New treatment strategies in advanced neuroendocrine tumours

Neuroendocrine Tumours of Extrahepatic Biliary Tract: Report of Four Cases with Literature Review

Neuroendocrine tumours (NETs) originating from extrahepatic bile duct are an extremely rare entity. They are typically slow growing tumours with malignant potential. Commonly presenting as obstructive jaundice, preoperative clinico-radiologic differentiation between extrahepatic biliary tract neuroendocrine tumours and cholangiocarcinoma is difficult and the final diagnosis is usually established after surgical histopathology and immunohistochemistry examination. R0 resection offers the only curative option with good long-term outcomes for well-differentiated NETs (grade1, grade2, and grade3) while the aggressive poorly differentiated neuroendocrine carcinoma (NEC) needs multimodality approach. We present our experience of management of four cases including three cases of grade II NET and one case of NEC undergoing surgical resection at a single centre with a short review of available literature.

Diagnostic and Predictive Role of DLL3 Expression in Gastroenteropancreatic Neuroendocrine Neoplasms

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are a rare and heterogeneous subgroup of tumors with a challenging management because of their extremely variable biological and clinical behaviors. Due to their different prognosis, there is an urgent need to identify molecular markers which would enable to discriminate between grade 3 neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs), despite both being diagnosed mainly on the basis of proliferation index and cell differentiation. DLL3, a negative Notch regulator, is a promising molecular target highly expressed in several tumors with neuroendocrine features. We conducted a retrospective analysis of DLL3, RB1, and PD-L1 expression by immunohistochemistry (IHC), in formalin-fixed, paraffin-embedded (FFPE) samples from 47 patients with GEP-NENs. Then, we correlated the results with patients' clinical features and outcome. The absence of DLL3 expression in 5 well-differentiated GEP-NETs with high-grade features (G3 NET), and the presence of DLL3 in 76.9% of poorly-differentiated NECs (G3 NEC), highlights DLL3 expression as a marker of G3 NECs (p = 0.007). DLL3 expression was correlated with RB1-loss (p < 0.001), negative ⁶⁸ Ga-PET/CT scan (p = 0.001), and an unfavorable clinical outcome, with important implications for treatment response and patient's follow-up. Median progression-free survival (PFS) and overall survival (OS) were 22.7 months (95% CI 6.1-68.8) and 68.8 months (95% CI 26.0-78.1), respectively, in patients with DLL3-negative tumor compared with 5.2 months (95% CI 2.5-18.5) and 9.5 months (95% CI 2.5-25.2), respectively, in patients with DLL3-positive tumor (PFS p = 0.0083, OS p = 0.0071). Therefore, combined with morphological cell analysis, DLL3 could represent a valuable histological marker, for the diagnosis of poorly differentiated NECs. The high percentage of DLL3 expression in NEC patients also highlights a potential opportunity for a DLL3 targeted therapy in this tumor subset.

Cryotherapy for liver metastases

BACKGROUND

The liver is affected by two of the most common groups of malignant tumours: primary liver tumours and liver metastases from colorectal carcinoma. Liver metastases are significantly more common than primary liver cancer and long-term survival rates reported for patients after radical surgical treatment is approximately 50%. However, R0 resection (resection for cure) is not feasible in the majority of patients. Cryotherapy is performed with the use of an image-guided cryoprobe which delivers liquid nitrogen or argon gas to the tumour tissue. The subsequent process of freezing is associated with formation of ice crystals, which directly damage exposed tissue, including cancer cells.

OBJECTIVES

To assess the beneficial and harmful effects of cryotherapy compared with no intervention, other ablation methods, or systemic treatments in people with liver metastases.

SEARCH METHODS

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid, Embase Ovid, and six other databases up to June 2018.

SELECTION CRITERIA

Randomised clinical trials assessing beneficial and harmful effects of cryotherapy and its comparators for liver metastases, irrespective of the location of the primary tumour.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We extracted information on participant characteristics, interventions, study outcomes, and data on the outcomes important for our review, as well as information on the design and methodology of the trials. Two review authors independently assessed risk of bias in each study. One review author performed data extraction and a second review author checked entries.

