemic hypoglycaemia. They usually present as a small (<2 cm), well-demarcated, solitary nodule that can arise in any part of the organ. Treatment for sporadic insulinomas is generally aimed at curative surgical resection with special consideration in genetic syndromes. Patients with significant hypoglycaemia can pose a difficult management challenge. In isolated cases where the patient is not medically fit for surgery or with metastatic spread, other treatment options are employed. Medical therapy with diazoxide or somatostatin analogues is commonly used first line for symptom control, albeit with variable efficacy. Other medical options are emerging, including newer targeted biological therapies, including everolimus (an mTOR inhibitor), sunitinib (a tyrosine kinase inhibitor) and pasireotide, a multisomatostatin receptor ligand. Pasireotide and everolimus both cause hyperglycaemia by physiological mechanisms synergistic with its antitumour/antiproliferative effects. Minimally invasive treatment modalities such as ethanol ablation are available in selected cases (particularly in patients unfit for surgery), peptide receptor radionuclide therapy (PRRT) can effectively control tumour growth or provide symptomatic benefit in metastatic disease, while cytotoxic chemotherapy can be used in patients with higher-grade tumours. This review considers the developments in the medical and other nonsurgical management options for cases refractory to standard medical management. Early referral to a dedicated neuroendocrine multidisciplinary team is critical considering the array of medical, oncological, interventional radiological and nuclear medical options. We discuss the evolving armamentarium for insulinomas when standard medical therapy fails.

[High grade insulinoma detected in a patient with a 5-year history of severe hypoglycemias]

Les tumeurs endocrines fonctionnelles du pancréas sont des lésions rares, parmi lesquelles les insulinomes sont les plus fréquents. La majorité des patients atteints d'insulinome ont entre 30 et 60 ans et 59% d'entre eux sont des femmes. La plupart des insulinomes sont sporadiques, alors que 10% sont développés chez des patients atteints de NEM. Le diagnostic repose sur la clinique et sur le bilan biologique. Le bilan d'imagerie préopératoire (Echo-endoscopie, TDM, IRM) est essentiel localisant la tumeur dans plus de 80% des cas. Le traitement de référence est l'exérèse chirurgicale de la tumeur. Nous rapportons ici un cas d'insulinome de haut grade développé sur la face antérieure de la queue du pancréas chez une patiente de 50 ans.

Adult-onset hyperinsulinaemic hypoglycaemia in clinical practice: diagnosis, aetiology and management

OBJECTIVE

In adults with hyperinsulinaemic hypoglycaemia (HH), in particular those with insulinoma, the optimal diagnostic and management strategies remain uncertain. Here, we sought to characterise the biochemical and radiological assessment, and clinical management of adults with HH at a tertiary centre over a thirteen-year period.

DESIGN

Clinical, biochemical, radiological and histological data were reviewed from all confirmed cases of adult-onset hyperinsulinaemic hypoglycaemia at our centre between 2003 and 2016. In a subset of patients with stage I insulinoma, whole-exome sequencing of tumour DNA was performed.

RESULTS

Twenty-nine patients were identified (27 insulinoma, including 6 subjects with metastatic disease; 1 pro-insulin/GLP-1 co-secreting tumour; 1 activating glucokinase mutation). In all cases, hypoglycaemia (glucose ≤2.2 mmol/L) was achieved within 48 h of a supervised fast. At fast termination, subjects with stage IV insulinoma had significantly higher insulin, C-peptide and pro-insulin compared to those with insulinoma staged I-IIIB. Preoperative localisation of insulinoma was most successfully achieved with EUS. In two patients with inoperable, metastatic insulinoma, peptide receptor radionuclide therapy (PRRT) with ¹⁷⁷Lu-DOTATATE rapidly restored euglycaemia and lowered fasting insulin. Finally, in a subset of stage I insulinoma, whole-exome sequencing of tumour DNA identified the pathogenic Ying Yang-1 (YY1) somatic mutation (c.C1115G/p.T372R) in one tumour, with all tumours exhibiting a low somatic mutation burden.

CONCLUSION

Our study highlights, in particular, the utility of the 48-h fast in the diagnosis of insulinoma, EUS for tumour localisation and the value of PRRT therapy in the treatment of metastatic disease.

