Management of patients with rare adult solid cancers: objectives and evaluation of European reference networks (ERN) EURACAN

About 500,000 patients with rare adult solid cancers (RASC) are diagnosed yearly in Europe. Delays and unequal quality of management impact negatively their survival. Since 2017, European reference networks (ERN) aim to improve the quality of care of patients with rare disease. The steering committee of EURACAN, including physicians, researchers and patients review here the previous actions, present objectives of the ERN EURACAN dedicated to RASC. EURACAN promoted management in reference centres, and equal implementation of excellence and innovation in Europe and developed 22 clinical practice guidelines (CPGs). Additionally, fourteen information brochures translated in 24 EU languages were developed in collaboration with patient advocacy groups (ePAGs) and seventeen training session were organized. Nevertheless, connections to national networks in the 26 participating countries (106 centres), simplification of cross-border healthcare, international multidisciplinary tumour boards, registries and monitoring of the quality of care are still required. In this Health Policy, evaluation criteria of the performances of the network and of health care providers are proposed.

Peritoneal metastases in patients with neuroendocrine neoplasms: a challenging site of metastases with clinical and prognostic implications

PURPOSE

Peritoneal metastases (PM) of neuroendocrine neoplasm (NEN) origin are identified with increasing frequency and exert a significant effect on quality of life and clinical status of the patients. The aim of this study was to identify the characteristics and the prognostic significance of PM in patients with NENs.

METHODS

A retrospective analysis of the data of patients from two tertiary referral centers was performed. We defined a control group of age- and gender-matched NEN patients with comparable stage IV disease but no PM.

RESULTS

We analysed 70 patients (41 females) with PM. Small intestine was the most common primary NEN site (87.1%). PM prevalence was 10.3%. Forty-four patients presented with synchronous PM, whereas 26 developed metachronous PM. The majority of patients had other concomitant metastases (50 hepatic, 6 lung and 12 bone metastases). Twelve patients developed intestinal obstruction. After PM diagnosis, 76% of patients received treatment with somatostatin analogues while six patients (8.6%) were treated with peptide receptor radionuclide therapy (PRRT). The median progression-free survival (PFS) in the PRRT-treated group was 15 months (95% CI 2-28). Median overall survival (OS) in the PM group was 142 months [95% CI 71-213] while it was not reached in the control group.

CONCLUSION

Peritoneal metastases show low prevalence among NEN patients and are most likely to develop in patients with small intestinal NENs and advanced metastatic disease. The presence of PM does seem to be associated with a negative prognostic impact on OS of NEN patients and their identification and prompt treatment is of major importance.

PREF-NET: a patient preference and experience study of lanreotide autogel administered in the home versus hospital setting among patients with gastroenteropancreatic neuroendocrine tumours in the UK

PURPOSE

PREF-NET reported patients' experience of Somatuline® (lanreotide) Autogel® (LAN) administration at home and in hospital among patients with gastroenteropancreatic neuroendocrine tumours (GEP-NETs).

METHODS

PREF-NET was a multicentre, cross-sectional study of UK adults (aged ≥ 18 years) with GEP-NETs receiving a stable dose of LAN, which comprised of (1) a quantitative online survey, and (2) qualitative semi-structured interviews conducted with a subgroup of survey respondents. The primary objective was the description of overall patient preference for home versus hospital administration of LAN. Secondary objectives included describing patient-reported opinions on the experience and associated preference for each administration setting, and the impact on healthcare utilisation, societal cost, activities of daily living and health-related quality of life (HRQoL).

RESULTS

In the primary analysis (80 patients; mean age 63.9 years), 98.7% (95% confidence interval [CI]: 96.1-100.0) of patients preferred to receive LAN at home, compared with 1.3% (95% CI: 0.0-3.9) who preferred the hospital setting. Among participants, over half (60.3%) received their injection from a non-healthcare professional. Most patients (79.5% [95% CI: 70.5-88.4]) reported a positive effect on HRQoL after the switch from hospital to home administration. Qualitative interviews (20 patients; mean age 63.6 years) highlighted that patients preferred home administration because it improved overall convenience; saved time and costs; made them feel more comfortable and relaxed, and less stressed; and increased confidence in their ability to self-manage their treatment.

