Surgery and Radiofrequency Ablation for Treatment of Liver Metastases from Midgut and Foregut Carcinoids and Endocrine Pancreatic Tumors

Characteristics and treatment options of glucagonomas: a national study from the French Group of Endocrine Tumors and ENDOCAN-RENATEN network

OBJECTIVE

Glucagonoma is a very rare functional pancreatic neuroendocrine tumor (PanNET). We aimed to provide data on the diagnosis, prognosis, and management of patients with glucagonoma.

DESIGN AND METHODS

In this retrospective national cohort, we included all patients with glucagonoma, defined by at least 1 major criterion (necrolytic migratory erythema [NME] and/or recent-onset diabetes, and/or weight loss ≥ 5 kg) associated with either glucagonemia > 2 × upper limit of normal or positive glucagon immunostaining. Antisecretory efficacy was defined as partial/complete resolution of glucagonoma symptoms. Antitumor efficacy was assessed according to the time to next treatment (TTNT).

RESULTS

Thirty-eight patients were included with median age 58.7 yo, primary PanNET located in the tail (68.4%), synchronous metastases (63.2%). Median Ki-67 index was 3%. Most frequent glucagonoma symptoms at diagnosis were NME (86.8%), weight loss (68.4%), and diabetes (50%). Surgery of the primary PanNET was performed in 76.3% of cases, mainly with curative intent (61.5%). After surgery, complete resolution of NME was seen in 93.8% (n = 15/16). The secretory response rates were 85.7%, 85.7%, 75%, and 60% with surgery of metastases (n = 6/7), chemotherapy (n = 6/7), liver-directed therapy (n = 6/8), and somatostatin analogs (n = 6/10), respectively. All lines combined, longer TTNT was reported with chemotherapy (20.2 months). Median overall survival (OS) was 17.3 years. The Ki-67 index > 3% was associated with shorter OS (hazard ratio 5.27, 95% CI [1.11-24.96], P = .036).

CONCLUSION

Patients with glucagonoma had prolonged survival, even in the presence of metastases at diagnosis. Curative-intent surgery should always be considered. Chemotherapy, peptide receptor radionuclide therapy, or liver-directed therapy seems to provide both substantial antitumor and antisecretory efficacies.

Image-Guided Precision Medicine in the Diagnosis and Treatment of Pheochromocytomas and Paragangliomas

In this comprehensive review, we aimed to discuss the current state-of-the-art medical imaging for pheochromocytomas and paragangliomas (PPGLs) diagnosis and treatment. Despite major medical improvements, PPGLs, as with other neuroendocrine tumors (NETs), leave clinicians facing several challenges; their inherent particularities and their diagnosis and treatment pose several challenges for clinicians due to their inherent complexity, and they require management by multidisciplinary teams. The conventional concepts of medical imaging are currently undergoing a paradigm shift, thanks to developments in radiomic and metabolic imaging. However, despite active research, clinical relevance of these new parameters remains unclear, and further multicentric studies are needed in order to validate and increase widespread use and integration in clinical routine. Use of AI in PPGLs may detect changes in tumor phenotype that precede classical medical imaging biomarkers, such as shape, texture, and size. Since PPGLs are rare, slow-growing, and heterogeneous, multicentric collaboration will be necessary to have enough data in order to develop new PPGL biomarkers. In this nonsystematic review, our aim is to present an exhaustive pedagogical tool based on real-world cases, dedicated to physicians dealing with PPGLs, augmented by perspectives of artificial intelligence and big data.

European Neuroendocrine Tumor Society 2023 guidance paper for functioning pancreatic neuroendocrine tumour syndromes

This ENETS guidance paper aims to provide practical advice to clinicians for the diagnosis, treatment and follow-up of functioning syndromes in pancreatic neuroendocrine tumours (NET). A NET-associated functioning syndrome is defined by the presence of a clinical syndrome combined with biochemical evidence of inappropriately elevated hormonal levels. Different hormonal syndromes can be encountered in pancreatic NET patients, including insulinoma, gastrinoma as well as the rare glucagonoma, VIPoma, ACTHoma, PTHrPoma, carcinoid syndrome, calcitoninoma, GHRHoma and somatostatinoma. The recommendations provided in this paper focus on the biochemical, genetic and imaging work-up as well as therapeutic management of the individual hormonal syndromes in well-differentiated, grade 1-3, functioning NET with the primary tumour originating in the pancreas, and for specific subtypes also in the duodenum.

Neuroendocrine Tumors: Genomics and Molecular Biomarkers with a Focus on Metastatic Disease

Neuroendocrine tumors (NETs) are considered rare tumors that originate from specialized endocrine cells. Patients often present with metastatic disease at the time of diagnosis, which negatively impacts their quality of life and overall survival. An understanding of the genetic mutations that drive these tumors and the biomarkers used to detect new NET cases is important to identify patients at an earlier disease stage. Elevations in CgA, synaptophysin, and 5-HIAA are most commonly used to identify NETs and assess prognosis; however, new advances in whole genome sequencing and multigenomic blood assays have allowed for a greater understanding of the drivers of NETs and more sensitive and specific tests to diagnose tumors and assess disease response. Treating NET liver metastases is important in managing hormonal or carcinoid symptoms and is imperative to improve patient survival. Treatment for liver-dominant disease is varied; delineating biomarkers that may predict response will allow for better patient stratification.