MAIN RESULTS

We found no randomised clinical trials comparing cryotherapy versus no intervention or versus systemic treatments; however, we identified one randomised clinical trial comparing cryotherapy with conventional surgery. The trial was conducted in Ukraine. The trial included 123 participants with solitary, or multiple unilobar or bilobar liver metastases; 63 participants received cryotherapy and 60 received conventional surgery. There were 36 women and 87 men. The primary sites for the metastases were colon and rectum (66.6%), stomach (7.3%), breast (6.5%), skin (4.9%), ovaries (4.1%), uterus (3.3%), kidney (3.3%), intestines (1.6%), pancreas (1.6%), and unknown (0.8%). The trial was not reported sufficiently enough to assess the risk of bias of the randomisation process, allocation concealment, or presence of blinding. It was also not possible to assess incomplete outcome data and selective outcome reporting bias. The certainty of evidence was low because of risk of bias and imprecision.The participants were followed for up to 10 years (minimum five months). The trial reported that the mortality at 10 years was 81% (51/63) in the cryotherapy group and 92% (55/60) in the conventional surgery group. The calculated by us relative risk (RR) with 95% Confidence Interval (CI) was: RR 0.88, 95% CI 0.77 to 1.02. We judged the evidence as low-certainty evidence. Regarding adverse events and complications, separately and in total, our calculation showed no evidence of a difference in recurrence of the malignancy in the liver: 86% (54/63) of the participants in the cryotherapy group and 95% (57/60) of the participants in the conventional surgery group developed a new malignancy (RR 0.90, 95% CI 0.80 to 1.01; low-certainty evidence). The frequency of reported complications was similar between the cryotherapy group and the conventional surgery group, except for postoperative pain. Both insignificant and pronounced pain were reported to be more common in the cryotherapy group while intense pain was reported to be more common in the conventional surgery group. However, the authors did not report whether there was any evidence of a difference. There were no intervention-related mortality or bile leakages.We identified no evidence for health-related quality of life, cancer mortality, or time to progression of liver metastases. The study reported tumour response in terms of the carcinoembryonic antigen level in 69% of participants, and reported results in the form of a graph for 30% of participants. The carcinoembryonic antigen level was lower in the cryotherapy group, and decreased to normal values faster in comparison with the control group (P < 0.05).

FUNDING

the trial did not provide information on funding.

AUTHORS' CONCLUSIONS

The evidence for the effectiveness of cryotherapy versus conventional surgery in people with liver metastases is of low certainty. We are uncertain about our estimate and cannot determine whether cryotherapy compared with conventional surgery is beneficial or harmful. We found no evidence for the benefits or harms of cryotherapy compared with no intervention, or versus systemic treatments.

Cerebellar Metastasis of Unknown Primary Neuroendocrine Carcinoma: Report of Case Mimicking Hemangioblastoma

BACKGROUND

Neuroendocrine carcinoma (NEC) originates with neuroendocrine cells and is mainly found in the pancreas, lungs and gastrointestinal tract. We surgically treated a case of primary unknown NEC with only cerebral metastasis that mimicked hemangioblastoma. Recurrence was seen at the fornix, and no primary lesion had been identified as of 2 years after treatments despite careful examination.

CASE DESCRIPTION

A 61-year-old man presented with dizziness. Past medical history included hypertension, dyslipidemia, hyperuricemia and colon polyp. We performed magnetic resonance imaging (MRI) to examine the cause of dizziness, revealing tumor with enhancement and peritumoral edema at the right cerebral lesion. Contrast-enhanced whole-body computed tomography (CT) showed no other lesions. We suspected hemangioblastoma from examinations and decided on surgical resection. Neuropathologically, the resected tumor was diagnosed as brain metastasis of NEC, but CT, fluorodeoxyglucose-positron emission tomography, gastrointestinal endoscopy, and somatostatin receptor scintigraphy all failed to reveal the primary lesion. As postoperative MRI showed enhancement around the resection cavity and at the right fornix, radiotherapy was performed. No other lesions were seen at 24 months postoperatively. We are continuing careful monitoring and no chemotherapy has been administered.

CONCLUSIONS

We treated brain metastasis from NEC of unknown primary and mimicking hemangioblastoma using only local treatment. When an enhancing, single, solid tumor is seen in the cerebellum, brain metastasis from NEC of unknown primary is 1 differential diagnosis.

O6-methylguanine-DNA methyltransferase (MGMT) status in neuroendocrine tumors: a randomized phase II study (MGMT-NET)

INTRODUCTION

Neuroendocrine tumors (NETs) are rare, but their incidence is rising. Alkylating agents (ALKY), temozolomide and streptozotocin, are the main chemotherapies used for advanced pancreatic NETs. According to retrospective data, O6-methylguanine-DNA methyltransferase (MGMT) status appears to be a predictive factor of the response to ALKY.

AIMS

The main objective is to evaluate the value of tumor MGMT promoter (pMGMT) methylation in the prediction of the objective response (OR) at 3 months in patients treated with ALKY. Secondly, we will evaluate the value of MGMT immunohistochemistry and the efficacy of treatment with ALKY vs. oxaliplatin-based chemotherapy (Ox).

MATERIALS AND METHODS

A national, prospective, open-label, randomized, controlled and multicenter trial was designed. Main inclusion criteria are: adult patients with well-differentiated advanced duodeno-pancreatic, lung, or unknown primitive NETs with a validated indication for chemotherapy. pMGMT methylation will be assessed by pyrosequencing, but an ancillary study will compare this technique with others ones including MGMT immunohistochemistry.

RESULTS

A total of 104 patients will be randomly assigned (1:1 for unmethylated or 2:1 for methylated pMGMT NETs) to either the ALKY arm or to the Ox arm.