CONCLUSION

Almost all patients preferred to receive LAN treatment at home rather than in hospital with increased convenience and psychological benefits reported as key reasons for this preference.

Endoscopic Management of Gastro-Entero-Pancreatic Neuroendocrine Tumours: An Overview of Proposed Resection and Ablation Techniques

A literature search of MEDLINE/PUBMED was conducted with the aim to highlight current endoscopic management of localised gastro-entero-pancreatic NETs. Relevant articles were identified through a manual search, and reference lists were reviewed for additional articles. The results of the research have been displayed in a narrative fashion to illustrate the actual state-of-the-art of endoscopic techniques in the treatment of NETs. Localised NETs of the stomach, duodenum and rectum can benefit from advanced endoscopic resection techniques (e.g., modified endoscopic mucosal resection, endoscopic full thickness resection, endoscopic submucosal dissection) according to centre expertise. Radiofrequency thermal ablation can be proposed as an alternative to surgery in selected patients with localised pancreatic NETs.

Use and perceived utility of [18 F]FDG PET/CT in neuroendocrine neoplasms: A consensus report from the European Neuroendocrine Tumor Society (ENETS) Advisory Board Meeting 2022

Somatostatin receptor (SST) PET/CT is the gold standard for well-differentiated neuroendocrine tumours (NET) imaging. Higher grades of neuroendocrine neoplasms (NEN) show preferential [18F]FDG (FDG) uptake, and even low-grade NET may de-differentiate over time. FDG PET/CT's prognostic role is widely accepted; however, its impact on clinical decision-making remains controversial and its use varies widely. A questionnaire-based survey on FDG PET/CT use and perceived decision-making utility in NEN was submitted to the ENETS Advisory Board Meeting attendees (November 2022, response rate = 70%). In 3/15 statements, agreement was higher than 75%: (i) FDG was considered useful in NET, irrespective of grade, in case of mis-matched lesions (detectable on diagnostic CT but negative/faintly positive on SST PET/CT), especially if PRRT is contemplated (80%); (ii) in NET G3 if curative surgery is considered (82%); and (iii) in NEC prior to surgery with curative intent (98%). FDG use in NET G3, even in the presence of matched lesions, as a baseline for response assessment was favoured by 74%. Four statements obtained more than 60% consensus: (i) FDG use in NET G3 if locoregional therapy is considered (65%); (ii) in neuroendocrine carcinoma before initiating active therapy as a baseline for response assessment (61%); (iii) biopsy to re-assess tumour grade prior to a change in therapeutic management (68%) upon detection of FDG-positivity on the background of a prior G1-2 NET; (iv) 67% were in favour to reconsider PRRT to treat residual SST-positive lesions after achieving complete remission on FDG of the SST-negative disease component. Multidisciplinary opinion broadly supports the use of FDG PET/CT for characterisation of disease biology and to guide treatment selection across a range of indications, despite the lack of full consensus in many situations. This may reflect existing clinical access due to lack of reimbursement or experience with this investigation, which should be addressed by further research.

Plasma or serum 5-hydroxyindoleacetic acid can be used interchangeably in patients with neuroendocrine tumours

5-hydroxyindole acetic acid, a metabolite of serotonin, is used in the diagnosis and monitoring of patients with neuroendocrine tumours, in particular patients with small intestinal neuroendocrine tumours associated with the carcinoid syndrome. Analysis of 5-hydroxyindole acetic acid was commonly performed in urine, but blood-based assays are now becoming available. The objective of this study was to assess how 5-hydroxyindole acetic acid compares in plasma and serum as a biochemical marker of neuroendocrine tumours. Twenty-four-hour urine, plasma and serum samples were obtained from 80 patients with neuroendocrine tumours and 30 healthy volunteers. We developed a liquid chromatography tandem mass spectrometry assay for plasma and serum 5-hydroxyindole acetic acid. Comparison was made between them, and their cut-off was determined using a receiver-operating characteristic curve. A close correlation was shown between plasma and serum 5-hydroxyindole acetic acid. At a cut-off of 135 nmol/l, a sensitivity of 91.2% with a specificity of 61.9% was obtained for both compared to the urinary assay. A statistically significant agreement was shown when plasma and serum 5-hydroxyindole acetic acid were compared with the currently used urine assay in patients with neuroendocrine tumours; κ = 0.675 (95% CI 0.49 to 0.86), p < 0.001 and healthy volunteers; 0.967 (95% CI 0.828 to 0.999), p = <0.001. In conclusion, 5-hydroxyindole acetic acid in plasma and serum were comparable, hence either sample type can be used interchangeably.