Therapeutic strategies for gastroenteropancreatic neuroendocrine neoplasms: State-of-the-art and future perspectives

Although gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have always been considered rare tumors, their incidence has risen over the past few decades. They represent a highly heterogeneous group of neoplasms with several prognostic factors, including disease stage, proliferative index (Ki67), and tumor differentiation. Most of these neoplasms express somatostatin receptors on the cell surface, a feature that has important implications in terms of prognosis, diagnosis, and therapy. Although International Guidelines propose algorithms aimed at guiding therapeutic strategies, GEP-NEN patients are still very different from one another, and the need for personalized treatment continues to increase. Radical surgery is always the best option when feasible; however, up to 80% of cases are metastatic upon diagnosis. Regarding medical treatments, as GEP-NENs are characterized by relatively long overall survival, multiple therapy lines are adopted during the lifetime of these patients, but the optimum sequence to be followed has never been clearly defined. Furthermore, although new molecular markers aimed at predicting the response to therapy, as well as prognostic scores, are currently being studied, their application is still far from being part of daily clinical practice. As they represent a complex disease, with therapeutic protocols that are not completely standardized, GEP-NENs require a multidisciplinary approach. This review will provide an overview of the available therapeutic options for GEP-NENs and attempts to clarify the possible approaches for the management of these patients and to discuss future perspectives in this field.

Update in carcinoid heart disease - the heart of the matter

Carcinoid heart disease (CHD) is a paraneoplastic cardiac manifestation occurring in patients with carcinoid syndrome (CS) and advanced neuroendocrine malignancy. In about 20-40% of patients with CS, chronic exposure to tumor-released circulating vasoactive peptides typically results in right-sided valvular fibrosis leading to valve dysfunction and right heart failure. CHD remains a significant cause of morbidity and mortality. The management of patients with CHD is complex, as both the systemic malignant disease and the heart involvement have to be addressed. Early diagnosis and timely surgical intervention in selected patients are of utmost importance and offer a survival benefit. In patients with advanced carcinoid heart disease, valve replacement surgery is the most effective option to alleviate cardiac symptoms and contribute to survival outcomes. A collaboration of a multidisciplinary team in centers with experience is required to provide optimal patient management. Here, we review the current literature regarding CHD presentation, pathophysiology, diagnostic tools, and available treatment strategies.

Nordic guidelines 2021 for diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms

BACKGROUND

The diagnostic work-up and treatment of patients with gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN) has undergone major advances and new methods are introduced. Furthermore, an update of the WHO classification has resulted in a new nomenclature for GEP-NEN that is implemented in the clinic.

AIM

These Nordic guidelines summarise the Nordic Neuroendocrine Tumour Group's current view on how to diagnose and treat GEP-NEN patients and aims to be useful in the daily practice for clinicians.

Comparative safety review of the current therapies for gastroenteropancreatic neuroendocrine tumors

Introduction: Neuroendocrine neoplasms (NENs) comprise a heterogeneous group of neoplasms, whose management requires complex and individualized clinical decisions. Over the last decades the advent of novel medications and advanced diagnostic and therapeutic modalities, alongside our deeper understanding of the disease, revolutionized the landscape of their management, significantly improving both prognosis and quality of life of patients.Area covered: Treatment-related adverse events and safety concerns as demonstrated in clinical trials, as well as in real-world clinical practice.Expert opinion: The only true curative option for NENs remains surgery, whereas high-grade advanced neuroendocrine carcinomas should be primarily managed with platinum-based chemotherapy. For the remaining cases, that comprise the vast majority, the current armamentarium includes somatostatin analogs, interferon, telotristat ethyl, molecular targeted therapies, chemotherapy, peptide receptor radionuclide therapy, and locoregional treatment. The use of the aforementioned therapeutic options is associated with several and not uncommonly severe treatment-related adverse events. However, the benefits offered inclusive of improved prognosis, amelioration of symptoms, and better quality of life amidst others, by far outweighs any adverse event.

Long-term survival of two patients with recurrent pancreatic acinar cell carcinoma treated with radiofrequency ablation: A case report

BACKGROUND

Pancreatic acinar cell carcinoma (PACC) is a rare type of malignant pancreatic cancer that represents approximately 1% of all pancreatic neoplasms. Due to its very low incidence, only a few retrospective studies are available. Although surgery is the first choice for treatment, most patients experience recurrence (mainly in the liver) and there are no clear recommendations for patients with advanced disease.

CASE SUMMARY

We report two patients with PACC treated with surgery who experienced tumour recurrence in the liver. Patient 1 carried a germline mutation in the APC gene. Both patients were treated with gemcitabine plus oxaliplatin and gemcitabine plus capecitabine as first- and second-line therapies, respectively. After a favourable response to chemotherapy, the patients underwent radiofrequency ablation of the remaining liver metastases. For patient 1, we documented a relapse in the liver after a disease-free period of 9 mo, and treatment with gemcitabine plus capecitabine was restarted. The patient achieved a complete response, and he remains alive without evidence of disease recurrence after six years. After radiofrequency ablation, patient 2 experienced disease-free survival for 21 mo, when peritoneal relapse was diagnosed and treated with chemotherapy. The patient achieved a stable disease state for nearly two years; nevertheless, further progressive disease was documented, and he died seven years after the first relapse.

CONCLUSION

PACC presents different biological behaviours than pancreatic adenocarcinoma. Multidisciplinary treatment involving local ablative therapies may be considered for PACC.

Carcinoid Syndrome: A Review

Carcinoid syndrome (CS) is a paraneoplastic syndrome caused by the release of serotonin and other substances from well-differentiated neuroendocrine tumors (NETs). The hallmark symptoms of carcinoid syndrome are flushing and diarrhea; atypical signs and symptoms can include wheezing, abdominal pain, valvular heart disease, telangiectasias, pellagra, and the complications of mesenteric fibrosis, including ureteral obstruction, bowel obstruction, and bowel ischemia. These symptoms are mediated by the release of serotonin (5-HT), histamine, kallikrein, prostaglandins, and tachykinins. The diagnosis of CS requires these symptoms and corresponding elevations in lab tests. Treatment options include surgery and medical management with somatostatin analogs.

