OBJECTIVE

Efficacy of targeted agents, such as everolimus and sunitinib, has been demonstrated in prospective trials on patients with gastroenteropancreatic neuroendocrine tumors (GEP-NETs). Considering the heterogeneous clinicopathological characteristics of neuroendocrine tumors (NETs), evaluation of treatment outcomes in a real-world setting is necessary.

METHODS

Clinical records of 44 patients with GEP-NET who were treated with everolimus or sunitinib between March 2007 and October 2014 were retrospectively reviewed. Considering the distinct characteristics of pancreatic NETs (pNETs) and non-pancreatic gastrointestinal NETs (GI-NETs), efficacy analysis was performed separately.

RESULTS

Pancreas was the most common primary site (n = 28, 64%), followed by rectum (n = 10, 23%) and stomach (n = 3, 7%). Sunitinib and everolimus were administered in 27 (61%) and 17 (39%) patients, respectively. In patients with pNET, median progression-free survival (PFS) with everolimus and sunitinib was 16.6 months (95% CI 8.0-25.1) and 8.0 months (95% CI 0.0-17.4), respectively (p = 0.51). Among non-pancreatic GI-NET patients, median PFS with everolimus and sunitinib was 14.7 months (95% CI 2.4-27.0) and 1.7 months (95% CI 0.5-3.0), respectively (p = 0.001). Compared to patients treated with everolimus, tumor grade 3 (30 vs. 0%) and history of prior cytotoxic chemotherapy (70 vs. 50%) were more common in patients treated with sunitinib.

CONCLUSIONS

Both everolimus and sunitinib were effective in GEP-NET patients. Outcomes of everolimus therapy in GEP-NETs were consistent with those reported elsewhere. Poor efficacy of sunitinib in non-pancreatic GI-NETs may be attributable to the baseline characteristics associated with poor clinical outcomes.

Therapeutic options to inhibit growth of human NETs of the GEP system are limited. Since NSAIDs might provide an antiproliferative treatment alternative with acceptable toxicity, we examined the effects of different NSAIDs on growth and survival in a representative set of human GEP NET cell lines. Growth and apoptosis were determined based on cell numbers, cell-cycle analyses, kinase assays, DNA fragmentation and PARP cleavage. Expression of COX and cell cycle-regulatory molecules was examined by immunoblotting and reporter gene assays. Depending on the drug and cell line investigated, NSAID treatment resulted in profound growth inhibition of GEP NET cells. Growth-inhibitory effects were achieved with either COX-2 selective (NS398) or unselective (indomethacin, sulindac) compounds. Cell-cycle analyses documented a G1 arrest in NSAID-treated GEP NET populations. In addition, 100 microM sulindac or indomethacin induced apoptosis. All 3 COX inhibitors prevented CDK-2 activation. In parallel to the NSAID-mediated reduction of CDK-2 activity, p21(cip-1) promoter activity and cellular p21(cip-1) levels increased and p21(cip-1) was sequestered into CDK-2 complexes. Thus, the G1 arrest likely resulted from p21(cip-1)-dependent inhibition of CDK-2 activity. At therapeutically relevant concentrations, sulindac significantly reduced GEP NET cell numbers, whereas IFN-alpha and octreotide remained ineffective. The extent of growth inhibition in GEP NETs was comparable to the antiproliferative effects of sulindac in established NSAID-sensitive cell models. NSAIDs acted as potent antiproliferative agents in GEP NET cells via G1 cell-cycle arrest and might therefore offer a therapeutic alternative to current treatment modalities.

