Everolimus for the Treatment of Advanced Pancreatic Neuroendocrine Tumors: Overall Survival and Circulating Biomarkers From the Randomized, Phase III RADIANT-3 Study

Evaluating gastroenteropancreatic neuroendocrine tumors through microRNA sequencing

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) can be challenging to evaluate histologically. MicroRNAs (miRNAs) are small RNA molecules that often are excellent biomarkers due to their abundance, cell-type and disease stage specificity and stability. To evaluate miRNAs as adjunct tissue markers for classifying and grading well-differentiated GEP-NETs, we generated and compared miRNA expression profiles from four pathological types of GEP-NETs. Using quantitative barcoded small RNA sequencing and state-of-the-art sequence annotation, we generated comprehensive miRNA expression profiles from archived pancreatic, ileal, appendiceal and rectal NETs. Following data preprocessing, we randomly assigned sample profiles to discovery (80%) and validation (20%) sets prior to data mining using machine-learning techniques. High expression analyses indicated that miR-375 was the most abundant individual miRNA and miRNA cistron in all samples. Leveraging prior knowledge that GEP-NET behavior is influenced by embryonic derivation, we developed a dual-layer hierarchical classifier for differentiating GEP-NET types. In the first layer, our classifier discriminated midgut (ileum, appendix) from non-midgut (rectum, pancreas) NETs based on miR-615 and -92b expression. In the second layer, our classifier discriminated ileal from appendiceal NETs based on miR-125b, -192 and -149 expression, and rectal from pancreatic NETs based on miR-429 and -487b expression. Our classifier achieved overall accuracies of 98.5% and 94.4% in discovery and validation sets, respectively. We also found provisional evidence that low- and intermediate-grade pancreatic NETs can be discriminated based on miR-328 expression. GEP-NETs can be reliably classified and potentially graded using a limited panel of miRNA markers, complementing morphological and immunohistochemistry-based approaches to histologic evaluation.

Resection of Liver Metastases: A Treatment Provides a Long-Term Survival Benefit for Patients with Advanced Pancreatic Neuroendocrine Tumors: A Systematic Review and Meta-Analysis

Purpose

Nonsurgical therapies, including biotherapy, chemotherapy, and liver-directed therapy, provided a limit survival benefit for PNET patients with hepatic metastases. With the development of liver resection technique, there was a controversy on whether to perform a liver resection for these patients.

Methods

A computerized search was made of the Medline/PubMed, EMbase, Cochrane Library, and SinoMed (CBM) before March 2018. A meta-analysis was performed to investigate the differences in the efficacy of liver resection and nonliver resection treatments based on the evaluation of morbidity, 30-day mortality, symptom relief rate, and 1-, 3-, and 5-year survival. Two investigators reviewed all included articles and extracted the data of them. The meta-analysis was performed via Review Manager 5.3 software.

Results

A total of 13 cohort studies with 1524 patients were included in this meta-analysis. Compared with the nonliver resection group, liver resection group had a longer 1-, 3-, and 5-year survival time and a higher symptom relief with an acceptable mortality and morbidity.

Conclusions

Liver resection is a safe treatment and could significantly prolong the long-term prognosis for highly selected patients with resectable liver metastases from PNET. Further randomized, controlled trials are needed.

Everolimus

Everolimus (RAD001) is an oral protein kinase inhibitor of the mTOR (mammalian target of rapamycin) serine/threonine kinase signal transduction pathway. The mTOR pathway regulates cell growth, proliferation and survival, and is frequently deregulated in cancer.The EMA has approved Everolimus as Afinitor^® for the treatment of hormone receptor-positive, HER2/neu-negative advanced breast cancer, in combination with exemestane, in postmenopausal women without symptomatic visceral disease after recurrence or progression following a nonsteroidal aromatase inhibitor, for the treatment of unresectable or metastatic, well- or moderately differentiated neuroendocrine tumors of pancreatic origin in adults with progressive disease, and for the treatment of unresectable or metastatic, well-differentiated (Grade 1 or Grade 2) nonfunctional neuroendocrine tumors of gastrointestinal or lung origin in adults with progressive disease, and for the treatment of patients with advanced renal cell carcinoma, whose disease has progressed on or after treatment with VEGF-targeted therapy And as Votubia^® for the treatment of adult patients with renal angiomyolipoma associated with tuberous sclerosis complex (TSC), who are at risk of complications (based on factors such as tumor size or presence of aneurysm, or presence of multiple or bilateral tumors) but who do not require immediate surgery, and for the treatment of patients with subependymal giant cell astrocytoma (SEGA) associated with TSC who require therapeutic intervention but are not amenable to surgery, and as an add-on treatment in patients from 2 years of age with seizures related to TSC that have not responded to other treatments ( https://www.novartis.com/news/media-releases/novartis-drug-votubiar-receives-eu-approval-treat-refractory-partial-onset ). The FDA has approved Everolimus as Afinitor^® for the treatment of postmenopausal women with advanced hormone receptor-positive, HER2-negative breast cancer in combination with exemestane, after the failure of treatment with letrozole or anastrozole, for the treatment of adult patients with progressive neuroendocrine tumors of pancreatic origin (PNET) with unresectable, locally advanced or metastatic disease, for the treatment of adult patients with advanced RCC after failure of treatment with sunitinib or sorafenib, for the treatment of adult patients with renal angiomyolipoma and tuberous sclerosis complex (TSC), not requiring immediate surgery. for the treatment of adult and pediatric patients, 3 years of age or older, with SEGA associated with TSC who require therapeutic intervention but are not candidates for curative surgical resection. Everolimus shows promising clinical activity in additional indications. Multiple Phase II and Phase III trials of everolimus alone or in combination and will help to further elucidate the role of mTOR in oncology. For a review on everolimus as immunosuppressant, please consult other sources.