Carcinoid Syndrome: Updates and Review of Current Therapy

OPINION STATEMENT

Carcinoid syndrome (CS) is a complex disorder caused by functional neuroendocrine tumors (NETs). This debilitating disease is characterized by hyper-secretion of biologically active substances eliciting major hormonal symptoms burden and fibrotic changes that are often challenging for management. There have been a number of insights that have substantially advanced treatments since the introduction of somatostatin analogs (SSAs). Second-line treatments are needed in a substantial proportion of patients with advanced disease that have uncontrolled hormone secretion on the highest labeled doses of SSAs. International guidelines suggest several available options including dose escalation of SSAs, interferon alpha, everolimus, radionuclide therapy, liver-directed therapies, and the novel tryptophan hydroxylase 1 inhibitor, telotristat ethyl. The clear preference of one second-line therapy over the other is not stated since their relative and long-term efficacy are largely unknown, and standardized approach of hormonal response assessment is lacking in the literature. In the clinical setting, the treatment of CS is guided in conjunction with patients' performance status, tumor origin, grade, stage, and growth rate, with regard to both anti-hormonal, as well as anti-proliferative effect. There is an unmet need for further well-designed randomized placebo-controlled and head-to-head studies that systematically assess CS symptom control and biochemical response following a specific intervention.

The role of multimodal imaging in guiding resectability and cytoreduction in pancreatic neuroendocrine tumors: focus on PET and MRI

Pancreatic neuroendocrine tumors (pNETs) are rare neoplasms that secrete peptides and neuro-amines. pNETs can be sporadic or hereditary, syndromic or non-syndromic with different clinical presentations and prognoses. The role of medical imaging includes locating the tumor, assessing its extent, and evaluating the feasibility of curative surgery or cytoreduction. Pancreatic NETs have very distinctive phenotypes on CT, MRI, and PET. PET have been demonstrated to be very sensitive to detect either well-differentiated pNETs using ⁶⁸Gallium somatostatin receptor (SSTR) radiotracers, or more aggressive undifferentiated pNETS using ¹⁸F-FDG. A comprehensive interpretation of multimodal imaging guides resectability and cytoreduction in pNETs. The imaging phenotype provides information on the differentiation and proliferation of pNETs, as well as the spatial and temporal heterogeneity of tumors with prognostic and therapeutic implications. This review provides a structured approach for standardized reading and reporting of medical imaging studies with a focus on PET and MR techniques. It explains which imaging approach should be used for different subtypes of pNET and what a radiologist should be looking for and reporting when interpreting these studies.

New Treatments for the Carcinoid Syndrome

Neuroendocrine tumors, including carcinoids, are rare and insidiously growing tumors. Related to their site of origin, tumors can be functional, causing various forms of the carcinoid syndrome, owing to the overproduction of serotonin, histamine, or other bioactive substances. They often invade adjacent structures or metastasize to the liver and elsewhere. Treatment includes multimodal approaches, including cytoreductive surgery, locoregional embolization, cytotoxic therapy, peptide receptor radionuclide therapy, and various targeted therapies with goals of symptom relief and control of tumor growth. This article summarizes current and emerging approaches to management and reviews several promising future therapies.

Treatment options for PNET liver metastases: a systematic review

BACKGROUND

Pancreatic neuroendocrine tumors (PNETs) are rare pancreatic neoplasms. About 40-80% of patients with PNET are metastatic at presentation, usually involving the liver (40-93%). Liver metastasis represents the most significant prognostic factor. The aim of this study is to present an up-to-date review of treatment options for patients with liver metastases from PNETs.

METHODS

A systematic literature search was performed using the PubMed database to identify all pertinent studies published up to May 2018.

RESULTS

The literature search evaluated all the therapeutic options for patients with liver metastases of PNETs, including surgical treatment, loco-regional therapies, and pharmacological treatment. All the different treatment options showed particular indications in different presentations of liver metastases of PNET. Surgery remains the only potentially curative therapeutic option in patients with PNETs and resectable liver metastases, even if relapse rates are high. Efficacy of medical treatment has increased with advances in targeted therapies, such as everolimus and sunitinib, and the introduction of radiolabeled somatostatin analogs. Several techniques for loco-regional control of metastases are available, including chemo- or radioembolization.

CONCLUSIONS

Treatment of patients with PNET metastases should be multidisciplinary and must be personalized according to the features of individual patients and tumors.

Prognostic factors for death after surgery for small intestinal neuroendocrine tumours

Background

Neuroendocrine tumours of the small intestine (SI-NETs) are rare gastrointestinal neoplasms with an annual incidence of about one per 100 000. Patients with apparently similar tumours have variable outcomes. The aim of this study was to identify postoperative prognostic factors identifiable after initial surgery.

Methods

This was a nested case-control study of patients with SI-NETs who were treated between 1961 and 2001. Data were retrieved from the Swedish Cancer Registry. Patients who died from the SI-NET and corresponding controls (who outlived cases by at least 1 month), matched by age at diagnosis and calendar period, were included. Sex, postoperative symptoms, postoperative 5-hydroxyindoleacetic acid (5-HIAA) values, European Neuroendocrine Tumor Society (ENETS) stage, insufficiency of the tricuspid valve, radical secondary surgery and secondary malignancy were studied as potential prognostic factors.

Results

In total, 1122 patients were included (561 cases, 561 controls). Postoperative factors of prognostic importance included hormone-related symptoms, stage IV disease, raised levels of 5-HIAA, insufficiency of the tricuspid valve, secondary surgery not being macroscopically radical and a second malignancy.

Conclusion

Stage and symptomatic disease are important prognostic factors in SI-NET.

NKX2.2, PDX-1 and CDX-2 as potential biomarkers to differentiate well-differentiated neuroendocrine tumors

Background

Well-differentiated neuroendocrine tumors (NET) most frequently arise from the gastrointestinal tract (GI), pancreas, and lung. Patients often present as metastasis with an unknown primary, and the clinical management and outcome depend on multiple factors, including the accurate diagnosis with the tumor primary site. Determining the site of the NET with unknown primary remains challenging. Many biomarkers have been investigated in primary NETs and metastatic NETs, with heterogeneous sensitivity and specificity observed.