Management Strategies and Outcomes for Small Intestinal Neuroendocrine Tumours with Involvement of the Superior Mesenteric Vessels: A Systematic Review

Small intestinal neuroendocrine tumours (SI-NETs) are the most common small intestinal tumours. A particularly challenging subset of these tumours is those that involve the superior mesenteric artery or vein for which the role and feasibility of surgery are often questioned. This systematic review aimed to identify and evaluate the management strategies used for these complex SI-NETs. The identified studies showed positive outcomes with surgery and multimodality therapy.

Safety and Efficacy of 177Lu-DOTATATE in Neuroendocrine Tumor Patients With Extensive Bone Disease

AIM

The aim of this study was to assess the efficacy and safety of 177Lu-DOTATATE in patients with neuroendocrine tumors (NETs) and extensive bone metastases, that is, more than 50% of the skeleton involved.

METHOD

A single-center retrospective analysis was performed in 30 patients (13 women and 17 men, mean age, 60 years; range, 35-77 years) undergoing 177Lu-DOTATATE therapy. Patients had progressive metastatic NETs with extensive skeletal metastases (>50% skeletal involvement seen on baseline 68Ga-DOTATATE PET/CT). The average administered activity was 7.308 (SD, 0.02) GBq per cycle with average treatment interval of 15 weeks. Survival analyses (progression-free survival [PFS], overall survival), radiological response assessment, toxicity assessment, and health-related quality of life (QoL) was performed.

RESULTS

Overall, 26 patients completed 4 cycles, and 4 patients had less than 4 cycles of 177Lu-DOTATATE. One patient (3%) did not complete treatment because of hematological toxicity. The estimated median PFS and median overall survival were calculated at 27 and 35 months, respectively. End-of-treatment radiological assessment showed partial response in 5 patients (17%), stable disease in 20 patients (66%), and radiological progressive disease in 3 patients (10%). Clinical progression was seen in a further 2 patients (7%).The incidence of grade 3/4 bone marrow toxicity was 10%. No patient had grade 3/4 peptide receptor radionuclide therapy-related nephrotoxicity. There was overall improvement in global QoL score (European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Gastrointestinal NET-21) (P = 0.019).

CONCLUSION

177Lu-DOTATATE seems to have satisfactory therapeutic outcome in patients with advanced metastatic NET with extensive bone disease, with reasonable PFS and significant improvement in the global health-related QoL. The bone marrow toxicity was within the accepted range. Increasing the interval between cycles does not seem to reduce efficacy and may reduce toxicity, ensuring the bone marrow has sufficient time to recover between cycles.

Single centre retrospective review of outcome of 177 Lu-DOTATATE peptide receptor radionuclide therapy in the treatment of progressive metastatic neuroendocrine tumours: Survival, toxicity, and prognostic factors