Gastroenteropancreatic Neuroendocrine Tumors

Neuroendocrine tumors (NETs) are heterogeneous malignancies arising from the diffuse neuroendocrine system. They frequently originate in the gastroenteropancreatic (GEP) tract and the bronchopulmonary tree, and their incidence has steadily increased in the last 3 decades. Fundamental biologic and genomic differences underlie the clinical heterogeneity of NETs, and distinct molecular features characterize NETs of different grades and different primary sites. Although surgery remains the cornerstone of treatment for localized tumors, systemic treatment options for patients with metastatic NETs have expanded considerably. Somatostatin analogs have demonstrated both antisecretory and antitumor efficacy. Peptide receptor radionuclide therapy with lutetium-177 dotatate (¹⁷⁷ Lu-DOTATATE) has been approved for advanced GEP-NETs. The antitumor activity of everolimus has been demonstrated across a wide spectrum of NETs, and the antiangiogenic agent sunitinib has been approved for pancreatic NETs (pNETs). Chemotherapy with temozolomide and capecitabine has recently demonstrated an unprecedented prolongation of progression-free survival in a randomized trial of pNETs. Multiple retrospective series have reported the efficacy of liver-directed therapies both for palliating symptoms of hormone excess and for controlling tumor growth. Telotristat, an oral inhibitor of tryptophan hydroxylase, has been shown to reduce diarrhea in patients with carcinoid syndrome. Defining the therapeutic algorithm and identifying biomarkers predictive of response to treatments are among the main priorities for the next decade of research in the NET field.

A systematic review and meta-analysis of gastrointestinal events associated with nonoperative therapies for neuroendocrine tumors

The risk of gastrointestinal (GI) events induced by nonoperative therapies in patients with neuroendocrine tumors (NETs) is unclear. Nonoperative therapies include somatostatin analogs, molecular targeted agents, cytotoxic chemotherapy, interferon-α, and peptide receptor radionuclide therapy. We undertook an up-to-date meta-analysis to determine the incidence and relative risks (RRs) of GI events in NET patients treated with these therapies. MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were searched to identify relevant trials. Eligible trials were selected according to the PRISMA statement. Summary incidence, RR, and 95% CIs were calculated using random- and fixed-effects models. We included 2,890 patients from 17 randomized controlled trials in this meta-analysis. The experimental treatments led to increased incidence and risks of GI events compared to the control treatments (P<0.05). Diarrhea was the most common GI event. The experimental treatments were associated with increased risks of high-grade nausea (RR 2.36; 95% CI 1.05-5.25; P<0.01) and vomiting (RR 1.89; 95% CI 1.04-3.44; P<0.05). In regard to specific therapy regimens, everolimus led to increased risks of diarrhea (RR 2.97; 95% CI 1.83-4.83; P<0.05), vomiting (RR 2.19; 95% CI 1.38-3.48; P<0.05), and anorexia (RR 3.20; 95% CI 1.69-6.06; P<0.05), whereas VEGFR inhibitors led to increased risk of diarrhea (RR 2.12; 95% CI 1.39-3.25; P<0.05). Additionally, GI NETs led to higher risk of GI events than pancreatic NETs. Thus, nonoperative therapies are associated with increased risks of GI events in NET patients, and rigorous management is warranted to minimize the adverse impact on treatment outcomes and to improve quality of life.

Epidemiologic trends in neuroendocrine tumors: An examination of incidence rates and survival of specific patient subgroups over the past 20 years

INTRODUCTION

Neuroendocrine tumors (NETs) represent a small proportion of cancers, but are increasing in incidence due to incidental diagnosis. We examined NET incidence and survival over time in a population-based registry.

MATERIALS/METHODS

We identified all NET cases diagnosed between 1995 and 2014 in the Surveillance, Epidemiology, and End Results database, November 2016 submission. We determined incidence rates and calculated overall and cancer-specific survival curves in different subgroups stratified by grade, stage, and age at diagnosis.

RESULTS

We identified 85,133 patients with a diagnosis of NET between 1995 and 2014. Patients with grade 1, localized NETs had the best median overall survival (233 months, 95% confidence intervals [CI] not estimable) and 5-year cancer-specific survival (97.6%; 95% CI, 97.4%, 97.8%). The median overall survival decreased with age across the entire spectrum of ages, with patients >70 years having a particularly poor prognosis (28.0 months; 95% CI, 26.5, 29.5). Patients >70 years old often had distant (34.3%) or grade 3 disease (40.8%), but even elderly patients with lower grade and/or stage disease had worse median overall survival compared with younger subjects.

CONCLUSIONS

Age appears to be associated with a worse prognosis independent of NET stage, and grade at the time of diagnosis. Patients with grade 1, localized NETs have an excellent long-term prognosis. Further research is warranted on reducing intensity of surveillance in these patients.

Safety and efficacy of combining capecitabine and temozolomide (CAPTEM) to treat advanced neuroendocrine neoplasms: A meta-analysis

Retrospective studies have suggested that capecitabine combined with temozolomide (CAPTEM) is effective for treating patients with advanced neuroendocrine neoplasms (NENs); however, the efficacy and safety of this regimen needs to be verified by high-quality evidence or results of randomized controlled trials.We carried out a meta-analysis to evaluate the safety and effectiveness of a CAPTEM protocol for patients with advanced NENs. Systematic electronic literature searches were conducted using PubMed, EMBASE, and the Cochrane Library, and among meeting abstracts of the American Society of Clinical Oncology, European Society for Medical Oncology, European Neuroendocrine Tumor Society, and North American Neuroendocrine Tumor Society, up to June 30, 2017. We selected studies describing CAPTEM regimens for treating advanced NENs and reported on tumor response and/or toxicities according to clear World Health Organization (WHO) grading of patients. Three reviewers independently and repeatedly identified studies, extracted data, and assessed the quality of the literature. A single-proportion meta-analysis was applied to included articles.Fifteen studies with a total of 384 individuals were included. Medium overall survival in most studies was more than 12 months, whereas medium progression-free survival was similar or slightly higher than that in studies using other treatment regimes. Disease control rate of CAPTEM administration for patients with NENs was 72.89% (95% confidence interval, 64.04-81.73%; I = 82.4%; P < .01). WHO grade 3 to 4 toxicities, such as thrombocytopenia (3.36%), neutropenia (0.69%), lymphopenia (0.65%), anemia (0.59%), mucositis (0.57%), fatigue (0.54%), diarrhea (0.49%), nausea (0.39%), and transaminase elevation (0.13%) were reported in the trials included.CAPTEM is effective and relatively safe for treating patients with advanced NENs.