Methods

We used high-throughput tissue microarray (TMA) and immunohistochemistry (IHC) with antibodies against a panel of transcriptional factors including NKX2.2, PDX-1, PTF1A, and CDX-2 on archived formalin-fixed paraffin-embedded NETs, and investigated the protein expression pattern of these transcription factors in 109 primary GI (N = 81), pancreatic (N = 17), and lung (N = 11) NETs.

Results

Differential expression pattern of these markers was observed. In the GI and pancreatic NETs (N = 98), NKX2.2, PDX-1, and CDX-2 were immunoreactive in 82 (84%), 14 (14%), and 52 (52%) cases, respectively. PDX-1 was expressed mainly in the small intestinal and appendiceal NETs, occasionally in the pancreatic NETs, and not in the colorectal NETs. All three biomarkers including NKX2.2, PDX-1, and CDX-2 were completely negative in lung NETs. PTF1A was expressed in all normal and neuroendocrine tumor cells.

Conclusions

Our findings suggest that NKX2.2 was a sensitive and specific biomarker for the GI and pancreatic neuroendocrine tumors. We proposed that a panel of immunostains including NKX2.2, PDX-1, and CDX-2 may show diagnostic utility for the most common NETs.

Management of functional neuroendocrine tumors of the pancreas

Pancreatic neuroendocrine tumors (pNETs) constitute a heterogenous group of malignancies with varying clinical presentation, tumor biology and prognosis. The incidence of pNETs has steadily increased during the last decades with an estimated incidence 2012 of 4.8/100,000. Recent whole genome sequencing of pNETs has demonstrated mutations in the DNA repair genes MUTYH and point mutations and gene fusions in four main pathways from chromatin remodeling, DNA damage repair, activation of mechanistic target of rapamycin (mTOR) signaling and the telomere maintenance. This new information will be the foundation for new therapies in the near future for malignant pNETs. The functioning pNETs constitute about 30-40% of all pNETs displaying nine different clinical syndromes: insulinoma, Zollinger-Ellison, Verner-Morrison, glucagonoma, somatostatinomas, ectopic adrenocorticotropic hormone (ACTH) and parathyroid hormone related peptide (PTH-rP) syndromes. Single patients might also present carcinoid syndrome. The diagnostic work-up include histopathology with the new WHO 2017 Classification, biomarkers (CgA, NSE), radiology and molecular imaging including CT-scan, magnetic resonance imaging (MRI), ultrasound and PET-scan. A cornerstone in the treatment of pNETs is surgery which is rarely curative but can reduce the clinical symptoms by debulking which also include radiofrequency ablation, embolization of liver metastases. Medical treatment includes chemotherapy and the targeted agents such as everolimus, sunitinib and peptide receptor radiotherapy (PRRT). Somatostatin analogs has for the last decades been the main stay for management for clinical symptoms related to functioning pNETs and is often combined with new targeted agents as well as chemotherapy. Long-term management of functioning pNETs need a combination of different procedures, surgery, local ablation, targeted agents and somatostatin analogs. Future therapies might be based on the recent advances in molecular genetics and tumor biology.

Carcinoid-syndrome: recent advances, current status and controversies

PURPOSE OF REVIEW

To review recent advances and controversies in all aspects of carcinoid-syndrome.

RECENT FINDINGS

Over the last few years there have been a number of advances in all aspects of carcinoid syndrome as well as new therapies. These include new studies on its epidemiology which demonstrate it is increasing in frequency; increasing insights into the pathogenesis of its various clinical manifestations and into its natural history: definition of prognostic factors; new methods to verify its presence; the development of new drugs to treat its various manifestations, both initially and in somatostatin-refractory cases; and an increased understanding of the pathogenesis, natural history and management of carcinoid heart disease. These advances have generated several controversies and these are also reviewed.

SUMMARY

There have been numerous advances in all aspects of the carcinoid-syndrome, which is the most common functional syndrome neuroendocrine tumors produce. These advances are leading to new approaches to the management of these patients and in some cases to new controversies.

Emerging use of everolimus in the treatment of neuroendocrine tumors

Neuroendocrine tumors (NETs) consist of a diverse family of malignancies, which are derived from neuroendocrine cells, most commonly originating from the gastroenteropancreatic (GEP) tract or the bronchopulmonary system. In general, NETs are more indolent than epithelial tumors, with median survival rates of longer than 30 months. The upregulation of mTOR pathway has been shown to play a pivotal role in NET pathogenesis. Inhibition of mTOR protein with everolimus represents a progress in the treatment of advanced NETs. Everolimus has shown a significant improvement in progression-free survival (PFS) among patients with pancreatic NETs (pNETs) and nonfunctional GEP and lung NETs in the Phase III RAD001 in Advanced Neuroendocrine Tumors (RADIANT)-3 and RADIANT-4 studies, respectively. In addition, the combination of everolimus with octreotide showed a clinically significant improvement versus octreotide alone in functional NETs in the RADIANT-2 trial. These studies led to the US Food and Drug Administration (FDA) and European Medical Agency (EMA) approval of everolimus. Safety profile of everolimus is generally acceptable. The most common adverse events are stomatitis, diarrhea, rash and fatigue. There is a growing range of novel treatment options in the setting of NETs, but there are no data comparing the activity of different treatment strategies. Thus, treatment decisions are based on different aspects, such as clinical course, patient symptomatology, primary tumor site, tumor functionality, rate of progression and burden of disease. Further research is required to clarify the treatment sequencing to achieve the maximum prolongation in survival and maintenance of quality of life. Future research should concentrate on identification of predictive biomarkers for benefit from different therapies, and studies should also include quality of life as an important measurement in this disease.