The aim of this study was to evaluate the efficacy and safety of ¹⁷⁷ Lu-DOTATATE therapy in advanced metastatic disease. A retrospective analysis of 395 patients (180 female, 215 males, mean age 62) with progressive metastatic neuroendocrine tumours (NETs) who were treated with ¹⁷⁷ Lu-DOTATATE was performed. Overall, 115 patients had less than four cycles and 280 completed four cycles of treatment. Progression-free survival (PFS) and overall survival (OS) was performed using Kaplan-Meier analysis. Analysis of survival predictors was performed using Cox regression model. Toxicity was defined using the Common Terminology Criteria for Adverse Events version 5 (CTCAE 5.0). The percentage of patients with liver and skeletal metastases were 91 and 57%, respectively. Median PFS and OS were calculated at 33 months (95% CI: 29-37 months) and 46 months (95% CI: 48-56 months), respectively. End of treatment response assessment was performed using cross sectional imaging demonstrated partial response in 22%, stable disease in 64% and progressive disease in 14% of patients. Overall, grade 3 and 4 bone marrow toxicity was seen in 8%. One patient (0.3%) developed irreversible grade 4 nephrotoxicity. Myelodysplastic disease was recorded in one patient (0.3%). Univariate analysis of PFS predictors showed that body mass index (BMI), baseline chromogranin A (CgA) >400 ng/l, baseline alkaline phosphatase (ALP) >130 mg/dl, liver tumour volume and overall tumour burden were significant. On multivariate analysis only Ki67, high CgA and low BMI retained significance. ¹⁷⁷ Lu-DOTATATE is an effective treatment in advanced NETs with generally high-volume metastases. It is well-tolerated. Ki-67, CgA and BMI appear to be predictors for PFS.

The impact of COVID-19 on the management of neuroendocrine tumors (NETS): An international NET CONNECT survey of NET patients and healthcare professionals treating net patients

The COVID-19 outbreak has added complexity in the management of patients with neuroendocrine tumors (NETs). Little information is currently available regarding the real impact of the pandemic in current practice. The present study aimed to capture patients' and healthcare professionals' experiences on how the NET management has changed during the pandemic and how it should be modified in a foreseeable post-pandemic environment. Physicians and nurses working in ENETS Centers of Excellence or other hospitals with high volume of NET patients (n = 48), as well as NET patients residing worldwide (n = 353), were asked to respond to two online anonymous surveys addressing different aspects of NET care. Deferred diagnoses, delayed surveillance procedures and postponed elective surgeries were among the main negative consequences of the COVID-19 outbreak according to 40%, 54% and 46% of healthcare professionals (HPs) respectively. Somatostatin analogs were increasingly used as bridging strategy for delaying surgery based on the views of 31% of HPs and were self-injected or delivered by home care services more frequently than before the initiation of the pandemic (53% of patients during the pandemic vs. 44% before the pandemic). Multidisciplinary tumor boards kept their usual schedule according to 58% of HPs, but were held virtually in the 77% of cases. The contact with healthcare professionals was maintained by remote methods more often than in the past (69% of patients), but only 34% of patients (59% among subjects < 41 years) would prefer telemedicine to face-to-face consultations in the future. New health policy measures should guarantee the highest standard of treatment to NET patients, regardless of the trajectory followed by the COVID-19 pandemic in the next months. Pros and cons of telemedicine should be carefully weighted before systematic implementation.

Insulinoma: a quarter century of dietary control

Summary

Insulinomas are rare pancreatic neuroendocrine neoplasms (NENs) that are typically sporadic and solitary, with the majority being <2 cm in diameter at diagnosis. The median duration of symptoms before diagnosis is variable; however, this is usually in the region of 12-18 months. We report on an insulinoma diagnosed some 25 years following initial symptoms, having by that stage attained a diameter of 4 cm. We present a 50-year-old man who was reported with hypoglycaemic symptoms on his wedding 25 years prior to eventual confirmation of an insulinoma. He had since learned to live with the symptoms by eating frequently to manage his hypoglycaemia. However, over recent months, he reported a substantial deterioration in his symptoms, and indeed, had collapsed on two occasions. He had a fasting glucose of 2.9 mmol/L with grossly inappropriate elevated insulin and C-peptide levels. MRI demonstrated a 4.1 cm lesion at the body of pancreas and an indeterminate 9-mm liver lesion with a negative 68Gallium-DOTATATE PET scan. Accordingly, he was initiated on diazoxide and referred to the surgical team for distal pancreatectomy: histology confirmed a 4.4-cm well-differentiated pancreatic NEN of intermediate grade (NEN G2, Grade 2, 2017 World Health Organization (WHO) pancreatic-NEN classification), with positive immunohistochemistry for insulin. His hypoglycaemia episodes have ceased, and he remains under active surveillance. Our case demonstrates the possibility of dietary control of insulinoma-induced hypoglycaemia, and the likelihood that such a prolonged delay in diagnosis has led to the uncommonly large size of the apparently benign tumour which is usually 'small and indolent'.