CONCLUSION

Recruitment started on October 16, 2018 (NCT03217097) and will be open in 21 centers in France.

Preoperative diagnosis of well-differentiated neuroendocrine tumor in common hepatic duct by brush cytology: A case report

The biological behavior of neuroendocrine tumors (NETs) is heterogeneous and differs from that of cholangiocarcinoma, which is the most common malignant tumor of the biliary tree. However, the preoperative diagnosis of NET in the biliary tree is extremely difficult and to our knowledge, diagnosis by brush cytology has not previously been reported. Herein, we first reported a case of biliary NET preoperatively diagnosed by brush cytology in a 33-year-old female patient. Imaging study revealed a 2.6-cm mass in the common hepatic duct. The brush cytology was characterized by loosely cohesive plasmacytoid tumor cells and scattered clusters of thin vascular septa. The tumor cells showed abundant cytoplasm and severe nuclear size variation but mitosis was not observed. Immunohistochemical staining of the cell block (CB) showed strong positivity for both synaptophysin and chromogranin A and a Ki-67 labeling index of 3.5%. The surgically resected bile duct mass was pathologically confirmed as NET, G2 with lymphovascular and perineural invasion of the tumor cells. The patient showed no evidence of tumor recurrence 10 months after operation without adjuvant chemotherapy. Suspicion of this rare tumor and immunohistochemical staining of the CB are important for the preoperative diagnosis of NET in the biliary tree.

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.

Molecular Genetic Studies of Pancreatic Neuroendocrine Tumors: New Therapeutic Approaches

Pancreatic neuroendocrine tumors (PNETs) arise sporadically or as part of familial syndromes. Genetic studies of hereditary syndromes and whole exome sequencing analysis of sporadic NETs have revealed the roles of some genes involved in PNET tumorigenesis. The multiple endocrine neoplasia type 1 (MEN1) gene is most commonly mutated. Its encoded protein, menin, has roles in transcriptional regulation, genome stability, DNA repair, protein degradation, cell motility and adhesion, microRNA biogenesis, cell division, cell cycle control, and epigenetic regulation. Therapies targeting epigenetic regulation and MEN1 gene replacement have been reported to be effective in preclinical models.

Current and emerging therapies for PNETs in patients with or without MEN1

Pancreatic neuroendocrine tumours (PNETs) might occur as a non-familial isolated endocrinopathy or as part of a complex hereditary syndrome, such as multiple endocrine neoplasia type 1 (MEN1). MEN1 is an autosomal dominant disorder characterized by the combined occurrence of PNETs with tumours of the parathyroids and anterior pituitary. Treatments for primary PNETs include surgery. Treatments for non-resectable PNETs and metastases include biotherapy (for example, somatostatin analogues, inhibitors of receptors and monoclonal antibodies), chemotherapy and radiological therapy. All these treatments are effective for PNETs in patients without MEN1; however, there is a scarcity of clinical trials reporting the efficacy of the same treatments of PNETs in patients with MEN1. Treatment of PNETs in patients with MEN1 is challenging owing to the concomitant development of other tumours, which might have metastasized. In recent years, preclinical studies have identified potential new therapeutic targets for treating MEN1-associated neuroendocrine tumours (including PNETs), and these include epigenetic modification, the β-catenin-wingless (WNT) pathway, Hedgehog signalling, somatostatin receptors and MEN1 gene replacement therapy. This Review discusses these advances.

Neuroendocrine tumor of the extrahepatic bile duct: A case report

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Neuroendocrine tumors of the extrahepatic bile ducts are extremely rare neoplasms.

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They most commonly occur in young females and usually present with painless jaundice.

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Preoperative diagnosis is difficult because the findings are similar to other biliary malignancies.

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Surgical resection is considered to be the only curative treatment.

Introduction

Neuroendocrine tumors (NETs) of the extrahepatic bile ducts are extremely rare neoplasms arising from endocrine cells and have variable malignant potential. They most commonly occur in young females and usually present with painless jaundice.

Presentation of case

Here we present the case of an asymptomatic 57-year-old woman with NET of the common bile duct that was incidentally discovered on abdominal ultrasound during a medical examination. She was admitted to our hospital with a diagnosis of hepatic hilar tumor. Computed tomography revealed the tumor surrounding the hepatic hilum and duodenum. Magnetic resonance cholangiopancreatography revealed a filling defect of the common bile duct with morphology suggestive of external compression. Endoscopic ultrasound confirmed a submucosal tumor of the duodenal bulb measuring 30 × 20 mm in size. The patient qualified for surgery with a preoperative diagnosis of submucosal tumor of the duodenal bulb. Intraoperative examination revealed that the tumor location involved the common bile duct and/or cystic duct with no signs of invasion to other organs or metastatic lymph nodes. Excision of the biliary ducts and tumor was followed by Roux-en-Y anastomosis. Histological results showed NET grade 1.

Discussion

Preoperative diagnosis of NETs is difficult because of their rarity. A definitive diagnosis is usually established intraoperatively or after histopathological evaluation.