The role of GSK3 and its reversal with GSK3 antagonism in everolimus resistance

Pancreatic neuroendocrine tumors (panNETs) are often inoperable at diagnosis. The mTORC1 inhibitor everolimus has been approved for the treatment of advanced NETs. However, the regular development of resistance to everolimus limits its clinical efficacy. We established two independent everolimus-resistant panNET (BON1) cell lines (BON1 RR1, BON1 RR2) to find potential mechanisms of resistance. After 24 weeks of permanent exposure to 10 nM everolimus, BON1 RR1 and BON1 RR2 showed stable resistance with cellular survival rates of 96.70% (IC₅₀ = 5200 nM) and 92.30% (IC₅₀ = 2500 nM), respectively. The control cell line showed sensitivity to 10 nM everolimus with cellular survival declining to 54.70% (IC₅₀ = 34 nM). Both resistant cell lines did not regain sensitivity over time and showed persistent stable resistance after a drug holiday of 13 weeks. The mechanisms of resistance in our cell line model included morphological adaptations, G1 cell cycle arrest associated with reduced CDK1(cdc2) expression and decreased autophagy. Cellular migration potential was increased and indirectly linked to c-Met activation. GSK3 was over-activated in association with reduced baseline IRS-1 protein levels. Specific GSK3 inhibition strongly decreased BON1 RR1/RR2 cell survival. The combination of everolimus with the PI3Kα inhibitor BYL719 re-established everolimus sensitivity through GSK3 inhibition and restoration of autophagy. We suggest that GSK3 over-activation combined with decreased baseline IRS-1 protein levels and decreased autophagy may be a crucial feature of everolimus resistance, and hence, a possible therapeutic target.

Oral stomatitis and mTOR inhibitors: A review of current evidence in 20,915 patients

BACKGROUND

Traditional treatment of malignancies with chemotherapeutic agents is often affected by the damage inflicted on non-cancerous cells. Toxicities of the oral cavity, such as mucositis and stomatitis, are some of the most significant and unavoidable toxicities associated with anti-cancer therapies. For such reason, in the last decades, newer targeted agents have been developed aiming to decrease the rates of side effects on healthy cells. Unfortunately, targeted anti-cancer therapies also showed significant rate of toxicity on healthy tissues. mTOR inhibitors showed some adverse events, such as hyperglycemia, hyperlipidemia, hypophosphatemia, hematologic toxicities, and mucocutaneous eruption, but the most important are still stomatitis and skin rash, often reported as dose-limiting side effects.

PATIENTS AND METHODS

A search of the literature was performed by authors on the PubMed online database using the following key words: "sirolimus" OR "everolimus" OR "temsirolimus" OR "deforolimus" OR "ridaforolimus" combined with the Boolean operator AND with the terms: "stomatitis" OR "mucositis" OR "oral pain." Titles and abstracts of 382 potentially relevant studies were screened; of these, 114 studies were excluded because they did not report the inclusion criteria. In the second round, 268 studies were read full-text, but only 135 reported the inclusion criteria and were included for data extraction. Of the included studies, 95 referred to everolimus use, 16 to ridaforolimus, and 26 to temsirolimus (two studies referred to both everolimus and temsirolimus).

RESULTS

The incidence rate of stomatitis according to the agent used was 25.07% (3,959/15,787) for everolimus, 27.02% (724/2,679) for temsirolimus, and 54.76% (598/1,092) for ridaforolimus. All the three agents analyzed showed high rates of low-grade stomatitis (G1-G2), while the onset of severe stomatitis (G3-G4) was rare.

CONCLUSIONS

Analysis of the reports with patients treated with everolimus, temsirolimus, and ridaforolimus showed a clear prevalence of stomatitis grade 1 or 2. These data differ from that of patients treated with conventional chemotherapy in which mucositis is predominantly of grade 3 or 4.

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.

Consensus guidelines for the use and interpretation of angiogenesis assays

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

Chromogranin A: From Laboratory to Clinical Aspects of Patients with Neuroendocrine Tumors

Background. Neuroendocrine tumors (NETs) are characterized by having behavior and prognosis that depend upon tumor histology, primary site, staging, and proliferative index. The symptoms associated with carcinoid syndrome and vasoactive intestinal peptide tumors are treated with octreotide acetate. The PROMID trial assesses the effect of octreotide LAR on the tumor growth in patients with well-differentiated metastatic midgut NETs. The CLARINET trial evaluates the effects of lanreotide in patients with nonfunctional, well-, or moderately differentiated metastatic enteropancreatic NETs. Everolimus has been approved for the treatment of advanced pancreatic NETs (pNETs) based on positive PFS effects, obtained in the treated group. Sunitinib is approved for the treatment of patients with progressive gastrointestinal stromal tumor or intolerance to imatinib, because a randomized study demonstrated that it improves PFS and overall survival in patients with advanced well-differentiated pNETs. In a phase II trial, pasireotide shows efficacy and tolerability in the treatment of patients with advanced NETs, whose symptoms of carcinoid syndrome were resistant to octreotide LAR. An open-label, phase II trial assesses the clinical activity of long-acting repeatable pasireotide in treatment-naive patients with metastatic grade 1 or 2 NETs. Even if the growth of the neoplasm was significantly inhibited, it is still unclear whether its antiproliferative action is greater than that of octreotide and lanreotide. Because new therapeutic options are needed to counter the natural behavior of neuroendocrine tumors, it would also be useful to have a biochemical marker that can be addressed better in the management of these patients. Chromogranin A is currently the most useful biomarker to establish diagnosis and has some utility in predicting disease recurrence, outcome, and efficacy of therapy.