Learning points

Most patients with insulinomas have lesions that are 1-2 cm in size, with 96% being less than 3 cm. The mean tumour size of insulinomas found in 3 of the largest reported series was 1.5 cm, with a range of 0.1-7.0 cm. It is not uncommon for patients to have symptoms for several months to years before diagnosis; however, no reported cases had the symptoms such long for 25 years, and the large size of the tumour in this case may reflect the very long history.

Systematic Evaluation of the Immune Environment of Small Intestinal Neuroendocrine Tumors

PURPOSE

The immune tumor microenvironment and the potential therapeutic opportunities for immunotherapy in small intestinal neuroendocrine tumors (siNET) have not been fully defined.

EXPERIMENTAL DESIGN

Herein, we studied 40 patients with primary and synchronous metastatic siNETs, and matched blood and normal tissue obtained during surgery. We interrogated the immune checkpoint landscape using multi-parametric flow cytometry. In addition, matched FFPE tissue was obtained for multi-parametric IHC to determine the relative abundance and distribution of T-cell infiltrate. Tumor mutational burden (TMB) was also assessed and correlated with immune infiltration.

RESULTS

Effector tumor-infiltrating lymphocytes (TIL) had a higher expression of PD-1 in the tumor microenvironment compared with the periphery. In addition, CD8+ TILs had a significantly higher co-expression of PD-1/ICOS and PD-1/CTLA-4 (cytotoxic T lymphocyte antigen-4) and higher levels of PD-1 expression compared with normal tissue. IHC revealed that the majority of cases have ≤10% intra-tumoral T cells but a higher number of peri-tumoral T cells, demonstrating an "exclusion" phenotype. Finally, we confirmed that siNETs have a low TMB compared with other tumor types in the TCGA database but did not find a correlation between TMB and CD8/Treg ratio.

CONCLUSIONS

Taken together, these results suggest that a combination therapy approach will be required to enhance the immune response, using PD-1 as a checkpoint immunomodulator backbone in combination with other checkpoint targeting molecules (CTLA-4 or ICOS), or with drugs targeting other pathways to recruit "excluded" T cells into the tumor microenvironment to treat patients with siNETs.

Circulating tumour cells and tumour biomarkers in functional midgut neuroendocrine tumours

CALM-NET was a phase IV exploratory study in the UK that aimed to evaluate if the presence of circulating tumour cells (CTCs) at baseline predicted symptomatic response in patients with midgut neuroendocrine tumours (NETs) treated with lanreotide autogel (LAN). Adults with functional, well/moderately differentiated (Ki-67 <20%) midgut NETs received LAN 120 mg/28 days for 1 year. CTCs were present in blood if enumeration was >0. Primary endpoint was the clinical value of baseline CTCs to predict symptomatic response (decrease in diarrhoea or flushing of ≥50% frequency, or ≥1 severity level). Other endpoints included progression-free survival (PFS) and correlations between plasma and urinary biomarkers (including 5-hydroxyindoleacetic acid [5-HIAA]). Fifty patients were enrolled; 40 completed the study. Baseline CTCs were present in 22 (45.8%) patients (missing baseline CTC status n = 2). Overall, 87.5% (95% confidence interval [CI]: 73.9; 94.5) of patients had a symptomatic response; a 5.9-fold higher odds of symptomatic response in patients without CTC versus patients with CTC at baseline was observed, although this was not statistically significant (odds ratio: 0.17 [95% CI: 0.02; 1.65], p = .126). One-year PFS rate was 66.4% (95% CI: 48.8; 79.2). Biomarker concentrations did not correlate to baseline CTC status. However, there was a strong correlation between plasma and urinary 5-HIAA (Spearman correlation coefficients ≥0.87 [p < .001], all time points). In conclusion, patients without CTC at baseline may be more likely to achieve a symptomatic response following LAN treatment than patients with CTC. Plasma 5-HIAA correlated with urinary 5-HIAA during LAN treatment. ClinicalTrials.gov identifier: NCT02075606.