Everolimus Effect on Gastrin and Glucagon in Pancreatic Neuroendocrine Tumors

OBJECTIVES

The pharmacodynamic effects of everolimus on gastrointestinal hormone levels have not been described in patients with pancreatic neuroendocrine tumors (pNETs). We report the effects of everolimus on gastrin and glucagon levels in patients with progressive pNET in RADIANT-1 (a single-arm phase II trial) and RADIANT-3 (a placebo-controlled, randomized, phase III trial).

METHODS

Serum gastrin and glucagon levels were determined by immunoassay at baseline and at predose in subsequent treatment cycles in patients with elevated baseline hormone levels. The analyses included 158 patients from RADIANT-1 and 404 patients from RADIANT-3.

RESULTS

In RADIANT-1, everolimus induced a rapid, sustained decrease in median gastrin and glucagon levels to approximately 60% and 70% of baseline levels, respectively. In RADIANT-3, everolimus consistently reduced median gastrin and glucagon levels by greater than 50% and approximately 40%, respectively (everolimus vs placebo, P < 0.0001), whereas with placebo, both hormones at each time point were essentially the same as their baseline levels. In patients with concomitant octreotide long-acting repeatable treatment, the moderate pharmacodynamic effect on lowering gastrin was greater than that seen with everolimus alone.

CONCLUSIONS

In addition to prolonging progression-free survival in patients with pNET, everolimus down-regulates excess production of 2 gastrointestinal hormones, which may help control their associated clinical syndromes.

The treatment of hyperinsulinemic hypoglycaemia in adults: an update

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Treatment of symptomatic neuroendocrine tumor syndromes: recent advances and controversies

INTRODUCTION

Neuroendocrine tumors(NETs), once thought rare, are increasing in frequency in most countries and receiving increasing-attention. NETs present two-treatment problems. A proportion is aggressive and a proportion has a functional, hormone-excess-state(F-NET), each of which must be treated. Recently, there have been many advances, well-covered in reviews/consensus papers on imaging-NETs; new, novel anti-tumor treatments and understanding their pathogenesis. However, little attention has been paid to advances in the treatment of the hormone-excess-state. These advances are usually reported in case-series, and case-reports with few large studies. In this paper these advances are reviewed. Areas covered: Advances in the last 5-years are concentrated on, but a review of literature from the last 10-years was performed. PubMed and other databases (Cochrane, etc.) were searched for F-NET-syndromes including carcinoid-syndrome, as well as meeting-abstracts on NETs. All advances that controlled hormone-excess-states or facilitated-control were covered. These include new medical-therapies [serotonin-synthesis inhibitors(telotristat), Pasireotide, new agents for treating ACTHomas], increased dosing with conventional therapies (octreotide-LAR, Lanreotide-Autogel), mTor inhibitors(everolimus), Tyrosine-kinase inhibitors(sunitinib),cytoreductive surgery, liver-directed therapies (embolization, chemoembolization, radioembolization, RFA), peptide radio-receptor-therapy(PRRT) and ¹³¹I-MIBG, ablation of primary F-NETs. Expert opinion: Although many of the newer therapies controlling the hormone-excess-states in F-NETs are reported in relatively few patients, all the approaches show promise. Their description also generates some controversies/unresolved areas,such as the order of these new treatments, their longterm-efficacy, and effectiveness of combinations which may require large,controlled studies.

Prolonged life-threatening hypoglycaemia following dose escalation of octreotide LAR in a patient with malignant polysecreting pancreatic neuroendocrine tumour

This paper details the case of a 77-year-old male with refractory hypoglycaemia due to inoperable metastatic pancreatic neuroendocrine tumour (pNET) co-secreting insulin and gastrin. Multiple medical therapies were trialled with limited success, and we describe the complications experienced by our patient. Somatostatin analogues can ameliorate hypoglycaemia and may have tumour-stabilising effects; however, in our case resulted in paradoxical worsening of hypoglycaemia. This rendered our patient hospital dependent for glycaemic support including continuous dextrose infusion. Although this is a reported adverse effect with initiation of therapy, we describe successful initiation of short-acting octreotide as an inpatient followed by commencement of long-acting octreotide. Hypoglycaemic collapse occurred only after dose titration of long-acting octreotide. We outline the pitfalls of somatostatin analogue therapy and the mechanisms that may contribute to worsening hypoglycaemia. This rare side effect cannot be reliably predicted, necessitating close supervision and glucose monitoring during therapy. Our patient achieved disease stabilisation and gradual resolution of hypoglycaemia with peptide receptor radionuclide therapy (PRRT), an emerging therapeutic option for metastatic neuroendocrine tumours with high efficacy and low toxicity. We present a brief but comprehensive discussion of currently available and novel therapies for insulin secreting pNETs.