Conclusion

For these tumors, surgical resection is currently the only treatment modality for achieving a potentially curative effect and prolonged disease-free survival.

Unravelling the pharmacologic opportunities and future directions for targeted therapies in gastro-intestinal cancers part 2: Neuroendocrine tumours, hepatocellular carcinoma, and gastro-intestinal stromal tumours

Until the 1990s, cytotoxic chemotherapy has been the cornerstone of medical therapy for gastrointestinal (GI) cancers. Better understanding of the cancer cell molecular biology has led to the therapeutic revolution of targeted therapies, i.e. monoclonal antibodies or small molecule inhibitors directed against proteins that are specifically overexpressed or mutated in cancer cells. These agents, being more specific to cancer cells, were expected to be less toxic than conventional cytotoxic agents. However, their effects have sometimes been disappointing, due to intrinsic or acquired resistance mechanisms, or to an activity restricted to some tumour settings, illustrating the importance of patient selection and early identification of predictive biomarkers of response to these therapies. Targeted agents have provided clinical benefit in many GI cancer types. Particularly, some GI tumours are considered chemoresistant and targeted therapies have offered a new therapeutic base for their management. Hence, somatostatin receptor-directed strategies, sorafenib, and imatinib have revolutioned the management of neuroendocrine tumours (NET), hepatocellular carcinoma (HCC), and gastrointestinal stromal tumours (GIST), respectively, and are now used as first-line treatment in many patients affected by these tumours. However, these agents face problems of resistances and identification of predictive biomarkers from imaging and/or biology. We propose a comprehensive two-part review providing a panoramic approach of the successes and failures of targeted agents in GI cancers to unravel the pharmacologic opportunities and future directions for these agents in GI oncology. In this second part, we will focus on NET, HCC, and GIST, whose treatment relies primarily on targeted therapies.

Evaluating lanreotide as maintenance therapy after first-line treatment in patients with non-resectable duodeno-pancreatic neuroendocrine tumours

INTRODUCTION

Patients with metastatic or locally advanced, non-resectable, grade 1 or 2 well-differentiated duodeno-pancreatic (WDDP) NETs are treated following European guidelines. Patients (Pts) with aggressive disease, i.e. progressive and/or symptomatic metastases and/or with significant hepatic invasion (>30-50%), and/or bone metastases, anti-tumour therapy should receive systemic combination of chemotherapy once disease control is obtained.

AIM(S)

The aim is to stop chemotherapy until progression. REMINET is an academic randomized, double-blind, placebo-controlled, phase II/III study designed to evaluate lanreotide (LAN) as maintenance treatment after L1 chemotherapy in G1-G2 WDDP NET.

MATERIALS AND METHODS

Main eligibility criteria: adults pts with a metastatic (synchronous or metachronous) or locally advanced, non-resectable, grade 1 or 2 WDDP NETs and documented control disease after L1 therapy at least 4 weeks prior to randomization.

RESULTS

222 patients will be randomly assigned in a 1:1 ratio to receive 120mg LAN or placebo, every 28 days, until disease progression or unacceptable toxicity. The aim of the phase II part is to demonstrate a 6-months PFS >45% in LAN arm. Secondary endpoints are PFS according to central review, overall survival, safety and quality of life. A bio-bank of frozen blood will be constituted.

CONCLUSION

The study is currently open in France, Germany, Belgium, United Kingdom and Ireland. A total of 25 patients are randomized (NCT02288377).

Is there still a role for the hepatic locoregional treatment of metastatic neuroendocrine tumors in the era of systemic targeted therapies?

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) frequently present with distant metastases at the time of diagnosis and the liver is the most frequent site of spreading. The early identification of metastatic disease represents a major prognostic factor for GEP-NENs patients. Radical surgical resection, which is feasible for a minority of patients, is considered the only curative option, while the best management for patients with unresectable liver metastases is still being debated. In the last few years, a number of locoregional and systemic treatments has become available for GEP-NEN patients metastatic to the liver. However, to date only a few prospective studies have compared those therapies and the optimal management option is based on clinical judgement. Additionally, locoregional treatments appear feasible and safe for disease control for patients with limited liver involvement and effective in symptoms control for patients with diffuse liver metastases. Considering the lack of randomized controlled trials comparing the locoregional treatments of liver metastatic NEN patients, clinical judgment remains key to set the most appropriate therapeutic pathway. Prospective data may ultimately lead to more personalized and optimized treatments. The present review analyzes all the locoregional therapy modalities (i.e., surgery, ablative treatments and transarterial approach) and aims to provide clinicians with a useful algorithm to best treat GEP-NEN patients metastatic to the liver.

Small intestinal neuroendocrine tumors with liver metastases and resection of the primary: Prognostic factors for decision making

INTRODUCTION

Patients with small intestine neuroendocrine tumors present with liver metastases in 50-75% of cases at diagnosis. The aim of the present study was to assess prognostic factors in patients with liver metastases from intestinal neuroendocrine tumor after primary tumor surgical removal with or without liver surgery or radiofrequency ablation. The primary endpoint was disease-specific survival.