A classification prognostic score to predict OS in stage IV well-differentiated neuroendocrine tumors

No validated prognostic tool is available for predicting overall survival (OS) of patients with well-differentiated neuroendocrine tumors (WDNETs). This study, conducted in three independent cohorts of patients from five different European countries, aimed to develop and validate a classification prognostic score for OS in patients with stage IV WDNETs. We retrospectively collected data on 1387 patients: (i) patients treated at the Istituto Nazionale Tumori (Milan, Italy; n = 515); (ii) European cohort of rare NET patients included in the European RARECAREnet database (n = 457); (iii) Italian multicentric cohort of pancreatic NET (pNETs) patients treated at 24 Italian institutions (n = 415). The score was developed using data from patients included in cohort (i) (training set); external validation was performed by applying the score to the data of the two independent cohorts (ii) and (iii) evaluating both calibration and discriminative ability (Harrell C statistic). We used data on age, primary tumor site, metastasis (synchronous vs metachronous), Ki-67, functional status and primary surgery to build the score, which was developed for classifying patients into three groups with differential 10-year OS: (I) favorable risk group: 10-year OS ≥70%; (II) intermediate risk group: 30% ≤ 10-year OS < 70%; (III) poor risk group: 10-year OS <30%. The Harrell C statistic was 0.661 in the training set, and 0.626 and 0.601 in the RARECAREnet and Italian multicentric validation sets, respectively. In conclusion, based on the analysis of three 'field-practice' cohorts collected in different settings, we defined and validated a prognostic score to classify patients into three groups with different long-term prognoses.

Everolimus in the treatment of neuroendocrine tumors: efficacy, side-effects, resistance, and factors affecting its place in the treatment sequence

INTRODUCTION

Since the initial approval of everolimus in 2011, there have been a number of important changes in therapeutic/diagnostic modalities as well as classification/staging systems of neuroendocrine tumors (NETs), which can significantly impact the use of everolimus in patients with advanced NETs. Areas covered: The efficacy of everolimus monotherapy and combination therapy demonstrated in clinical studies involving patients with advanced NETs are reviewed. Several factors affecting everolimus use are described including: the development and routine use of NET classification/staging systems; widespread use of molecular imaging modalities; side effects; drug resistance; and the availability of other treatment options. Furthermore, the current position of everolimus in the treatment approach is discussed, taking into account the recommendations from the recent guidelines. Expert opinion: Although everolimus demonstrated its high efficacy and tolerability in the RADIANT trials and other clinical studies, there still remain a number of controversies related to everolimus treatment in the management of NETs. The synergistic anti-growth effect of other agents in combination with everolimus or its effect on overall survival have not been established. The appropriate order of the use of everolimus in the treatment of advanced NETs still remains unclear, which needs to be defined in further studies and will be addressed in the new guidelines.

Molecular profiling of pancreatic neuroendocrine tumors (pNETS) and the clinical potential

Pancreatic neuroendocrine tumors (pNETs) represent a small part of pancreatic neoplasms, and the knowledge about their indolent clinical course remains a subject of investigation. They occur sporadically or as part of familial cancer syndromes and are classified by WHO in 3 categories. There is ongoing research to understand their molecular profiling and leading mutations. Areas covered: The aim of this review is to clarify the overall aspects of tumorigenesis, to expose the latest developments in understanding the course of the disease and the possible therapeutic implications of these. The review also discusses functional and non-functional pNETs and associated inherited syndromes as well as pNET molecular profiling and its possible guidance in the use of targeted therapy. Expert commentary: In the next decade, a more extensive application of new technologies will help improve quality of life and survival, individualizing treatment protocols and identifying which therapeutic strategy is more suitable for each kind of NET.

Advanced neuroendocrine tumours of the small intestine and pancreas: clinical developments, controversies, and future strategies

In this Review, we discuss clinical developments and controversies in the treatment of neuroendocrine tumours (NETs) that are relevant for clinicians and clinical researchers. We describe advances in genetics, blood-based biomarkers, functional imaging, and systemic therapy of advanced NETs and discuss results of recent phase 3 studies, systemic treatment of advanced disease with peptide receptor radionuclide therapy, biotherapy, chemotherapy, and molecularly targeted therapy, and the potential role of immunotherapy in the treatment of NETs. Suggested treatment algorithms for NETs of ileal or jejunal origin and of pancreatic origin are presented.

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.

Sunitinib shrinks NET-G3 pancreatic neuroendocrine neoplasms

PURPOSE

The 2017 revised World Health Organization classification of pancreatic neuroendocrine neoplasms classified conventional G3 tumors into well-differentiated (NET-G3) and poorly differentiated (NEC-G3) tumors. However, guidelines for selection of drug therapy were not established in the 2017 revision. This study aimed to elucidate the rates of maximum tumor reduction of sunitinib, progression-free survival, and overall survival in the new classification.

METHODS

We investigated the reduction rate over time using computed tomography for 60 patients with unresectable or distant metastatic pancreatic neuroendocrine neoplasms who received 37.5 mg of sunitinib in our department from April 2013 to November 2017.

RESULTS

Of the 60 cases, 42, 10, and 5 were NET-G1/G2, NET-G3, and NEC-G3, respectively. The prognostic factors were analyzed according to clinicopathological factors using the Cox hazard model. The median observation period was 19 months, and the median duration of sunitinib administration was 7 months. The median maximum reduction rate of sunitinib was 18.3%. Tumor response was classified according to the Response Evaluation Criteria in Solid Tumors: 20 cases (33.3%) showed partial response, 29 cases (48.3%) showed stable disease, and 11 cases (18.3%) showed progressive disease. In a multivariate analysis of factors contributing to progression-free survival from the start of sunitinib administration, only histologically poor differentiation was a significant factor (p = 0.010). Progression-free survival and overall survival were significantly better in patients with NET-G3 than that in patients with NEC-G3 (p = 0.005, p = 0.012), while it was not different between those with NET-G3 and those with NET-G1/2.

CONCLUSION

Our results indicate that sunitinib is as effective for NET-G3 as for NET-G1/2.

The Role of mTOR in Neuroendocrine Tumors: Future Cornerstone of a Winning Strategy?