Liver transplantation for metastatic neuroendocrine tumors

The ideal management of NET must be addressed on a case-by-case basis, with consideration given to patient factors, disease burden, and clinical tumor activity. Outcome improvement for LT in the setting of metastatic disease requires better characterization of the biological behavior of NETs and further identification of factors to be included in the selection criteria. Box 3 summarizes the many areas that have been, and are currently, undergoing investigation. LT as an attempt for cure rather than palliation is a justified treatment option for well-selected patients with metastatic neuroendocrine tumors of the pancreas and GI system. Optimization of pretransplantation staging and patient management algorithms, patient selection, and posttransplant management options are areas that need to be better defined. Further investigations for defining reproducible prognostic factors, consistent histopathologic evaluation, and uniform preoperative staging and site-specific data are needed. With the advancement of newer treatment modalities, it is necessary to define the role of LT along with the optimal perioperative management of existing and recurrent disease.

[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.

Everolimus dramatically improves glycemic control in unresectable metastatic insulinoma: a case report

Hypoglycemia poses a significant management challenge in patients with unresectable metastatic insulinoma. A 57-year-old woman with pancreatic neuroendocrine tumor with multiple liver metastases was referred to our institution. During the clinical course of pancreatic neuroendocrine tumor, she had experienced palpitations, cold sweats and faintness between meals that indicated her tumors had attained the characteristics of an insulinoma, and her quality of life was impacted by frequent hypoglycemic episodes which could not be prevented by conventional therapies. Shortly after the approval of everolimus for pancreatic neuroendocrine tumor in Japan, we began oral administration at 10 mg per day, which produced a rapid and substantial improvement in glycemic control. The serum insulin level decreased dramatically despite the tumor size remaining stable on computed tomography evaluation. Despite a dose reduction of everolimus to 5 mg per day in response to the adverse reaction of interstitial pneumonitis and a subsequent moderate increase in the serum insulin level, the patient has maintained normoglycemia for a year. Everolimus might represent the treatment of choice for unresectable insulinoma in terms of not only tumor stabilization but also glycemic control.

Targeted therapy with kinase inhibitors in aggressive endocrine tumors

INTRODUCTION

Kinase inhibitors (KIs) are a class of anticancer drugs that inhibit activity of the enzymes protein kinases, which regulate crucial cellular processes and have a demonstrated role in human oncogenesis. Treatment of advanced forms of endocrine cancer which are not responsive to cytotoxic chemotherapies is challenging and use of KIs is gaining a growing role in this field.

AREAS COVERED

The authors summarize the main genetic alterations known to be linked to endocrine tumors, indicating the rationale for utilizing KIs. Furthermore, they present an updated analysis of clinical trials available on PubMed Central, which were pertinent to the activities of KIs in aggressive endocrine cancer. The authors also discuss the adverse effects of KIs and summarize likely involved underlying mechanisms.

EXPERT OPINION

KIs are effective in obtaining a radiological disease control and an improvement of progression-free survival in several forms of endocrine cancer but will never deliver a knockout blow of the disease, due to mechanisms of adaptation to circumvent the specific molecular blockade. The new frontier of KIs treatment is to identify agents that could synergize activity of KIs. The true goal will be to perform an overall genotyping of each tumor, thus predicting the impact of combined targeted therapies in the context of a particular constellation of mutant genes.

The use of targeted therapies in pancreatic neuroendocrine tumours: patient assessment, treatment administration, and management of adverse events

Together with the use of novel oral targeted therapies, a multidisciplinary approach can be used to effectively treat patients with advanced pancreatic neuroendocrine tumours (pNETs). Here we review the integration of the oncology nurse to the newly developed oral treatment setting for patients with pNETs. From the outset, the nurse must be involved in various processes, including performance of baseline assessments (e.g. blood pathology, cardiac and lung function testing, patient history) and general medical observations, treatment administration, dietary guidance, evaluation of comorbidities, and review of concomitant medications. Patient education and establishment of a strong partnership in care before the start of pNET therapy ultimately increase treatment adherence and reduce potential toxicities. Regular review of general patient status and disease progression and continuous monitoring of adverse events also help enhance treatment outcomes and subsequently improve quality of life. Nurses' knowledge of agent-specific toxicities and prompt, proactive management is a critical aspect of care. In essence, as the pNET treatment landscape evolves, the role of the healthcare professional in overall patient care must shift accordingly.