For the clinical diagnosis and appropriate therapy of patients with cancer of unknown primary (CUP), biopsies of the tumor metastases are generally examined histopathologically and by immunohistochemistry (IHC). Gene expression profiling (GEP) is a new diagnostic technique that might further contribute to tumor specification. Biopsies of 43 CUP cases underwent a retrospective central histopathological and immunohistochemical review and centrally performed GEP using CupPrint(TM). Two samples could not be evaluated by IHC due to small biopsy size or loss of immunoreactivity. One of these and 17 other samples were not suited for GEP due to RNA degradation. In 13 out of the remaining 24 cases (54%), the same primary was proposed by IHC and GEP and was supported by the clinical findings, furthermore leading to the doubtless identification of the primary in four out of these. In seven cases, there was discordance between IHC and GEP, with the clinical picture being more in line with IHC in three and with GEP in four cases. Four cases had to remain undecided because the primary tumors suggested by IHC and GEP were not supported. In conclusion, overlap between IHC and GEP results and the clinical presentation was noted in the majority of those true CUP cases that were evaluable with both techniques. Therefore, GEP can be a complementary diagnostic technique assisting immunohistochemical profiling of cancer biopsies with unknown primary.

Gastro-entero-pancreatic (GEP) and bronchial endocrine tumours have been studied by immunohistochemistry using specific antisera against a variety of hormonal and neuronal peptides. In gastrinomas numerous tumour cells were found to contain GH-like immunoreactivity. These cells were identical with those storing gastrin. Gastrinomas as a rule were extremely heterogeneous containing a variety of minority cell populations, including CCK immunoreactive cells and neurotensin immunoreactive cells. Glucagonoma cells were found to store GIP-like material in addition to glucagon. In some insulinomas calcitonin-like material was encountered in the insulin producing tumour cells. In both glucagonomas and insulinomas other pancreatic endocrine cell types constituted minority cell populations. One intestinal somatostatinoma contained gastrin cells as a minority cell population. Bronchial endocrine tumours contained scattered cells displaying ACTH-like or enkephalin-like immunoreactivity. Two such tumours in addition contained cells displaying neurophysin immunoreactivity.

Somatostatin analogs (SSAs), including lanreotide, play a fundamental role in treatment of neuroendocrine tumors (NETs) of the gastrointestinal tract. SSAs control the clinical symptoms and are the treatment of choice in functioning NETs. Data indicating that SSAs have anti-proliferative activity has mainly come from prospective or retrospective observational studies. A recently published CLARINET study confirmed the anti-proliferative effect of lanreotide in a much broader range of NET patients than previously reported. As a result, it is now possible for clinicians to use lanreotide to treat patients with well-differentiated metastatic grade 1 and grade 2 GEP NETs (i.e., with a Ki-67 proliferative index < 10%) located in the pancreas, small intestine, or of unknown primary location, regardless of the degree of liver involvement. The results of the CLARINET study also challenge the current "wait and watch" strategy for NET treatment. Instead, it is proposed that SSAs are considered at an early stage of NET management, as already suggested by many organizations and scientific societies.

The objective of this work was to establish the quantitative relationship between Lanreotide Autogel® (LAN) on serum chromogranin A (CgA) and progression-free survival (PFS) in patients with nonfunctioning gastroenteropancreatic neuroendocrine tumors (GEP-NETs) through an integrated pharmacokinetic/pharmacodynamic (PK/PD) model. In CLARINET, a phase III, randomized, double-blind, placebo-controlled study, 204 patients received deep subcutaneous injections of LAN 120 mg (n = 101) or placebo (n = 103) every 4 weeks for 96 weeks. Data for 810 LAN and 1298 CgA serum samples (n = 632 placebo and n = 666 LAN) were used to develop a parametric time-to-event model to relate CgA levels and PFS (76 patients experienced disease progression: n = 49 placebo and n = 27 LAN). LAN serum profiles were described by a one-compartment disposition model. Absorption was characterized by two parallel pathways following first- and zero-order kinetics. As PFS data were considered informative dropouts, CgA and PFS responses were modeled jointly. The LAN-induced decrease in CgA levels was described by an inhibitory E MAX model. Patient age and target lesions at baseline were associated with an increment in baseline CgA. Weibull model distribution showed that decreases in CgA from baseline reduced the hazard of disease progression significantly (P < 0.001). Covariates of tumor location in the pancreas and tumor hepatic tumor load were associated with worse prognosis (P < 0.001). We established a semimechanistic PK/PD model to better understand the effect of LAN on a surrogate endpoint (serum CgA) and ultimately the clinical endpoint (PFS) in treatment-naive patients with nonfunctioning GEP-NETs.