The mechanistic target of rapamycin (mTOR) is part of the phosphoinositide-3-kinase (PI3K)/protein kinase B (AkT)/mTOR pathway and owes its name to the inhibitory effect of rapamycin. The mTOR has a central converging role for many cell functions, serving as a sensor for extracellular signals from energy status and nutrients availability, growth factors, oxygen and stress. Thus, it also modulates switch to anabolic processes (protein and lipid synthesis) and autophagy, in order to regulate cell growth and proliferation. Given its functions in the cell, its deregulation is implicated in many human diseases, including cancer. Its predominant role in tumorigenesis and progression of neuroendocrine tumors (NETs), in particular, has been demonstrated in preclinical studies and late clinical trials. mTOR inhibition by everolimus is an established therapeutic target in NETs, but there are no identified predictive or prognostic factors. This review is focused on the role of mTOR and everolimus in NETs, from preclinical studies to major clinical trials, and future perspectives involving mTOR in the treatment of NETs.

Phase 1b study of pasireotide, everolimus, and selective internal radioembolization therapy for unresectable neuroendocrine tumors with hepatic metastases

BACKGROUND

Neuroendocrine tumors (NETs) metastasize to the liver. Everolimus and selective internal radioembolization (SIRT) are approved treatments. Pasireotide is a somatostatin analogue with an affinity for somatostatin receptors 1, 2, 3, and 5. Everolimus and pasireotide may potentiate SIRT radiosensitization and inhibit rebound angiogenesis. This study evaluated the safety of pasireotide, everolimus, and SIRT.

METHODS

This 3 + 3 phase 1 trial evaluated 3 dose levels of everolimus (2.5, 5, and 10 mg/day), pasireotide (600 μg twice daily), and SIRT (SIR-Spheres dose on days 9 and 37). Eligibility criteria included well or moderately differentiated NETs, bilobar liver metastases, and progression on long-acting octreotide. Toxicities and responses were evaluated with the Common Terminology Criteria for Adverse Events and the Response Evaluation Criteria in Solid Tumors (version 1.1). Dose-limiting toxicities (DLTs) were defined in the first 28 days. Correlative markers-angiopoietin 1, angiopoietin 2, basic fibroblast growth factor, collagen V, insulin-like growth factor binding protein 1, insulin-like growth factor binding protein 1, interleukin 8, M30, M65, placenta growth factor, and vascular endothelial growth factor receptor 2-were assessed. The Norfolk Quality of Life-Neuroendocrine Tumor Questionnaire was used to assess the quality of life (QOL).

RESULTS

Thirteen patients were enrolled; 1 was not evaluable for the primary endpoint. Eleven patients had well-differentiated tumors. The primary sites included small bowel (4), pancreas (3), lung (2), colon (1), gastric (1), and unknown primary (2) were unknown. Four had liver-only disease; 12 completed the planned treatment. No DLTs were observed. There was no treatment-related mortality. The most common toxicity was hyperglycemia. Clinically significant liver toxicity was not observed. One patient had liver progression. QOL improved on treatment. The median progression-free survival and overall survival were 18.6 and 46.3 months, respectively.

CONCLUSIONS

The recommended phase 2 dose of everolimus is 10 mg daily in combination with pasireotide and SIRT. The regimen is well tolerated. Preliminary activity appears promising. Cancer 2018;124:1992-2000. © 2018 American Cancer Society.

Results and adverse events of personalized peptide receptor radionuclide therapy with 90Yttrium and 177Lutetium in 1048 patients with neuroendocrine neoplasms

Introduction

Peptide receptor radionuclide therapy (PRRT) of patients with somatostatin receptor expressing neuroendocrine neoplasms has shown promising results in clinical trials and a recently published phase III study.

Methods

In our center, 2294 patients were screened between 2004 and 2014 by ⁶⁸Ga somatostatin receptor (SSTR) PET/CT. Intention to treat analysis included 1048 patients, who received at least one cycle of ⁹⁰Yttrium or ¹⁷⁷Lutetium-based PRRT. Progression free survival was determined by ⁶⁸Ga SSTR-PET/CT and EORTC response criteria. Adverse events were determined by CTCAE criteria.

Results

Overall survival (95% confidence interval) of all patients was 51 months (47.0-54.9) and differed significantly according to radionuclide, grading, previous therapies, primary site and functionality. Progression free survival (based on PET/CT) of all patients was 19 months (16.9-21), which was significantly influenced by radionuclide, grading, and origin of neuroendocrine neoplasm. Progression free survival after initial progression and first and second resumption of PRRT after therapy-free intervals of more than 6 months were 11 months (9.4-12.5) and 8 months (6.4-9.5), respectively. Myelodysplastic syndrome or leukemia developed in 22 patients (2.1%) and 5 patients required hemodialysis after treatment, other adverse events were rare.

Conclusion

PRRT is effective and overall survival is favorable in patients with neuroendocrine neoplasms depending on the radionuclide used for therapy, grading and origin of the neuroendocrine neoplasm which is not exactly mirrored in progression free survival as determined by highly sensitive ⁶⁸Ga somatostatin receptor PET/CT using EORTC criteria for determining response to therapy.

Clinical benefit of systemic treatment in patients with advanced pancreatic and gastrointestinal neuroendocrine tumours according to ESMO-MCBS and ASCO framework

BACKGROUND

Assessment of clinical benefit of systemic treatments of rare diseases including gastroenteropancreatic neuroendocrine tumours (GEP-NET) is challenging. Recently several tools have been developed to grade the clinical benefit of cancer drugs. The European Society for Medical Oncology (ESMO) has developed the ESMO Magnitude of Clinical Benefit Scale (ESMO-MCBS). The American Society of Clinical Oncology (ASCO) has developed and revised the ASCO framework consisting of the Net Health Benefit (NHB) score juxtaposed against the costs of the treatment. In this review, we graded systemic treatments for GEP-NET patients with both frameworks.

METHODS

The electronic databases (PubMed and EMBASE) were searched for papers reporting comparative trials, conducted in adult GEP-NET patients in the English language. Papers were assessed according to the ESMO-MCBS and the NHB part of the ASCO revised Framework (NHB-ASCO-F) by four independent assessors, and discrepancies were discussed.