Efficacy of everolimus in patients with metastatic insulinoma and refractory hypoglycemia

BACKGROUND

Refractory hypoglycemia in patients with metastatic insulinoma is an important cause of morbidity and mortality. Everolimus could be a new therapeutic option.

METHODS

Within the French Group, we conducted a retrospective, multicentric study of endocrine tumors to evaluate the time to the first recurrence of symptomatic hypoglycemia, after everolimus initiation, in patients with metastatic insulinoma and refractory hypoglycemia. Ongoing hyperglycemic medical options, tumor response, and safety information were recorded.

RESULTS

Twelve patients with metastatic insulinoma and refractory hypoglycemia who were treated with everolimus between May 2007 and June 2011 were reviewed. Everolimus (starting dose, 10 mg/day, except in one patient, 5 mg/day) was given after a median of four previous therapeutic lines. Medication aimed at normalizing blood glucose levels in 11 patients. After a median duration of 6.5 months (range 1-35+ months), median time to the first recurrence of symptomatic hypoglycemia was 6.5 months (range 0 to 35+ months). Three patients discontinued everolimus because of cardiac and/or pulmonary adverse events at 1, 1.5, and 7 months after initiation, which led to two deaths. Three patients discontinued everolimus because of tumor progression at 2, 3, and 10 months after initiation, without recurrence of hypoglycemia.

CONCLUSION

Everolimus appears to be a new effective treatment for patients with metastatic insulinoma and refractory hypoglycemia. Tolerance should be carefully monitored.

Management of malignant insulinoma

AIM

Malignant insulinoma is an infrequent functional endocrine tumor of the pancreas. Adequate therapy is a demanding challenge for oncologists and endocrinologists.

OBJECTIVE

To evaluate the results of multidisciplinary management of malignant insulinoma.

MATERIALS AND METHODS

Retrospective review of patients with malignant insulinoma treated from 1995 to 2011.

RESULTS

Seven patients with malignant insulinoma were included: four males and three females; median age was 61.8 years (range 37-78). Six tumors were sporadic and one was diagnosed in a patient with a type 1 multiple endocrine neoplasia (MEN-1). Surgery was performed in six cases and one patient was considered unresectable. Hypoglycemias persisted in all cases and somatostatin analogs, glucocorticoids and diazoxide were used. Two patients received everolimus. Other techniques were chemoembolization and internal radiation therapy with yttrium-90. Successful liver transplant was done in the patient with MEN-1.

CONCLUSION

Hypoglycemia management is complex and requires multiple therapies. Further evaluations will be necessary to determine the best treatment.

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.

Therapy of metastatic pancreatic neuroendocrine tumors (pNETs): recent insights and advances

Neuroendocrine tumors (NETs) [carcinoids, pancreatic neuroendocrine tumors (pNETs)] are becoming an increasing clinical problem because not only are they increasing in frequency, but they can frequently present with advanced disease that requires diagnostic and treatment approaches different from those used in the neoplasms that most physicians are used to seeing and treating. In the past few years there have been numerous advances in all aspects of NETs including: an understanding of their unique pathogenesis; specific classification systems developed which have prognostic value; novel methods of tumor localization developed; and novel treatment approaches described. In patients with advanced metastatic disease these include the use of newer chemotherapeutic approaches, an increased understanding of the role of surgery and cytoreductive methods, the development of methods for targeted delivery of cytotoxic agents, and the development of targeted medical therapies (everolimus, sunitinib) based on an increased understanding of the disease biology. Although pNETs and gastrointestinal NETs share many features, recent studies show they differ in pathogenesis and in many aspects of diagnosis and treatment, including their responsiveness to different therapies. Because of limited space, this review will be limited to the advances made in the management and treatment of patients with advanced metastatic pNETs over the past 5 years.

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.