The diffuse endocrine system (DES) includes a wide range of secretory cells that may be the source of tumours. Gastroenteropancreatic endocrine (GEP) tumours arising within the DES secrete a variety of peptides and amines that are found in the circulation and are responsible for the syndromes associated with these tumours. In this review, the most common tumours of the GEP tract are outlined and the circulating products of these tumours identified. Where differential diagnosis is difficult these points are addressed. The peptides most commonly secreted by GEP neuroendocrine tumours are identified and described and their biological activities are discussed. Current methods available for measurement of these peptides are described. Attention is drawn towards molecular specificity where appropriate, as many pancreatic and gut peptides fall within families which show considerable homology, such as the tachykinin family or the glucagon family. Other peptides such as gastrin circulate in multiple molecular forms. This homology and diversity may cause difficulty in the interpretation of peptide measurements in the clinical situation if assays are not specific.

OBJECTIVE

Most studies have considered gastroenteropancreatic neuroendocrine tumors (GEP-NETs) as a homogenous group of samples or distinguish only gastrointestinal from pancreatic endocrine tumors. This article investigates if DNA methylation patterns could distinguish subtypes of GEP-NETs.

METHODS

The DNA methylation level of 807 cancer-related genes was investigated in insulinomas, gastrinomas, non-functioning pancreatic endocrine tumors and small intestine endocrine tumors.

RESULTS

DNA methylation patterns were found to be tumor type specific for each of the pancreatic tumor subtypes and identified two distinct methylation-based groups in small intestine endocrine tumors. Differences of DNA methylation levels were validated by pyrosequencing for 20 candidate genes and correlated with differences at the transcriptional level for four candidate genes.

CONCLUSIONS

The heterogeneity of DNA methylation patterns in the different subtypes of gastroenteropancreatic neuroendocrine tumors suggests different underlying pathways and, therefore, these tumors should be considered as distinct entities in molecular and clinical studies.

Transcription factors (TFs) are critical for B-cell differentiation, affecting gene expression both by repression and transcriptional activation. Still, this information is not used for classification of B-cell lymphomas (BCLs). Traditionally, BCLs are diagnosed based on a phenotypic resemblance to normal B-cells; assessed by immunohistochemistry or flow cytometry, by using a handful of phenotypic markers. In the last decade, diagnostic and prognostic evaluation has been facilitated by global gene expression profiling (GEP), providing a new powerful means for the classification, prediction of survival, and response to treatment of lymphomas. However, most GEP studies have typically been performed on whole tissue samples, containing varying degrees of tumor cell content, which results in uncertainties in data analysis. In this study, global GEP analyses were performed on highly purified, flow-cytometry sorted tumor-cells from eight subgroups of BCLs. This enabled identification of TFs that can be uniquely associated to the tumor cells of chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), hairy cell leukemia (HCL), and mantle cell lymphoma (MCL). The identified transcription factors influence both the global and specific gene expression of the BCLs and have possible implications for diagnosis and treatment.

OBJECTIVE

To determine the frequency of discordant gene expression profile (GEP) classification of posterior uveal melanomas sampled at 2 tumor sites by fine-needle aspiration biopsy (FNAB).

METHODS

Prospective single-institution longitudinal study performed in conjunction with a multicenter validation study of the prognostic value of GEP class of posterior uveal melanoma cells for metastasis and metastatic death.