METHODS

Data regarding seventy-eight consecutive patients with liver metastases who undergone primary tumor surgical removal between 1996 and 2011 were extracted from the institutional tumor registry and retrospectively analyzed.

RESULTS

Liver tumor burden was <25% in 43 (55.1%) 25-50% in 30 (38.5%) and >50% in 5 (6.4%) patients. For the whole cohort of patients disease-specific survival at 3, 5 and 8 years was 93.2%, 83.6% and 77.3%, respectively. Fifteen patients who underwent radical liver surgery were all alive with a median survival of 106 months (range 18-152 months). In multivariate analysis the Ki-67 index in a continuous fashion significantly correlate with prognosis (p = 0.021). Liver tumor burden (p = 0.036) and extrahepatic involvement (p = 0.03), were the most powerful prognosticators for patients who underwent only debulking surgery.

CONCLUSION

The Ki-67 index, the liver tumor burden and the presence of extrahepatic metastases should be carefully considered in the selection criteria for liver debulking in asymptomatic patients.

Gemcitabine and oxaliplatin or alkylating agents for neuroendocrine tumors: Comparison of efficacy and search for predictive factors guiding treatment choice

BACKGROUND

The alkylating agents (ALKYs) streptozotocin, dacarbazine, and temozolomide currently are the main drugs used in systemic chemotherapy for neuroendocrine tumors (NETs). The promising activity shown by gemcitabine and oxaliplatin (GEMOX) in previous studies prompted this study 1) to confirm the use of GEMOX in a larger population of NET patients, 2) to compare its efficacy with that of ALKYs, and 3) to explore whether the O(6) -methylguanine-DNA methyltransferase (MGMT) status could help in selecting the chemotherapy regimen.

METHODS

One hundred four patients with metastatic NETs (37 pancreatic NETs, 33 gastrointestinal NETs, 23 bronchial NETs, and 11 NETs of other/unknown origin) were treated with GEMOX between 2004 and 2014. Among these patients, 63 also received ALKYs. MGMT promoter gene methylation was assessed via pyrosequencing in 42 patients.

RESULTS

Patients received a median of 6 courses of GEMOX. Twenty-four (23%) had an objective response (OR). The median progression-free survival (PFS) and overall survival were 7.8 and 31.6 months, respectively. In the 63 patients treated with both ALKYs and GEMOX, the ORs (22% and 22%) and the PFSs (7.5 and 7.3 months) were similar. The response was concordant in 53% of the patients. Promoter gene methylation of MGMT was associated with better outcomes with ALKYs (P = .03 for OR and P = .04 for PFS) but not GEMOX.

CONCLUSIONS

GEMOX is effective against NETs; its activity is comparable to that of ALKYs, and it is not influenced by the MGMT status. Our data suggest that GEMOX might be preferred for patients with unmethylated MGMT tumors. Cancer 2015;121:3435-43. © 2015 American Cancer Society.

O6-Methylguanine-DNA methyltransferase status in neuroendocrine tumours: prognostic relevance and association with response to alkylating agents

Background:

O⁶-Methylguanine-DNA methyltransferase (MGMT) loss of expression has been suggested to be predictive of response to temozolomide in neuroendocrine tumours (NETs), but so far, only limited data are available. We evaluated the prognostic and predictive value of MGMT status, assessed by two molecular methods and immunohistochemistry, in a large series of NETs of different origins.

Methods:

A total of 107 patients, including 53 treated by alkylants (temozolomide, dacarbazine or streptozotocin), were retrospectively studied. In each case, we used methyl-specific PCR (MS-PCR) and pyrosequencing for evaluation of promoter methylation and immunohistochemistry for evaluation of protein status.

Results:

MGMT promoter methylation was detected in 12 out of 99 (12%) interpretable cases by MS-PCR and in 24 out of 99 (24%) by pyrosequencing. O⁶-Methylguanine-DNA methyltransferase loss of expression was observed in 29 out of 89 (33%) interpretable cases. Status of MGMT was not correlated with overall survival (OS) from diagnosis. Progression-free survival and OS from first alkylant use (temozolomide, dacarbazine and streptozotocin) were higher in patients with MGMT protein loss (respectively, 20.2 vs 7.6 months, P<0.001 and 105 vs 34 months, P=0.006) or MGMT promoter methylation assessed by pyrosequencing (respectively, 26.4 vs 10.8 months, P=0.002 and 77 vs 43 months, P=0.026).

Conclusions:

Our results suggest that MGMT status is associated with response to alkylant-based chemotherapy in NETs.

Catheter-based treatments for hepatic metastases from neuroendocrine tumors

OBJECTIVE

The purpose of this article is to present our experience in treating patients with hepatic metastases from a neuroendocrine primary malignancy.