Everolimus resolving hypoglycemia, producing hyperglycemia, and necessitating insulin use in a patient with diabetes and nonresectable malignant insulinoma

OBJECTIVE

To present a case of management of refractory hypoglycemia due to malignant insulinoma with use of everolimus, resulting in recurrent insulin-requiring diabetes.

METHODS

This report describes a case of a nonresectable malignant insulinoma in a 78-year-old patient with long-standing type 2 diabetes mellitus. Endogenous hyperinsulinism was confirmed by a fasting test, which revealed a glucose level of 35 mg/dL and an insulin value of 23.7 μIU/mL. Endoscopic ultrasonography, magnetic resonance imaging, and computed tomography identified a pancreatic mass, infiltration of the superior mesenteric vein, and metastatic lesions in the liver.

RESULTS

After chemoembolization of the metastatic lesions, hypoglycemia recurred, despite combined treatment with somatostatin analogues, dexamethasone, and diazoxide. Everolimus, an orally administered mammalian target of rapamycin, was used at a daily dose of 5 mg. After 6 months, the hypoglycemia was controlled, and the patient presented with a C-peptide level of 0.2 ng/mL and secondary hyperglycemia that necessitated insulin treatment.

CONCLUSION

The orally administered drug everolimus controlled hypoglycemia due to a malignant insulinoma in a patient with prior insulin-requiring diabetes. Secondary hyperglycemia was an acceptable drug effect (to the patient and managing physicians), in light of the complex and often poorly tolerated treatments available for this rare condition.

[Malignant insulinoma]

Authors present the history of a 56-year-old man who was evaluated for recurrent epigastric pain. Clinical investigation revealed a 4-cm tumor in the head of the pancreas and a solitary liver metastasis. Pathological examination of the surgically excised pancreatic tumor indicated a moderately differentiated neuroendocrine carcinoma and Ki-67 labeling index revealed moderate proliferative activity. Despite short-term chemotherapy combined with interferon and somatostatin analogue administration, the metastatic disease rapidly progressed. Octreotide scintigraphy disclosed abundant expression of somatostatin receptors both on primary tumor and hepatic metastases. ⁹⁰Yttrium-DOTATOC treatment was performed in three sessions within 9 months (3 x 200 mCi) with a mixed therapeutic response. Endocrine symptoms were not observed during the first 33 months of the disease. 34 months after the initial diagnosis of the neoplastic disease, imaging studies and chromogranin A measurement revealed rapidly progressing disease and the patient developed frequent episodes of hypoglycemic attacks. Serum insulin and C-peptide measurements confirmed insulin oversecretion. Continuous administration of somatostatin analogue was supplemented with diazoxide, but the latter therapy was not tolerated because of severe water retention. The high dose oral carbohydrate intake was supplemented with continuous glucose infusion. As a rescue procedure, repeated liver chemoembolization was performed, which resulted only in a short-term effect. The autopsy and the immunohistochemical investigations confirmed the diagnosis of insulin-producing, metastatic neuroendocrine carcinoma.

Metastatic insulinoma in a patient with type 2 diabetes mellitus: case report and review of the literature

Pancreatic neuroendocrine tumors (NETs) are extremely rare, and although insulinomas are the commonest, less than 10% of insulinomas are malignant. Most patients with insulinomas present with neuroglycopenic symptoms and weight gain attributable to insulin excess. Here, we report a case where a 67-year-old lady with a background history of type 2 diabetes mellitus and breakthrough hyperinsulinism who presented with coma. The biochemical profile revealed features typical of insulinoma, and CT and endosonography confirmed a pancreatic tumor with large volume right-sided liver metastases (biopsy confirming a neuroendocrine tumor). The patient underwent successful one-step RO surgical resection, distal pancreatectomy, splenectomy, and right hepatectomy, and 9 months postoperatively, she remains free of recurrent disease. She remains a diabetic.

NANETS treatment guidelines: well-differentiated neuroendocrine tumors of the stomach and pancreas

Well-differentiated neuroendocrine tumors (NETs) of the stomach and pancreas represent 2 major subtypes of gastrointestinal NETs. Historically, there has been little consensus on the classification and management of patients with these tumor subtypes. We provide an overview of well-differentiated NETs of the stomach and pancreas and describe consensus guidelines for the treatment of patients with these malignancies.