RESULTS

The search yielded 32 trials of which 6 were eligible for grading with the ESMO-MCBS resulting in scores of 2 or 3. Eight trials were eligible for grading with the NHB-ASCO-F, resulting in scores between 37.6 and 57.4. Trials that were not primary assessable by the tools were analysed separately. Consensus between assessors was reached in 68% of trials with the ESMO-MCBS and in 23% of trials with the NHB-ASCO-F.

CONCLUSION

The currently used systemic treatments for GEP-NET patients had low scores according to the NHB-ASCO-F and none could be graded as meaningful clinical beneficial according to the ESMO-MCBS. Despite the low incidence, the heterogeneous patient population and relatively long natural course of NET, future studies on new treatment modalities should aim for high clinical benefit outcomes.

Advances and Current Concepts in the Medical Management of Gastroenteropancreatic Neuroendocrine Neoplasms

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are rare and heterogeneous group of tumors presenting as localised or metastatic disease and in a subset with distinct clinical syndromes. Treatment is aimed at controlling the functional syndrome, eradicating the tumor, and/or preventing further tumor growth. Surgery is the treatment of choice in removing the primary tumor and/or reducing tumor burden but cannot be applied to all patients. Somatostatin analogs (SS-analogs) obtain control of functional syndromes in the majority of GEP-neuroendocrine tumors (NETs); phase III trials have shown that SS-analogs can be used as first-line antiproliferative treatment in patients with slow-growing GEP-NETs. The role of the recently approved serotonin inhibitor, telotristat ethyl, and gastrin receptor antagonist, netazepide, is evolving. Streptozotocin-based chemotherapy has been used for inoperable or progressing pancreatic NENs but the orally administered combination of capecitabine/temozolomide is becoming more popular due to its better tolerability and potential effect in other GEP-NENs. Phase III trials have shown efficacy of molecular targeted therapies in GEP-NETs and of radionuclide treatment in patients with midgut carcinoid tumors expressing somatostatin receptors. Most patients will develop disease progression necessitating further therapeutic options. A combination of currently available treatments along with the molecular signature of each tumor will guide future treatment.

Prognostic and predictive role of the PI3K-AKT-mTOR pathway in neuroendocrine neoplasms

Neuroendocrine neoplasms (NENs) are considered a heterogeneous and rare entity. Its natural history is influenced by multiple clinicopathological characteristics, which guide the management of these patients. The development of molecular biology reveals that the PI3K-AKT-mTOR pathway plays a relevant role in tumorigenesis and progression of NENs. Mammalian target of rapamycin (mTOR) inhibitors, targeted agents that block this pathway, has improved outcomes in neuroendocrine tumors (NETs). Different therapeutic approaches, such as somatostatin analogs, chemotherapy, peptide receptor radionuclide therapy, and targeted agents, have shown benefits in the treatment of NETs. However, there are not any established prognostic or predictive biomarkers to select the best therapy option to individualize treatment. Although a relation between alterations in the PI3K-AKT-mTOR pathway and clinical outcomes has not been found, these anomalies are considered attractive biomarkers. Additional molecular analysis should be integrated in future clinical trials' design to identify potential predictive or prognostic biomarkers.

Treatment challenges in and outside a specialist network setting: Pancreatic neuroendocrine tumours

Pancreatic Neuroendocrine Neoplasms comprise a group of rare tumours with special biology, an often indolent behaviour and particular diagnostic and therapeutic requirements. The specialized biochemical tests and radiological investigations, the complexity of surgical options and the variety of medical treatments that require individual tailoring, mandate a multidisciplinary approach that can be optimally achieved through an organized network. The present study describes currents concepts in the management of these tumours as well as an insight into the challenges of delivering the pathway in and outside a Network.

Progression-free survival as a surrogate endpoint in advanced neuroendocrine neoplasms

In oncology clinical trials, overall survival (OS) is considered the gold standard outcome measure. In phase III trials for neuroendocrine neoplasms (NENs), however, progression-free survival (PFS) is more frequently used, as NENs are relatively rare and indolent neoplasms. But this surrogacy of PFS for OS has never been systematically validated. We, therefore, performed a literature-based analysis of phase II and III trials for NENs to evaluate the correlation between PFS and OS in NENs treated with medical treatment. We identified phase II and III clinical trials of medical treatment for advanced NENs based on a systematic electronic search using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. A total of 20 trials were identified, and 2530 patients and 30 treatment arms were included in the analysis. There was a statistically significant relationship between PFS and OS (r_s , 0.587; 95% confidence interval, 0.249-0.925). Conversely, the objective response rate was not significantly correlated with OS. The results of subgroup analyses indicated that the correlation between PFS and OS was higher for study arms that prohibited concomitant therapy with somatostatin analogues than for those that permitted it. The results of the present analysis indicate that PFS is significantly correlated with OS, and suggest that PFS is an acceptable surrogate for OS in clinical trials for NENs.

Treatment Strategies for Metastatic Neuroendocrine Tumors of the Gastrointestinal Tract

OPINION STATEMENT

The therapeutic landscape of gastroenteropancreatic-neuroendocrine tumors (GEP-NETs) has evolved significantly in recent years. Current and emerging treatment options include somatostatin analogs, radiolabeled somatostatin analogs, the mTOR inhibitor everolimus, and the tyrosine kinase inhibitor sunitinib. Although high-quality data from phase III trials are lacking, cytotoxic agents are commonly used for the treatment of poorly differentiated neuroendocrine carcinomas and well-differentiated NETs originating in the pancreas. Hepatic-directed therapies are recommended for patients with slow-growing, liver-predominant disease but have never been compared to systemic agents. Telotristat ethyl, a novel serotonin synthesis inhibitor, has recently demonstrated efficacy in palliating diarrhea in patients with poorly controlled carcinoid syndrome. In the absence of definite predictive biomarkers, therapeutic decisions in most cases rely on clinical and pathological criteria. However, navigating the current therapeutic algorithm may be challenging, and future trials need to address several important questions: what is the best sequence of treatment? Is there a role for combination therapies in GEP-NETs? Are neoadjuvant, adjuvant, or maintenance strategies safe and effective? Do all NET patients require active treatment? What new molecular targets can be clinically exploited? A tight integration between basic and clinical research is needed to further advance the field of NETs.