METHODS

FNAB aspirates of 80 clinically diagnosed primary choroidal and ciliochoroidal melanomas were obtained from 2 tumor sites prior to or at the time of initial ocular tumor treatment and submitted for independent GEP testing and classification. Frequency of discordant GEP classification of these specimens was determined.

RESULTS

Using the support vector machine learning algorithm favored by the developer of the GEP test employed in this study, 9 of the 80 cases (11.3% [95% confidence interval: 9.0%-13.6%]) were clearly discordant. If cases with a failed classification at 1 site or a low confidence class assignment by the support vector machine algorithm at 1 or both sites are also regarded as discordant, then this frequency rises to 13 of the 80 cases (16.3% [95% confidence interval: 13.0%-19.6%]).

CONCLUSIONS

Sampling of a clinically diagnosed posterior uveal melanoma at a single site for prognostic GEP testing is associated with a substantial probability of misclassification. Two-site sampling of such tumors with independent GEP testing of each specimen may be advisable to lessen the probability of underestimating an individual patient's prognostic risk of metastasis and metastatic death.

OBJECTIVE

Although several centers often perform gastric emptying procedures (GEP) together with fundoplication for gastroesophageal reflux (GER) and delayed gastric emptying (DGE), the benefit of GEP is controversial. The present study addresses the question of whether adding a GEP in children with preoperatively diagnosed GER and DGE affects the recurrence rate of GER after Nissen fundoplication (NF).

METHODS

A retrospective chart review was performed on all children under the age of 16 years, operated on for GER from 1980 to 1997, who had a preoperative diagnosis of DGE, and at least 6 months of follow-up. Gastric retention of more than 50% of a radiolabeled meal at 90 minutes was considered DGE. Recurrent reflux was defined as reappearance of GER symptoms, confirmed by postoperative esophagram or 24 hours of pH monitoring.

RESULTS

Of the 183 patients with DGE, 92 were available for long-term follow-up. Of these, 20 had no gastric emptying procedure performed (no-<em>GEP</em> group) and 72 had a <em>GEP</em> performed together with an NF (<em>GEP</em> group). Groups were comparable as to age at operation, mean follow-up time, male to female ratio and prevalence of associated anomalies. A higher prevalence of neurological impairment (NI) was present in the <em>GEP</em> group (48.6% v20.0%). Mean preoperative gastric retention was significantly higher in the <em>GEP</em> group (69.9 +/- 1.3%) than in the no-<em>GEP</em> group (61.4 +/- 2.2%). No complications resulted from the <em>GEP</em>. Recurrent reflux rate was 18.1% in the <em>GEP</em> group (13 of 72) versus 35.0% (7 of 20) in the no-<em>GEP</em> group. Actuarial analysis disclosed a marginally significant difference in the rate of recurrent reflux between the groups (P = .057) and estimation of the relative risk showed a 1.94 increase of recurrent reflux risk in the no-<em>GEP</em> (0.89<RR<4.20).

CONCLUSIONS

Children with DGE, who did not have GEP, had twice the frequency of recurrent reflux as those who had a GER Preoperative screening for DGE, as well as operative correction of DGE at the time of fundoplication, is therefore recommended.

Neuroendocrine tumors (NETs) are rare neoplasms, with an estimated annual incidence of ~ 6.9/100,000. NETs arise throughout the body from cells of the diffuse endocrine system. More than half originate from endocrine cells of the gastrointestinal tract and the pancreas, thus being referred to as gastroenteropancreatic NETs (GEP-NETs). The only treatment that offers a cure is surgery; however, most patients are diagnosed with metastatic disease, and curative surgery is usually not an option. These patients can be offered long-term systemic treatment, for both symptomatic relief and tumor growth suppression. Evidence-based treatment options include somatostatin analogs, everolimus (a mTOR inhibitor), sunitinib (a tyrosine kinase inhibitor), and peptide receptor radionuclide therapy, alone or combined with cytoreductive procedures (surgery or liver-directed procedures). Other treatment options being investigated are immunotherapy and epigenetic assessment that may lead to more personalized interventions. We believe that each patient should be thoroughly evaluated and their case discussed by a multidisciplinary team that is up-to-date with all treatment modalities including ongoing clinical trials, before selecting the proper treatment option.