CONCLUSION

The tumor and patient characteristics, vascular access, and features of treatment all play a role in the long-term management of patients with metatastic neuroendocrine tumors. Routine prophylactic measures are recommended to reduce the frequency and severity of crisis events related to hormone release in patients with neuroendocrine tumors.

Therapy for metastatic pancreatic neuroendocrine tumors

BACKGROUND

Pancreatic neuroendocrine tumors (pNETs) are frequently malignant (50-80%, except for insulinoma) and may show an aggressive course with metastases to the liver as well as more distant sites. These heterogeneous neoplasms include functioning tumors, which secrete a variety of peptide hormones, and non-functioning tumors (up to 90% of pNETs), which often show metastases at the time of diagnosis.

METHODS

A PubMed search was performed for English-language publications from 1995 through December 2012. Reference lists from studies selected were manually searched to identify further relevant reports. Manuscripts comparing different therapeutic options and advances for metastatic pNETs were selected.

RESULTS

The therapeutic options for metastatic pNETs are expanding and include surgery, which remains the only curative approach, liver-directed therapies, and medical therapy. In selected cases also liver transplantation (OLT) may be considered. The option of OLT for metastatic disease is unique to neuroendocrine tumors. Recently, novel promising targeted therapies have been proposed for progressive well-differentiated pNETs.

CONCLUSIONS

The best therapeutic approach for pNETs is still matter of debating. However, since pNETs often show a more indolent behavior compared to other malignancies, the preservation of the quality of life of the patient and the personalization of the therapy according to tumor's and patient's features are mandatory.

Neuroendocrine tumors of extrahepatic biliary tract

Neuroendocrine tumors of the extrahepatic bile ducts (EBNETs) are very rare. The aim of the present review is to elucidate the characteristics of EBNETs, their treatment and prognosis. An exhaustive systematic review of the literature was performed from 1959 up-to-date. One hundred articles, describing 150 cases were collected. Each article was carefully analyzed and a database was created. The most common symptoms were jaundice (60.3 %) and pruritus (19.2 %). Cholelithiasis co-existed in 15 cases (19.2 %). Hormone- and vasoactive peptide- related symptoms were present in only 7 cases (9 %). The most frequent sites were found to be the common hepatic duct and the proximal common bile duct (19.2 %). Surgical management was considered the main treatment for EBNETs, while excision of extrahepatic biliary tree (62.82 %) with portal vein lymphadenectomy (43.6 %) was the most popular procedure. EBNETs are extremely rare. Their rarity makes their characterization particularly difficult. Up to date the final diagnosis is made after surgery by pathology and immunohistochemistry findings. The present analysis of the existing published cases elucidates many aspects of these tumours, giving complete clinicopathological documentation.

[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.

Gastroenteropancreatic endocrine tumors

Gastroenteropancreatic endocrine tumors (GEP-NETs) are relatively uncommon; comprising approximately 0.5% of all human cancers. Although they often exhibit relatively indolent clinical courses, GEP-NETs have the potential for lethal progression. Due to their scarcity and various technical challenges, GEP-NETs have been understudied. As a consequence, we have few diagnostic, prognostic and predictive biomarkers for these tumors. Early detection and surgical removal is currently the only reliable curative treatment for GEP-NET patients; many of whom, unfortunately, present with advanced disease. Here, we review the genetics and epigenetics of GEP-NETs. The last few years have witnessed unprecedented technological advances in these fields, and their application to GEP-NETS has already led to important new information on the molecular abnormalities underlying them. As outlined here, we expect that "omics" studies will provide us with new diagnostic and prognostic biomarkers, inform the development of improved pre-clinical models, and identify novel therapeutic targets for GEP-NET patients.

Nonsurgical Strategies in Patients With NET Liver Metastases: A Protocol of Four Systematic Reviews

BACKGROUND

Patients diagnosed with neuroendocrine tumors (NETs) with hepatic metastases generally have a worse prognosis as compared with patients with nonmetastasized NETs. Due to tumor location and distant metastases, a surgical approach is often not possible and nonsurgical therapeutic strategies may apply.

OBJECTIVE

The aim of these systematic reviews is to evaluate the role of nonsurgical therapy options for patients with nonresectable liver metastases of NETs.

METHODS

An objective group of librarians will provide an electronic search strategy to examine the MEDLINE, EMBASE, and The Cochrane Library (Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials [CENTRAL]) databases. There will be no restriction concerning language and publication date. The qualitative and quantitative synthesis of the systematic review will be conducted with randomized controlled trials (RCT), prospective, and retrospective comparative cohort, and case-control studies. Case series will be collected in a separate database and only used for descriptive purposes.

RESULTS

This study is ongoing and presents a protocol of four systematic reviews to assess the role of nonsurgical treatment options in patients with neuroendocrine liver metastases.

CONCLUSIONS

These systematic reviews, performed according to this protocol, will assess the value of noninvasive therapy options for patients with nonresectable liver metastases of NETs in combination with invasive techniques, such as percutaneous liver-directed techniques and local ablation techniques.