Refractory carcinoid syndrome: a review of treatment options

Carcinoid syndrome (CSy) is a constellation of symptoms that may commonly present in patients with well differentiated neuroendocrine tumors (NETs), with somatostatin analogs (SSAs) being the first-line option for symptom management. However, symptomatic progression eventually occurs and in this scenario of a refractory CSy; several treatment options have been studied such as dose escalation of SSA, interferon and liver-directed therapies. Nevertheless, recent phase III trials have contributed to the understanding and management of this condition. We performed a comprehensive review of interventional studies examining refractory CSy to provide the evidence for current treatment options and propose a treatment sequence.

The Influence of Preoperative Symptoms on the Death of Patients with Small Intestinal Neuroendocrine Tumors

Background

Small intestinal neuroendocrine tumors (SI-NETs) are uncommon tumors with an annual incidence of about 1 per 100,000. Usually, SI-NETs have a slow progression, and patients often present with generalized disease. Many patients do well, and the disease has a relatively favorable 5-year survival rate. Some SI-NETs, however, have a more negative prognosis. This study aimed to establish prognostic factors for death identifiable at primary surgery.

Methods

A nested case-control study investigated 1150 patients from the cohort of all patients with a diagnosis of SI-NETs in Sweden between 1961 and 2001. The study cases consisted of all patients who died of SI-NETs during the study period. Each case was assigned a control subject matched by age at diagnosis and calendar period. Possible prognostic factors [gender, degree of symptoms, indication for surgery, World Health Organization (WHO) stage] were evaluated in uni- and multivariable analyses.

Results

The patients with symptomatic disease had an increased risk of dying. The indication for primary surgery influenced survival, showing a more negative prognosis for elective surgery. The WHO stage influenced survival, and stage 4 patients had an almost threefold risk of dying compared with stages 1 to 3b patients.

Conclusions

This study showed that preoperative symptoms are important in prognostication for SI-NETs. Hormonal symptoms generally signify a patient with a more advanced disease stage and a worse prognosis. Including symptomatic disease together with the WHO stage and grade could possibly increase the accuracy of prognostication.

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.

Personalized treatment approach to gastroenteropancreatic neuroendocrine tumors: a medical oncologist's perspective

The medical management of gastroenteropancreatic neuroendocrine tumors involves treatment of symptomatic disease related to hormone secretions or bulky unresectable metastatic disease. Combining gallium DOTA with fluorine-18 fluorodeoxyglucose-PET along with histopathological grading helps to determine tumor heterogeneity and seek reasons for poor response to therapy. In the light of adding chemotherapy in selected patients with intermediate-grade tumors, the newer scan helps in personalization of the therapy along with the biopsy. The tumor dedifferentiation over the particular time period leading to aggressive behavior, a well-known entity, is contrasted with the redifferentiation phenomenon in some patients as a result of chemotherapy or targeted drug therapy. This may support the basis for combining peptide receptor-targeted radiotherapy/octreotide therapy with chemotherapy or mTOR inhibitors such as everolimus.

Management of pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (pNETs) are rare tumors that have a better prognosis than their exocrine counterpart, but frequently present with advanced disease. Management of pNETs has evolved considerably over the past decade. Surgical resection remains the only potentially curative option for patients with pNETs. Patients who have locoregionally advanced and/or metastatic pNETs require additional treatments. These include liver-directed (transarterial (chemo)-embolization, selective intraarterial radio therapy) and systemic therapies (somatostatin analogs, targeted therapy such as tyrosine-kinase inhibitors and mammalian target of rapamycin inhibitor, peptide receptor radionuclide therapy and cytotoxic chemotherapy). The aim of this article is to review the current treatment options as well as potential future therapeutic perspectives for patients with pNETs.

Ki-67 prognostic and therapeutic decision driven marker for pancreatic neuroendocrine neoplasms (PNENs): A systematic review

BACKGROUND

We systematically evaluate the current evidence regarding Ki-67 as a prognostic factor in pancreatic neuroendocrine neoplasms to evaluate the differences of this marker in primary tumors and in distant metastases as well as the values of Ki-67 obtained by fine needle aspiration and by histology.

METHODS

The literature search was carried out using the MEDLINE/PubMed database, and only papers published in the last 10 years were selected.

RESULTS

The pancreatic tissue suitable for Ki-67 evaluation was obtained from surgical specimens in the majority of the studies. There was a concordance of 83% between preoperative and postoperative Ki-67 evaluation. Pooling the data of the studies which compared the Ki-67 values obtained in both cytological and surgical specimens, we found that they were not related. The assessment of Ki-67 was manual in the majority of the papers considered for this review. In order to eliminate manual counting, several imaging methods have been developed but none of them are routinely used at present. Twenty-two studies also explored the role of Ki-67 utilized as a prognostic marker for pancreatic neuroendocrine neoplasms and the majority of them showed that Ki-67 is a good prognostic marker of disease progression. Three studies explored the Ki-67 value in metastatic sites and one study demonstrated that, in metachronous and synchronous liver metastases, there was no significant variation in the index of proliferation.

CONCLUSIONS

Ki-67 is a reliable prognostic marker for pancreatic neuroendocrine neoplasms.

Liver transplantation for the treatment of neuroendocrine liver metastases

Neuroendocrine neoplasms represent a heterogeneous group of cancers arising from a variety of neuroendocrine cell types. In general, these tumors (NET) are asymptomatic and are discovered late once metastatic disease is present (40-80%). The liver is the most common organ involved when metastases occur (40-93%), followed by bone (12-20%) and lungs (8-10%). A number of different therapeutic options are available for patients with hepatic metastases including surgical resection, transplantation, transarterial chemoembolization, radiofrequency and microwave ablation, radioembolization (Y90), chemotherapy, somatostatin analogues and molecular targeted therapies. Surgical resection is still considered the treatment of choice and provides excellent disease control with an overall survival of 47-92%. Liver transplantation has been advocated in selected patients with bilateral unresectable symptomatic liver metastases. The aim of this study is to review the existing literature emphasizing on the role of transplantation to treat patients with liver metastases from NET.