Gastroenteropancreatic neuroendocrine tumors (GEP/NET) are unusual and rare neoplasms that present many clinical challenges. They characteristically synthesize store and secrete a variety of peptides and neuroamines which can lead to the development of distinct clinical syndrome, however many are clinically silent until late presentation with mass effects. Management strategies include surgery cure and cytoreduction with the use of somatostatin analogues. Somatostatin have a broad range of biological actions that include inhibition of exocrine and endocrine secretions, gut motility, cell proliferation, cell survival and angiogenesis. Five somatostatin receptors (SSTR1-SSTR5) have been cloned and characterized. Somatostatin analogues include octreotide and lanreotide are effective medical tools in the treatment and present selectivity for SSTR2 and SSTR5. During treatment is seen disapperance of flushing, normalization of bowel movements and reduction of serotonin and 5-hydroxyindole acetic acid (5-HIAA) secretion. Telotristat represents a novel approach by specifically inhibiting serotonin synthesis and as such, is a promising potential new treatment for patients with carcinoid syndrome. To pancreatic functionig neuroendocrine tumors belongs insulinoma, gastrinoma, glucagonoma and VIP-oma. Medical management in patients with insulinoma include diazoxide which suppresses insulin release. Also mTOR inhibitors may inhibit insulin secretion. Treatment of gastrinoma include both proton pump inhibitors (PPIs) and histamine H2 - receptor antagonists. In patients with glucagonomas hyperglycaemia can be controlled using insulin and oral blood glucose lowering drugs. In malignant glucagonomas smatostatin analogues are effective in controlling necrolytic migratory erythemia. Severe cases of the VIP-oma syndrome require supplementation of fluid losses. Octreotide reduce tumoral VIP secretion and control secretory diarrhoea.

Endocrine cells occur in the digestive system as micro-organs (islets of Langerhans) or scattered throughout the epithelium of the gastrointestinal tract ("diffuse endocrine epithelial organ" of Feyrter). These gastro-entero-pancreatic (GEP) endocrine cells synthesize--in addition to serotonin--a great variety of polypeptide hormones, which regulate both carbohydrate metabolism and digestive processes. The present review deals mainly with cytology and cytochemistry of GEP endocrine cells. A synopsis is presented of the 19 endocrine cell types identified to date, which includes their update nomenclature and their anatomical distribution pattern. Morphological-functional aspects of cell biology, pathology, and cytogenesis of theses cells and their position within superimposed systems (APUD cells, paraneurons) are discussed.

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are heterogeneous and especially the midgut tumors currently lack effective therapy options. Actionable driver mutations as therapeutic targets are rare. Subtype specific data concerning regulatory mechanisms or epigenetic aberrations are necessary for novel clinical trials. Although the p53 protein itself is rarely mutated in GEP-NENs, epigenetic and regulatory aberrations interfere with the p53 network activity and might function as s target for novel therapeutic approaches. In this review we analyze the current knowledge about the p53 network in GEP-NENs and discuss three possible strategies that include recovering p53 function, enforcing apoptosis by genotoxic stress induction and restoring silenced gene function, based on in vitro, in vivo and clinical data.

To describe the utilization of gene expression profiling (GEP) among California breast cancer patients, identify predictors of use of GEP, and evaluate how utilization of GEP influenced treatment of early-stage breast cancer.

All women diagnosed with hormone-receptor-positive, node-negative breast cancer reported to the California Cancer Registry between January 2008 and December 2010 were linked to Oncotype DX (ODX) assay results.