TRIAL REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO): CRD42012002657; http://www.metaxis.com/PROSPERO/full_doc.asp?RecordID=2657 (Archived by WebCite at http://www.webcitation.org/6NDlYi37O); CRD42012002658; http://www.metaxis.com/PROSPERO/full_doc.asp?RecordID=2658 (Archived by WebCite at http://www.webcitation.org/6NDlfWSuD); CRD42012002659; www.metaxis.com/PROSPERO/full_doc.asp?RecordID=2659 (Arichived by Webcite at http://www.webcitation.org/6NDlmWAFM); and CRD42012002660; http://www.metaxis.com/PROSPERO/full_doc.asp?RecordID=2660 (Archived by WebCite at http://www.webcitation.org/6NDmnylzp).

Treatment of malignant pancreatic neuroendocrine neoplasms: middle-term (2-year) outcomes of a prospective observational multicentre study

BACKGROUND

Information on malignant pancreatic neuroendocrine neoplasms (pNENs) is mostly from retrospective studies in highly selected patients. The aim of this prospective, multicentre study was to assess treatment and outcomes of malignant pNENs in clinical practice.

PATIENTS AND METHODS

Consecutive patients with newly diagnosed, histologically-proven pNENs were included and followed-up for 2 years. Tumours were defined as malignant when nodal or distant metastases were present or invasion of extrapancreatic structures/organs was evident.

RESULTS

A total of 140 patients with malignant pNENs were included. Ninety-eight patients (70.0%) underwent a surgical resection (76 radical and 22 palliative). Other non-surgical treatments were used in 101 patients (72.1%): somatostatin analogues (n = 63), chemotherapy (n = 30), ablative treatments (n = 15) and peptide-receptor radionuclide therapy (n = 14). No relationship was observed between the 2010 WHO classification and type of treatment. A surgical resection was more often performed in incidentally detected tumours located in the pancreas body tail. Two-year progression-free survival was 63.8%: 82% after a radical resection, 44% after a palliative resection and 41% without a resection. A radical resection and Ki67 proliferative index >5% and >10% were the only significant prognostic determinants in multivariate analysis.

CONCLUSIONS

A radical resection is the cornerstone treatment of malignant pNENs and represents, together with Ki67 assessment, the most powerful prognostic factor for 2-year outcomes.

A review of the use of somatostatin analogs in oncology

Somatostatin is a neuropeptide produced by paracrine cells that are located throughout the gastrointestinal tract, lung, and pancreas, and is also found in various locations of the nervous system. It exerts neural control over many physiological functions including inhibition of gastrointestinal endocrine secretion through its receptors. Potent and biologically stable analogs of somatostatin have been developed. These somatostatin analogs show different efficacy on different receptors, and receptors are varyingly concentrated in specific tissues. Antitumor and antisecretory effects of somatostatin analogs in cancer have been shown in several in vivo and in vitro studies. However, these activities have not always yielded into clinically relevant patient outcome benefit. Somatostatin analogs are of clinical benefit in treating symptoms of ectopic hormone secretion (adrenocorticotropic hormone, growth hormone-releasing hormone) in lung cancer, without inducing a significant tumor response. They have also been shown to induce a statistically significant decrease in bone pain and increase in Karnofsky performance status in patients with metastatic prostate cancer. Somatostatin analogs alone or in combination with other agents have only limited antitumoral effect in breast cancer. In gastrointestinal cancers, studies have not shown an objective tumor response to somatostatin analogs except in endocrine tumors of the liver with symptomatic and biochemical improvement. In neuroendocrine tumors of the gastrointestinal system and pancreas, very high symptomatic and biochemical response rates have been achieved with somatostatin analogs. Antiproliferative activity has been clearly shown in metastatic midgut neuroendocrine tumors.

Treatment of liver metastases in patients with digestive neuroendocrine tumors

BACKGROUND

Liver metastases are a strong prognostic indicator in patients with gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs). Therapeutic options for metastatic NETs are expanding and not mutually exclusive.

AIMS

This paper reviews the literature relating to multidisciplinary approach towards GEP-NET metastases, to highlight advances in knowledge regarding these tumors, and to understand the interdisciplinary management of individual patients.

METHODS

A PubMed search was performed for English-language publications from 1995 through 2012. Reference lists from studies selected were manually searched to identify further relevant reports. Manuscripts comparing different therapeutic options and advances for GEP-NET-related liver metastases were selected.

RESULTS

There is considerable controversy regarding the optimal management of GEP-NET metastases. Although radical surgery still remains the gold standard, a variety of other therapeutic options are available for metastatic GEP-NETs, including loco-regional chemotherapy/radiotherapy, radioembolization, systemic peptide receptor radionuclide therapy, biotherapy, and chemotherapy. In selected patients, liver transplantation should also be considered. Systemic somatostatin analogues and/or interferon show anti-proliferative effects, representing an appropriate first-line treatment for most patients. In advanced metastatic NETs, recent options include targeted therapies (i.e., everolimus and sunitinib).