Hepatic-directed Therapies in Patients with Neuroendocrine Tumors

Neuroendocrine tumors (NETs) of the gastrointestinal (GI) tract have a propensity for producing hepatic metastases. Most GI NETs arise from the foregut or midgut, are malignant, and can cause severe debilitating symptoms adversely affecting quality of life. Aggressive treatments to reduce symptoms have an important role in therapy. Patients with GI NETs usually present with inoperable metastatic disease and severe symptoms from a variety of hormones and biogenic amines. This article describes intra-arterial hepatic-directed therapies for metastases from NETs, a group of treatments in which the therapeutic and/or embolic agents are released intra-arterially in specific hepatic vessels to target tumors.

Surgical Treatment of Small Bowel Neuroendocrine Tumors

Neuroendocrine tumors of the small bowel are rare, slow-growing malignancies that commonly metastasize to nodes at the root of the mesentery and the liver. Liver metastases are associated with carcinoid syndrome. Mesenteric nodal masses can cause bowel obstruction, intestinal angina, or variceal hemorrhage. Patients die of liver failure or bowel obstruction. Primary resection is associated with improved survival rates. Selected patients may benefit from liver debulking operations. Liver resection has excellent survival rates even in the event of an incomplete resection, as well as improvement in hormonal symptoms. Radiofrequency ablation can help to preserve hepatic parenchyma during resection.

Neuroendocrine gastro-enteropancreatic tumors - from eminence based to evidence-based medicine - A Scandinavian view

Neuroendocrine tumors (NETs) comprise a heterogenous group of neoplasms with variable clinical expression and progression. The primary tumors most frequently occur in the lungs, intestine and the pancreas. The NET incidence is approximately 6.1/100,000 per year with a prevalence higher than 35/100,000 per year. A NET may be functioning with symptoms related to hormone overproduction or non-functioning, not presenting any hormone-related symptoms. From the early 1980s and onwards, Uppsala University Hospital has contributed significantly to diagnosis, just to mention immunohistochemistry, radio-immunoassays for hormones and peptides and molecular imaging. On the therapeutic side, treatments with cytotoxics as well as biologicals such as, somatostatin analogs and interferons have been evaluated. We have furthermore been involved in important phase III trials for registration of so called, new targeted agents such as, RADIANT-3 and RADIANT-2. Our group were also the first to localize the gene for MEN I on chromosome 11 locus q13. Most recent developments have been the establishments of new biomarkers such as, olfactory receptor E51E1 as well as micro-RNAs in carcinoid tumors of the intestine and lung. A new oncolytic virus, Ad-Vince, for treatment of most NETs has been developed and is ready for the clinic. Furthermore, we have been involved in establishing Nordic and international collaborations. Today, NETs is an area with rapid development and recognized by international organizations at conferences, with large attendance. The Nordic countries continue to be significant contributors to the field.

A review on management discussions of small intestinal neuroendocrine tumors ‘midgut carcinoids’

European Neuroendocrine Tumor Society staging, together with the Ki67 grading system, has appeared as superior for classification of neuroendocrine tumors (NET). The management of small intestinal NET (SI-NET) has been overall controversial. Mesenteric metastases occur also with the smallest SI-NET, and the majority of patients risk to ultimately progress with liver metastases. 68Gallium (somatostatin receptor)/PET/CT has appeared as most sensitive for imaging, and fluorodeoxyglucose-PET is recommended to identify lesions with high proliferation. Our treatment policy for SI-NET is to initiate somatostatin analog treatment, and in order to prevent abdominal complications we recommend early intestinal resection for removal of primary tumors and clearance of lymph node metastases. Liver metastases are liberally treated by resection (or ablation), as this can efficiently palliate carcinoid syndrome-associated symptoms.

Radiofrequency ablation for neuroendocrine liver metastases: a systematic review

To determine the efficacy of radiofrequency (RF) ablation in neuroendocrine tumor (NET) liver metastases. A systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Eight studies were included (N = 301). Twenty-six percent of RF ablation procedures were percutaneous (n = 156), with the remainder conducted at surgery. Forty-eight percent of patients had a concomitant liver resection. Fifty-four percent of patients presented with symptoms, with 92% reporting symptom improvement following RF ablation (alone or in combination with surgery). The median duration of symptom improvement was 14-27 months. However, recurrence was common (63%-87%). RF ablation can provide symptomatic relief in NET liver metastases alone or in combination with surgery.

Perspectives on surgical management of neuroendocrine liver metastases

Abstract: 

Neuroendocrine tumors (NETs) commonly metastasize to the liver. Different treatments are available for the management of metastatic NETs. Both primary tumor and metastases can significantly affect the patients’ quality of life and overall survival (OS). Surgical resection is the only chance for cure and should be considered for every patient. For operable patients, current evidence suggests that liver resection is a safe and effective treatment for neuroendocrine liver metastases. High rates of recurrence are reported following resection of neuroendocrine liver metastases. There is no evidence to support incomplete (R2) resection (debulking) surgery to improve OS or quality of life. When surgery is performed for NETs, other conservative adjuvant treatments should also be considered to prolong symptom-free, disease-free and OS.

Role of hepatic intra-arterial therapies in metastatic neuroendocrine tumours (NET): guidelines from the NET-Liver-Metastases Consensus Conference

OBJECTIVES

Liver metastasis from a neuroendocrine tumour (NET) represents a significant clinical entity. A multidisciplinary group of experts was convened to develop state-of-the-art recommendations for its management.

METHODS

Peer-reviewed published reports on intra-arterial therapies for NET hepatic metastases were reviewed and the findings presented to a jury of peers. The therapies reviewed included transarterial embolization (TAE), transarterial chemoembolization (TACE) and radioembolization (RE). Two systems were used to evaluate the level of evidence in each publication: (i) the US National Cancer Institute (NCI) system, and (ii) the GRADE system.

RESULTS

Eighteen publications were reviewed. These comprised 11 reports on TAE or TACE and seven on RE. Four questions posed to the panel were answered and recommendations offered.