Overall, 26.7 % of 23,789 eligible patients underwent the assay during the study period. Women age 65 or older were much less likely than women under age 50 to be tested (15.1 vs. 41.4 %, p < 0.001). Black women were slightly less likely and Asian women were slightly more likely than non-Hispanic white women to undergo GEP with the ODX assay (22.2 and 28.9 vs. 26.9 %, respectively, p < 0.001). Patients residing in low SES census tracts had the lowest use of the test (8.9 %), with the proportion increasing with higher SES category. Women with Medicaid health insurance were less likely than other women to be tested (17.7 vs. 27.5 %, p < 0.001). Receipt of adjuvant chemotherapy (ACT) was associated with the ODX recurrence score, although only 63 % of patients whose recurrence scores indicated a high benefit received ACT. Of patients not tested, 15 % received ACT.

Nearly three-fourths of eligible breast cancer patients in California during the 3-year period 2008 through 2010 did not undergo GEP. As a result, it is likely that many women unnecessarily received ACT and suffered associated morbidity. In addition, some high-risk women who would have benefited most from ACT were not identified.

Bone metastases of gastroenteropancreatic neuroendocrine tumors (GEP NET) can be associated with pain and a poor prognosis. Peptide receptor radionuclide therapy (PRRT) has been shown to be effective against this tumor manifestation. This study represents an update of the therapeutic assessment of PRRT with (177)Lu-octreotate in GEP NET patients with bone metastases focusing on potential predictors for impaired outcome and overall survival.We retrospectively analyzed a consecutive subgroup of n=68 patients with bone metastases (BM) of GEP NET treated with (177)Lu-octreotate (4 intended cycles at 3 monthly intervals; mean activity per cycle, 8.1 GBq). Baseline characteristics, including age, performance status, tumor origin, tumor load, plasma chromogranin A (CgA), and neuron-specific enolase (NSE) were analyzed regarding the impact on tumor regression (modified M.D. Anderson criteria) and survival of the patients. Survival analyses were performed using Kaplan-Meier curves, log-rank test at a significance level of p <0.05, and Cox proportional hazards model for uni- and multivariate analyses. Median follow-up was 48 months. The observed response of BMs consisted of complete remission in 2 (2.9%), partial remission in 23 (33.8%), minor response in 8 (11.8%), stable disease in 26 (38.2%), and progressive disease in 8 (13.2%) patients. Median time-to-progression (TTP) of BMs and overall survival (OS) were 35 mo (95% CI: 25-45) and 51 mo (95% CI: 38-64), respectively. Patients with responding BMs survived significantly longer than other patients (median 56 mo vs. 39 mo, p=0.034). NSE >15 ng/ml (p=0.002) and Ki67 index >10% (p=0.008) were associated with shorter overall survival. BM of GEP NET are effectively controlled by PRRT with a long median progression-free survival of approx. 3 years. Non-regression of BM, high proliferation rate and increased plasma NSE at baseline are predictive of shorter survival. However, this study confirms that poor patient condition (Karnofsky-Index ≤70%) and multifocality of BM (>10 lesions) do not affect outcome efficacy, further encouraging the use of PRRT in advanced bone metastatic disease.

BACKGROUND

The 'Study of Intravenous Autologous Marrow in Multiple Sclerosis (SIAMMS)' trial was a safety and feasibility study which examined the effect of intravenous infusion of autologous bone marrow without myeloablative therapy. This trial was well tolerated and improvement was noted in the global evoked potential (GEP)--a neurophysiological secondary outcome measure recording speed of conduction in central nervous system pathways. The efficacy of intravenous delivery of autologous marrow in progressive multiple sclerosis (MS) will be examined in the phase II study the 'Assessment of Bone Marrow-Derived Cellular Therapy in Progressive Multiple Sclerosis (ACTiMuS; NCT01815632)'. In parallel with the 'ACTiMuS' study, the current study 'SIAMMS-II' will explore the feasibility of repeated, non-myeloablative autologous bone marrow-derived cell therapy in progressive MS. Furthermore, information will be obtained regarding the persistence or otherwise of improvements in conduction in central nervous system pathways observed in the original 'SIAMMS' study and whether these can be reproduced or augmented by a second infusion of autologous bone marrow-derived cells.