CONCLUSIONS

It is evident that multidisciplinary care and multimodality treatments remain the cornerstone of management of NET patients. Since NETs often show a more indolent behavior compared to other malignancies, physicians should aim to preserve a satisfactory quality of life for the patient by personalizing the therapeutic approach according to the tumor's features and prognostic factors.

Availability of yttrium-90 from strontium-90: a nuclear medicine perspective

Yttrium-90 (T(½) 64.1 hours, E(βmax)=2.28 MeV) is a pure β⁻ particle emitting radionuclide with well-established applications in targeted therapy. There are several advantages of ⁹⁰Y as a therapeutic radionuclide. It has a suitable physical half-life (∼64 hours) and decays to a stable daughter product ⁹⁰Zr by emission of high-energy β⁻ particles. Yttrium has a relatively simple chemistry and its suitability for forming complexes with a variety of chelating agents is well established. The ⁹⁰Sr/⁹⁰Y generator is an ideal source for the long-term continuous availability of no-carrier-added ⁹⁰Y suitable for the preparation of radiopharmaceuticals for radionuclide therapy. The parent radionuclide ⁹⁰Sr, which is a long-lived fission product, is available in large quantities from spent fuel. Several useful technologies have been developed for the preparation of ⁹⁰Sr/⁹⁰Y generators. There are several well-established radiopharmaceuticals based on monoclonal antibodies, peptides, and particulates labeled with ⁹⁰Y, that are in regular use for the treatment of some forms of primary cancers and arthritis. At present, there are no generators for the elution of ⁹⁰Y that can be set up in a hospital radiopharmacy. The radionuclide is procured from manufacturers and the radiopharmaceuticals are formulated on site. This article reviews the development of ⁹⁰Sr/⁹⁰Y generator and the development of ⁹⁰Y radiopharmaceuticals.

Contrast-enhanced ultrasound after devascularisation of neuroendocrine liver metastases: functional and morphological evaluation

OBJECTIVE

To evaluate morphological and perfusion changes in liver metastases of neuroendocrine tumours by contrast-enhanced ultrasound (CEUS) after transarterial embolisation with bead block (TAE) or trans-arterial chemoembolisation with doxorubicin-eluting beads (DEB-TACE).

METHODS

In this retrospective study, seven patients underwent TAE, and ten underwent DEB-TACE using beads of the same size. At 1 day before embolisation, 2 days, 1 month and 3 months after the procedure, a destruction-replenishment study using CEUS was performed with a microbubble-enhancing contrast material on a reference tumour. Relative blood flow (rBF) and relative blood volume (rBV) were obtained from the ratio of values obtained in the tumour and in adjacent liver parenchyma. Morphological parameters such as the tumour's major diameter and the viable tumour's major diameter were also measured. A parameter combining functional and morphological data, the tumour vitality index (TVI), was studied. The Wilcoxon rank-sum test and Fisher's test were used to compare treatment groups.

RESULTS

At 3 months rBF, rBV and TVI were significantly lower (P = 0.005, P = 0.04 and P = 0.03) for the group with doxorubicin. No difference in morphological parameters was found throughout the follow-up.

CONCLUSIONS

One parameter, TVI, could evaluate the morphological and functional response to treatments.

Molecular pathology and genetics of pancreatic endocrine tumours

Pancreatic neuroendocrine tumours (PETs) are the second most frequent pancreatic neoplasms. Their poor chemosensitivity, high rate of metastatic disease and relatively long survival make PETs an ideal field to be explored for novel therapies based on specific molecular changes. PETs are generally sporadic but can also arise within hereditary syndromes, such as multiple endocrine neoplasia type 1, von Hippel-Lindau, neurofibromatosis type 1 and tuberous sclerosis complex, which represent a model for sporadic cases too. Among allelic imbalances, main genomic changes involve gain of 17q, 7q and 20q and loss of 11q, 6q and 11p, which identify regions of putative candidate oncogenes or tumour suppressor genes (TSGs), respectively, sometime with potential prognostic significance. Overexpression of Src-like kinases and cyclin D1 (CCND1) oncogene has been described. As for TSGs, P53 (TP53), DPC4/SMAD4 and RB (RB1) are not implicated in PET tumorigenesis, while for p16INK4a (CDKN2A), TIMP3, RASSF1A and hMLH1, more data are available, suggesting a role for methylation as a silencing mechanism. In the last decade, gene expression profile studies, analysis of microRNAs and, more recently, large-scale mutational analysis have highlighted commonly altered molecular pathways in the pathology of PETs. The roles of the mammalian target of rapamycin pathway, and its connection with Src kinases, and the activity of a number of tyrosine kinase receptors seem to be pivotal, as confirmed by the results of recent clinical trials with targeted agents. Mutations of DAXX and ATRX are common and related to altered telomeres but not to prognosis.