Do patient access schemes for high-cost cancer drugs deliver value to society?-lessons from the NHS Cancer Drugs Fund

BACKGROUND

The NHS Cancer Drugs Fund (CDF) was established in 2010 to reduce delays and improve access to cancer drugs, including those that had been previously appraised but not approved by NICE (National Institute for Health and Care Excellence). After 1.3 billion GBP expenditure, a UK parliamentary review in 2016 rationalized the CDF back into NICE.

METHODS

This paper analyses the potential value delivered by the CDF according to six value criteria. This includes validated clinical benefits scales, cost-effectiveness criteria as defined by NICE and an assessment of real-world data. The analysis focuses on 29 cancer drugs approved for 47 indications that could be prescribed through the CDF in January 2015.

RESULTS

Of the 47 CDF approved indications, only 18 (38%) reported a statistically significant OS benefit, with an overall median survival of 3.1 months (1.4-15.7 months). When assessed according to clinical benefit scales, only 23 (48%) and 9 (18%) of the 47 drug indications met ASCO and ESMO criteria, respectively. NICE had previously rejected 26 (55%) of the CDF approved indications because they did not meet cost-effectiveness thresholds. Four drugs-bevacizumab, cetuximab, everolimus and lapatinib-represented the bulk of CDF applications and were approved for a total of 18 separate indications. Thirteen of these indications were subsequently delisted by the CDF in January 2015 due to insufficient evidence for clinical benefit-data which were unchanged since their initial approval.

CONCLUSIONS

We conclude the CDF has not delivered meaningful value to patients or society. There is no empirical evidence to support a 'drug only' ring fenced cancer fund relative to concomitant investments in other cancer domains such as surgery and radiotherapy, or other noncancer medicines. Reimbursement decisions for all drugs and interventions within cancer care should be made through appropriate health technology appraisal processes.

The European Society for Medical Oncology 'Magnitude of Clinical Benefit Scale' field-tested in infrequent tumour entities: an extended analysis of its feasibility at the Medical University of Vienna

Background

The European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS) is a new tool to quantify the clinical benefit that may be anticipated from a novel anticancer treatment. We present here an analysis on the feasibility of the ESMO-MCBS in less frequent tumour entities.

Methods

This study evaluates the practicability of the ESMO-MCBS for metastatic neuroendocrine tumours (NETs), soft tissue sarcomas, glioblastoma, thyroid cancer, pancreatic cancer, head/neck cancer, urothelial cancer and ovarian cancer at the Medical University Vienna. A three-step approach including data acquisition, assessment of ESMO-MCBS scores and evaluation of results with a focus on clinical feasibility was applied.

Results

In NET and thyroid cancer, all analysed trials were very comparable in design and efficacy, and the ESMO-MCBS scores appeared to be consistent with the clinical benefit seen in practice. For pancreatic cancer, it was more difficult to compare first-line trials due to diverging populations included in the respective studies. Concerning soft tissue sarcomas, the ESMO-MCBS was applicable for gastrointestinal stromal tumours(GIST) and ‘non-GIST’ soft tissue sarcoma with respect to data deriving from randomised studies. However, due to the heterogeneity of the disease itself and a limited number of controlled trials, limitations are noted. In ovarian cancer, the ESMO-MCBS supported the use of bevacizumab in high-risk patients. To date, there are only limited data for glioblastoma, head/neck cancer and urothelial cancer but whenever randomised trials were available, the ESMO-MCBS rating supported clinical decisions. Interestingly, nivolumab for salvage treatment of head/neck cancer rated extremely high.

Conclusion

The ESMO-MCBS scores supported our common treatment strategies and highlight the potential of new immunomodulatory drugs. Our results encourage further development of the ESMO-MCBS.

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.

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.

Carcinoid heart disease: a guide for screening and timing of surgical intervention

The cardiac manifestations of a neuroendocrine tumour are referred to as carcinoid heart disease (CaHD) and are associated with a poor prognosis. Surgical intervention is the only proven therapeutic option and may prolong survival and quality of life. No consensus has been reached internationally with regard to screening for CaHD and the optimal timing for surgery. Although limited evidence is available on this matter, a trend towards early surgery and subsequent reduced mortality has been observed. In this review we provide an overview of the current understanding and propose a protocol to guide cardiologists in the screening for CaHD and the timing of referral to a specialised surgical centre.

Revised nodal stage for pancreatic neuroendocrine tumors

BACKGROUND

Previously we have proposed a modified European Neuroendocrine Tumor Society (mENETS) staging system for pNETs, which is more suitable than either the American Joint Committee on Cancer (AJCC) or the European Neuroendocrine Tumor Society (ENETS) systems. However, it is necessary to revise the nodal stage of the mENETS system for the under representation of stage III diseases.

METHODS

Nodal substages of the upper gastrointestinal organs (N0: 0 node, N1: 1-2 nodes; N2: ≥3 nodes) or the lower gastrointestinal organs (0: 0 node, N1: 1-3 nodes, and N2:≥ 4 nodes) were incorporated into the mENETS system and evaluated using the Surveillance, Epidemiology, and End Results (SEER) registry series.

RESULTS

The mENETS classification with the upper gastrointestinal N-stage revision (stage III, 17.1%) had better proportional distribution than the mENETS classification (stage III, 8.7%) or the lower gastrointestinal N-stage revision (stage III, 14.5%). N-stage revision (N0: 0 node, N1: 1-2 nodes; N2: ≥3 nodes) was incorporated in the mENETS staging definition for further analysis. Survival curves were well separated by nodal substages. HRs of stage IIA (T3N0M0) and IIB (T1-3N1M0) of the mENETS classification with N-stage revision were similar, indicating these two substages should be attributed to stage II. Survival curves were well separated by stage using the mENETS classification with N-stage revision.

CONCLUSIONS

The mENETS classification with N-stage revision (N0: 0 node, N1: 1-2 nodes; N2: ≥3 nodes) had better prognostic value and proportional distribution than the mENETS classification for pNETs and can be used in clinical practice.