METHODS

An open, prospective, single-centre phase I extension study. The six patients with progressive MS who participated in the 'SIAMMS' study will be invited to undergo repeat bone marrow harvest and receive an intravenous infusion of autologous, unfractionated bone marrow as a day-case procedure. The primary outcome measure is the number of adverse events, and secondary outcome measures will include change in clinical rating scales of disability, GEP and cranial MRI.

BACKGROUND

The study has UK National Research Ethics Committee approval (13/SW/0255). Study results will be disseminated via peer-reviewed publications and conference presentations.

BACKGROUND

NCT01932593.

Neuroendocrine tumors (NET) are a rare and heterogeneous group of neoplasms of a relatively indolent nature whose incidence and prevalence are increasing. Despite the advances made in the field of NET over the past years, these tumors eventually progress to metastatic disease in most of the patients, with a fatal outcome in the majority. Traditional cytotoxic agents remain of limited efficacy; however, recently, a better understanding of molecular pathways has provided clues to potential molecular targets for new therapeutic strategies. Somatostatin analogs are well known to be useful for the control of symptoms in functioning tumors, and it was recently demonstrated that they can inhibit tumor progression in certain disease settings. Moreover, the recently published randomized trials with the multi-TKI sunitinib and with the mTOR-inhibitor everolimus have demonstrated, for the first time, their ability to positively impact the natural history of pancreatic NET (PNET). In this short review, we will discuss available data on newer molecular targeted agents for the treatment of advanced well-differentiated gastro-entero- pancreatic NET (GEP-NET). A possible algorithm for the use of these treatments in the context of the extreme heterogeneity of GEP-NET presentation will be proposed.

Gastroenteropancreatic neuroendocrine tumours (GEP NETs) represent a heterogenous family of tumours with growing incidence and challenging clinical management. Unlike other solid tumours, they have the ability to secrete different peptides and neuramines that cause distinct clinical syndromes. However, many are clinically silent until advanced disease. This guideline aims to provide practical recommendations for the diagnosis and treatment of GEP NETs. Most recent histological and staging classifications, as well as available therapeutic approaches, such as surgery, locoregional therapy, peptide receptor radionuclide therapy (PRRT) and hormonal or systemic therapy, are discussed in this manuscript, including some recent relevant achievements with novel targeted agents. Clinical presentation (with or without hormonal syndrome), histological tumour features (including proliferation index (Ki-67) and the presence or not of somatostatin receptors), tumour stage, and location of primary tumour and distant metastasis are all key issues that shall be taken into consideration to properly design and integrate the most adequate therapeutic strategy.

Over the last >20 years, we have co-developed the rationale for the first diagnostic and prognostic leukocyte gene expression profiling (GEP) biomarker test in transplantation medicine that gained US-FDA-regulatory clearance and international evidence-based medicine guideline acceptance to rule out moderate/severe acute cellular cardiac allograft rejection without invasive endomyocardial biopsies (EMB). Based on this test, a non-invasive clinical algorithm was implemented since 2005. After clinical implementation, this GEP-based monitoring in direct comparison with an EMB-based strategy was non-inferior with respect to detection of clinical rejection, defined as new onset allograft dysfunction with/without histology of ACR, re-transplantation or death, and at the same time improved patient satisfaction. Subsequently, we demonstrated the test's capacity when used as serial monitoring tool to predict these clinical rejection events. In this Personal Viewpoint article, I will discuss the various decision-making branching points that were made in the AlloMap biomarker test development to inform future genomic biomarker test development projects.