CONCLUSIONS

Studies of moderate quality support the use of TAE, TACE and RE in hepatic metastases of NETs. The quality and strength of the reports available do not allow any modality to be determined as superior in terms of imaging response, symptomatic response or impact on survival. Radioembolization may have advantages over TAE and TACE because it causes fewer side-effects and requires fewer treatments. Based on current European Neuroendocrine Tumor Society (ENETS) Consensus Guidelines, RE can be substituted for TAE or TACE in patients with either liver-only disease or those with limited extrahepatic metastases.

Curative versus palliative surgical resection of liver metastases in patients with neuroendocrine tumors: a meta-analysis of observational studies

BACKGROUND

The role of surgical therapy in patients with liver metastases from neuroendocrine tumors (NETs) is unclear. In this study, the results obtained with curative or palliative resection, by reviewing recent literature and performing a meta-analysis, were examined.

MATERIALS AND METHODS

A systematic review and meta-analysis of observational studies published between January 1990 and October 2013 were performed. Studies that evaluated the different survival between patients treated by curative or palliative surgical resection of hepatic metastases from NETs were considered. The collected studies were evaluated for heterogeneity, publication bias, and quality. To calculate the pooled hazard ratio (HR) estimate and the 95% confidence interval (95% CI), a fixed-effects model was applied.

RESULTS

After the literature search, 2,546 studies were found and, among 38 potentially eligible studies, 3 were considered. We did not find a significant longer survival in patients treated with curative surgical resection of hepatic metastases when compared to palliative hepatic resection HR 0.40 (95% CI: 0.14-1.11). In one study, palliative resection of hepatic metastases significantly increased survival when compared to embolization.

CONCLUSIONS

Curative and also palliative surgery of NETs liver metastases may improve survival outcome. However, further randomized clinical trials are needed to elucidate this argument.

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.

Nordic guidelines 2014 for diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms

BACKGROUND

The diagnostic work-up and treatment of patients with neuroendocrine neoplasms (NENs) has undergone major recent advances and new methods are currently introduced into the clinic. An update of the WHO classification has resulted in a new nomenclature dividing NENs into neuroendocrine tumours (NETs) including G1 (Ki67 index ≤ 2%) and G2 (Ki67 index 3-20%) tumours and neuroendocrine carcinomas (NECs) with Ki67 index > 20%, G3. Aim. These Nordic guidelines summarise the Nordic Neuroendocrine Tumour Group's current view on how to diagnose and treat NEN-patients and are meant to be useful in the daily practice for clinicians handling these patients.

Gene expression accurately distinguishes liver metastases of small bowel and pancreas neuroendocrine tumors

Small bowel (SBNETs) and pancreatic neuroendocrine tumors (PNETs) often present with liver metastases. Although liver biopsy establishes a neuroendocrine diagnosis, the primary tumor site is frequently unknown without exploratory surgery. Gene expression differences in metastases may distinguish primary SBNETs and PNETs. This study sought to determine expression differences of four genes in neuroendocrine metastases and to create a gene expression algorithm to distinguish the primary site. Nodal and liver metastases from SBNETs and PNETs (n = 136) were collected at surgery under an Institutional Review Board-approved protocol. Quantitative PCR measured expression of bombesin-like receptor-3, opioid receptor kappa-1, oxytocin receptor, and secretin receptor in metastases. Logistic regression models defined an algorithm predicting the primary tumor site. Models were developed on a training set of 21 nodal metastases and performance was validated on an independent set of nodal and liver metastases. Expression of all four genes was significantly different in SBNET compared to PNET metastases. The optimal model employed expression of bombesin-like receptor-3 and opioid receptor kappa-1. When these genes did not amplify, the algorithm used oxytocin receptor and secretin receptor expression, which allowed classification of all 136 metastases with 94.1 % accuracy. In the independent liver metastasis validation set, 52/56 (92.9 %) were correctly classified. Positive predictive values were 92.5 % for SBNETs and 93.8 % for PNETs. This validated algorithm accurately distinguishes SBNET and PNET metastases based on their expression of four genes. High accuracy in liver metastases demonstrates applicability to the clinical setting. Studies assessing this algorithm's utility in prospective clinical decision-making are warranted.

Pancreastatin predicts survival in neuroendocrine tumors

BACKGROUND

Serum neurokinin A, chromogranin A, serotonin, and pancreastatin reflect tumor burden in neuroendocrine tumors. We sought to determine whether their levels correlate with survival in surgically managed small bowel (SBNETs) and pancreatic neuroendocrine tumors (PNETs).

METHODS

Clinical data were collected with Institutional Review Board approval for patients undergoing surgery at one center. Progression-free (PFS) and overall (OS) survival were from the time of surgery. Event times were estimated by the Kaplan-Meier method. Preoperative and postoperative laboratory values were tested for correlation with outcomes. A multivariate Cox model adjusted for confounders.

RESULTS

Included were 98 SBNETs and 78 PNETs. Median follow-up was 3.8 years; 62 % had metastatic disease. SBNETs had lower median PFS than PNETs (2.0 vs. 5.6 years; p < 0.01). Median OS was 10.5 years for PNETs and was not reached for SBNETs. Preoperative neurokinin A did not correlate with PFS or OS. Preoperative serotonin correlated with PFS but not OS. Higher levels of preoperative chromogranin A and pancreastatin showed significant correlation with worse PFS and OS (p < 0.05). After multivariate adjustment for confounders, preoperative and postoperative pancreastatin remained independently predictive of worse PFS and OS (p < 0.05). Whether pancreastatin normalized postoperatively further discriminated outcomes. Median PFS was 1.7 years in patients with elevated preoperative pancreastatin versus 6.5 years in patients with normal levels (p < 0.001).

CONCLUSIONS

Higher pancreastatin levels are significantly associated with worse PFS and OS in SBNETs and PNETs. This effect is independent of age, primary tumor site, and presence of nodal or metastatic disease. Pancreastatin provides valuable prognostic information and identifies surgical patients at high risk of recurrence who could benefit most from novel therapies.