The MTH1 inhibitor TH588 demonstrates anti-tumoral effects alone and in combination with everolimus, 5-FU and gamma-irradiation in neuroendocrine tumor cells

Modulation of the redox system in cancer cells has been considered a promising target for anti-cancer therapy. The novel MTH1 inhibitor TH588 proved tremendous potential in terms of cancer cell eradication, yet its specificity has been questioned by recent reports, indicating that TH588 may also induce cancer cell death by alternative mechanisms than MTH1 inhibition. Here we used a panel of heterogeneous neuroendocrine tumor cells in order to assess cellular mechanisms and molecular signaling pathways implicated in the effects of TH588 alone as well as dual-targeting approaches combining TH588 with everolimus, cytotoxic 5-fluorouracil or γ-irradiation. Our results reflect that TH588 alone efficiently decreased the survival of neuroendocrine cancer cells by PI3K-Akt-mTOR axis downregulation, increased apoptosis and oxidative stress. However, in the dual-targeting approaches cell survival was further decreased due to an even stronger downregulation of the PI3K-Akt-mTOR axis and augmentation of apoptosis but not oxidative stress. Furthermore, we could attribute TH588 chemo- and radio-sensitizing properties. Collectively our data not only provide insights into how TH588 exactly kills cancer cells but also depict novel perspectives for combinatorial treatment approaches encompassing TH588.

Critical focus on mechanisms of resistance and toxicity of m-TOR inhibitors in pancreatic neuroendocrine tumors

Pancreatic neuroendocrine tumors (pNETs) are rare neoplasms representing less than 2% of all pancreatic malignancies. The PI3K-AKT-mTOR pathway is often deregulated in pNETs and seems to play a key role in tumorigenesis. Everolimus, an inhibitor of the mTOR pathway, has demonstrated efficacy in the treatment of pNETs. Nevertheless de novo or acquired drug resistance is responsible for disease progression and represents a major obstacle to overcome by clinicians. Blocking the PI3K/AKT/mTOR pathway may cover the supposed main mechanisms of resistance to everolimus. Therefore, BEZ-235, a potent oral dual PI3K/mTOR inhibitor was investigated in clinical trials. Globally more than 250 patients with different types of solid tumors were treated. Two studies were conducted in pNETs with BEZ-235 as single agent. The former was a phase 2 trial conducted in pNETs resistant to everolimus while the latter a randomized trial comparing everolimus and BEZ-235. Unfortunately, both the studies disappointed the expectations and were prematurely halted mainly due to severe toxicity. On this basis we reviewed m-TOR inhibitors in pNETs, focusing on their mechanisms of resistance and toxicity.

Pancreatic neuroendocrine tumors: the basics, the gray zone, and the target

Pancreatic neuroendocrine tumors (PanNETs) manifest with a range of symptoms and pose a therapeutic challenge. A team approach, in which many specialists come together, is necessary in the quest for the best patient-tailored treatment. Disciplines such as oncology, surgery, basic science, endocrinology, radiology, and nuclear medicine need to work side by side, equally contributing to patient care and to advancing our better understanding of this fascinating disease.

Pancreatic neuroendocrine tumors

Pancreatic neuroendocrine neoplasms (pNENs) are a heterogeneous group of tumors including well differentiated pancreatic neuroendocrine tumors (pNETs) and neuroendocrine carcinomas (pNECs). The incidence of pNENs has increased over the past few decades. Although, the understanding and interest for this tumor have also increased significantly, the debate about classification and diagnosis continues. Although the primary treatment for pNENs is surgical resection, there is still a lack of effective therapeutic options for patients with advanced unresectable pNENs. Although many therapeutic methods have proven effective, the choice of treatment and specific programs are still unclear. Our article presents an overview of pNENs, with a focus on their diagnostic work-up, clinical presentation and treatment options.

Sunitinib in pancreatic neuroendocrine tumors: updated progression-free survival and final overall survival from a phase III randomized study

BACKGROUND

In a phase III trial in patients with advanced, well-differentiated, progressive pancreatic neuroendocrine tumors, sunitinib 37.5 mg/day improved investigator-assessed progression-free survival (PFS) versus placebo (11.4 versus 5.5 months; HR, 0.42; P < 0.001). Here, we present PFS using retrospective blinded independent central review (BICR) and final median overall survival (OS), including an assessment highlighting the impact of patient crossover from placebo to sunitinib.

PATIENTS AND METHODS

In this randomized, double-blind, placebo-controlled study, cross-sectional imaging from patients was evaluated retrospectively by blinded third-party radiologists using a two-reader, two-time-point lock, followed by a sequential locked-read, batch-mode paradigm. OS was summarized using the Kaplan-Meier method and Cox proportional hazards model. Crossover-adjusted OS effect was derived using rank-preserving structural failure time (RPSFT) analyses.

RESULTS

Of 171 randomized patients (sunitinib, n = 86; placebo, n = 85), 160 (94%) had complete scan sets/time points. By BICR, median (95% confidence interval [CI]) PFS was 12.6 (11.1-20.6) months for sunitinib and 5.8 (3.8-7.2) months for placebo (HR, 0.32; 95% CI 0.18-0.55; P = 0.000015). Five years after study closure, median (95% CI) OS was 38.6 (25.6-56.4) months for sunitinib and 29.1 (16.4-36.8) months for placebo (HR, 0.73; 95% CI 0.50-1.06; P = 0.094), with 69% of placebo patients having crossed over to sunitinib. RPSFT analysis confirmed an OS benefit for sunitinib.

CONCLUSIONS

BICR confirmed the doubling of PFS with sunitinib compared with placebo. Although the observed median OS improved by nearly 10 months, the effect estimate did not reach statistical significance, potentially due to crossover from placebo to sunitinib.

TRIAL REGISTRATION NUMBER

NCT00428597.

Radionuclides in oncology clinical practice – review of the literature

Radionuclide therapy is a promising type of targeted therapy for cancer and its use is becoming more common in several types of malignant tumors.