The role of PET in the assessment of endocrine tumours has been, until recently, restricted to the use of (18)F-fluoro-deoxy-D-glucose ((18)F-FDG). Being a marker of metabolically active lesions that show high grading and low differentiation, FDG is not ideal for this purpose since the majority of endocrine tumours are slow growing and highly differentiated. It is however useful when dedifferentiation takes place and provides excellent prognostic information. A number of hormone precursors and amino acids are labelled with (11)C and used successfully in the management of parathyroid, adrenal and pituitary tumours. However, the short half-life of (11)C radiopharmaceuticals restricts their use to centres with access to an on-site cyclotron, while the high cost of production may limit their use to research purposes. A promising new positron-emission tomography (PET) tracer is Gallium-68 obtained by elution from a long shelf-life generator that makes it economic and cyclotron-independent. Its short half-life and flexible labelling ability to a wide range of peptides and antibodies makes it ideal for PET imaging. In addition to imaging GEP-NETs and phaeochromocytoma, it has the potential to be used in a wider range of endocrine tumours.

The antiproliferative effect of somatostatin-14 and its analogue, octreotide, on in vitro pancreatic and breast tumor cells has led to the suggestion that octreotide may have further oncological indications in addition to its use in the treatment of gastroentero-pancreatic (GEP) tumors. To extend these in vitro observations, we evaluated the effect of octreotide in rodent models of pancreatic and breast tumors. Octreotide at a dose of 5 micrograms or 50 micrograms twice a day in nude mice bearing solid MiaPaCa pancreatic tumors (subline 21) or ZR-75-1 breast tumors induced a significant inhibition of tumor growth from week 2 until the end of treatment at week 5. After 5 weeks, the mean volume of ZR-75-1 tumors in animals treated with the 50-micrograms regimen was 48% of that in controls. Autoradiographic studies showed that a high percentage (71%) of ZR-75-1 tumors were somatostatin receptor-positive. In addition, the growth of ZR-75-1 cells in vitro was significantly inhibited by octreotide. The drug was also tested in a second breast cancer model, 7,12-dimethylbenzanthracene (DMBA)-induced mammary tumors in rats, and continuous administration of 10 micrograms/kg/h over 6 weeks led to an approximate 50% reduction in the number of tumors arising in the rat mammary gland. These data suggest that pancreatic and breast cancer may be among the malignant diseases clinically susceptible to octreotide.

OBJECTIVE

To quantify healthcare resource use (HRU) and costs in relation to carcinoid syndrome (CS) and carcinoid heart disease (CHD) in a real-world setting, and to provide perspective on treatment patterns.

METHODS

Patient data and HRU were collected retrospectively from three Swedish healthcare registers. Adult patients diagnosed with metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NETs) grade 1 or 2 and CS who purchased somatostatin analogs (SSAs), and experienced controlled (defined by SSAs use) and uncontrolled (defined by SSAs dose escalation) CS for ≥8 months during the study period were included. Patients diagnosed with CHD from the date of the GEP-NET diagnosis were included in the CHD study group.

RESULTS

Overall, total HRU cost increased with uncontrolled CS and CHD. Total resource cost was 15,500€/patient during controlled CS (8 months), rising to 21,700€/patient during uncontrolled CS (8 months), representing an increase of ∼40% (6200€/patient). Costs/patient were driven mainly by SSA use, tumor-related medical interventions and examinations. The total mean cost/year of disease was 1100€/patient without CHD, compared to 4600€/patient with CHD, a difference of 3500€/patient. Excluding SSA cost burden, the main drivers of increased cost in CHD patients were surgical interventions and echocardiography.

CONCLUSIONS

This study provides a comprehensive overview of the treatment patterns and burden of uncontrolled CS symptoms and CHD using Swedish national register data. Increases in medical interventions and examinations HRU and increased SSA use suggest that SSA dose escalation alone may not effectively control the symptoms associated with uncontrolled CS, highlighting an unmet treatment need in this patient group.