Outcome after resection and radiofrequency ablation of liver metastases from small intestinal neuroendocrine tumours

BACKGROUND

In patients with small intestinal neuroendocrine tumour (SI-NET), liver resection or radiofrequency ablation (RFA) of liver metastases is performed for palliation of carcinoid syndrome, and in an effort to improve survival. Data are generally reported from case series, and no randomized trials have studied these treatments. The aim was to compare outcome after liver resection and/or RFA with that of non-surgical treatment in patients with liver metastases from SI-NET.

METHODS

The study included patients with liver metastases from SI-NET who underwent liver RFA/resection or were treated non-surgically. A propensity score match was performed to reduce bias between groups, using baseline variables such as the Charlson co-morbidity index, age, symptoms, carcinoid heart disease, extent of metastases and proliferation index.

RESULTS

Some 103 patients who had RFA and/or liver resection were compared with 273 controls. Propensity score matching resulted in two matched groups, each of 72 patients, with no significant differences in baseline variables. The matched resection/RFA and control groups showed no difference in overall survival (both 74 per cent at 5 years; P = 0·869) or disease-specific survival (74 versus 78 per cent respectively at 5 years; P = 1·000). However, urinary 5-hydroxyindoleacetic acid levels were lower (median 77 versus 120 µmol per 24 h; P = 0·005) and the proportion of patients with progressive disease within the liver was smaller (2 of 18 versus 8 of 18; P < 0·001) in the resection/RFA group after 5 years.

CONCLUSION

These data do not support the use of liver resection and/or RFA in an effort to prolong survival in patients with liver metastases from SI-NET.

[Diagnosis and treatment options of neuroendocrine tumours]

Neuroendocrine neoplasms belong to the group of rare tumours. Their clinical importance may be highlighted by their high prevalence despite low incidence. Since survival rate is similar to other progressive neoplastic diseases in metastatic cases, early recognition and appropriate therapy of these neoplasms are equally important. Classification of neuroendocrine tumours is based on their pathologic characteristics according to the 2010 WHO recommendation. Non-functioning tumours cause local symptoms due to their mass effect, while functioning tumours produce well-defined endocrine syndromes. Among laboratory tests, serum chromogranin-A is considered the most important biomarker of both non-functioning and functioning neuroendocrine tumours. Localization of these tumours includes the use of conventional diagnostic imaging, endoscopic examinations, and functional imaging studies. With respect to treatment, elimination of the primary tumour remains one of the most important issues. In advanced cases of the disease metastasectomy, interventional radiologic methods, medical treatment and endoradiotherapy can be used. The aim of this review is to summarize briefly the symptoms, diagnostic methods and treatment options of neuroendocrine tumours.

Adjunctive radiofrequency ablation of metastatic neuroendocrine cancer to the liver complements surgical resection

BACKGROUND

Resection of liver metastases from neuroendocrine cancer (NEC) prolongs survival and provides durable symptom relief. Not all hepatic lesions are amenable to resection, particularly when there is multifocal involvement. In this study, it was hypothesized that ablation of concomitant non-resectable NEC liver metastases is safe and salvages patients who would not have been selected for cytoreductive surgery.

METHODS

  Patients who underwent adjuvant ablation of NEC liver metastases between 1995 and 2008 were reviewed. NEC was classified by patient and tumour characteristics. Regression and Kaplan-Meier models were used to compare variables and generate survival curves.

RESULTS

  Ninety-four patients underwent hepatic resection and intra-operative ablation of metastatic NEC. The median number of lesions ablated was 3, and median size was 1.4 cm. One abscess occurred at an ablation site. Local recurrence was detected in four patients (3.8%). Overall survival was 80% and 59% at 5 and 10 years. Age, gender, tumour type, grade, primary site and need for repeat ablation had no significant association with survival. The Ki67 proliferative index was a significant predictor of decreased survival. Symptom-free survival was 34% at 3 years and 16% at 5 years, independent of the tumour grade.

CONCLUSION

Concurrent ablation of NEC metastases to the liver not amenable to resection is safe and increases the candidacy of patients for cytoreductive surgery. Ablation performed intra-operatively and repeated post-operatively as needed provides significant symptom control regardless of the tumour grade.

Ki67 proliferation index, hepatic tumor load, and pretreatment tumor growth predict the antitumoral efficacy of lanreotide in patients with malignant digestive neuroendocrine tumors

BACKGROUND

An antiproliferative effect of somatostatin analogs was recently demonstrated.

AIM

To identify factors associated with tumor control in a group of patients with well-differentiated malignant digestive neuroendocrine tumors treated with lanreotide.

METHODS

A retrospective study was conducted in 68 patients treated with lanreotide alone, with progression-free survival as the primary endpoint. The role of the following factors was searched for by univariate and multivariate analyses: age, sex, mode of discovery, site of the primary tumor, metastatic spread, Ki67 proliferation index, uptake on somatostatin receptor scintigraphy, pretreatment tumor growth, extent of liver involvement, resection of primary tumor, previous treatments, and tumor markers.

RESULTS

Tumor progression was observed in 39/68 patients (57.4%). Median progression-free survival was 29 months. On multivariate analysis, a Ki67 proliferation index of up to 5% [hazard ratio (HR)=0.262, P=0.009], pretreatment stability (HR=0.241, P=0.008), and hepatic tumor load of up to 25% (HR=0.237, P=0.004) were significantly associated with disease stability under lanreotide therapy.

CONCLUSION

In patients with well-differentiated malignant digestive neuroendocrine tumors, Ki67 proliferation index of up to 5%, stable disease before treatment, and low-to-moderate hepatic tumor involvement (≤ 25%) are associated with tumor control during lanreotide treatment. These data if confirmed in prospective trials will help in rationalizing the use of somatostatin analogs with antiproliferative intent.