Treatment of neuroendocrine tumours with 177 Lu-peptide receptor radionuclide therapy: Challenging clinical scenarios and their management

Peptide receptor radionuclide therapy (PRRT) for the treatment of patients with neuroendocrine tumours is usually well tolerated, with selection based on existing guidelines. However, there are various scenarios where the risk-benefit analysis of PRRT needs to be evaluated to limit any complications associated with PRRT. This review looks at 11 key scenarios where the risk-benefit of PRRT needs to be closely evaluated.

ENETS standardized (synoptic) reporting for endoscopy in neuroendocrine tumors

Despite efforts from various endoscopy societies, reporting in the field of endoscopy remains extremely heterogeneous. Harmonisation of clinical practice in endoscopy has been highlighted by application of many clinical practice guidelines and standards pertaining to the endoscopic procedures and reporting are underlined. The aim of the proposed "standardised reporting" is to (1) facilitate recognition of gastrointestinal neuroendocrine neoplasms (NEN) on initial endoscopy, (2) to enable interdisciplinary decision making for treatment by a multidisciplinary team, (3) to provide a basis for a standardised endoscopic follow-up which allows detection of recurrence or progression reliably, (4) to make endoscopic reports on NEN comparable between different units, and (5) to allow research collaboration between NEN centres in terms of consistency of their endoscopic data. The ultimate goal is to improve disease management, patient outcome and reduce the diagnostic burden on the side of the patient by ensuring the highest possible diagnostic accuracy and validity of endoscopic exams and possibly interventions.

Safety of peptide receptor radionuclide therapy with 177Lutetium DOTATATE in neuroendocrine tumour patients with chronic kidney disease

Purpose: To assess efficacy and safety of ¹⁷⁷Lu-DOTATATE in patients with neuroendocrine tumours (NETs) with reduced renal function i.e., eGFR below 60 ml/min/1.73 m2. Methods: A single-centre retrospective analysis was performed in 33 patients with eGFR less than 60 ml/min/1.73 m2. Of these 33 patients, 26 patients had chronic kidney disease (CKD) stage 3a (eGFR between 45-60 ml/min/1.73 m2) and 7 patients had CKD stage 3b (eGFR between 30-45 ml/min/1.73 m2). Renal toxicity and temporal changes in eGFR were recorded. Association of potential risk factors and any kidney function deterioration (>10% reduction of eGFR) was evaluated. Survival, radiological response assessment and quality of life data was collected. Results: The incidence of permanent grade 3/4 nephrotoxicity was 3% (single patient with grade 4 nephrotoxicity). The mean annual reduction of eGFR estimated at 2.5%. Permanent decline of >10% eGFR of any grade was recorded in 45% of patients (n = 15). Nine patients moved into higher CKD categories (eight patients who moved from CKD 3a to CKD 3b and one patient who moved from CKD3b to CKD 5). No significant relationship was found between renal risk factors and permanent reduction of renal function. Grade 3/4 bone marrow toxicity was observed in 9% of patients. The estimated median progression-free survival (PFS) was 42 months and median overall survival (OS) was 47 months. At the end of the treatment, the radiological assessment showed partial response in 33%, stable disease in 55%, and progressive disease in 12%. There was an improvement in global quality of life and endocrine score (EORTC QLQ-GI-NET21) (p value: 0.046 and 0.041 respectively). Conclusion: ¹⁷⁷Lu-DOTATATE appears to be generally well-tolerated in patients with pre-existing CKD stage 3 with a low incidence of permanent major nephrotoxicity. ¹⁷⁷Lu-DOTATATE appears to have a good therapeutic effect; with most patients reporting improvement in quality of life.

Prognostic stratification for patients with neuroendocrine tumours receiving 177Lu-Dotatate

177Lu-Dotatate is increasingly used in patients with advanced neuroendocrine tumour (NET). However, few prognostic markers are available to stratify progression-free survival (PFS) of patients who received 177Lu-Dotatate. Clinicopathological data including baseline circulating biomarkers of patients with advanced NET who received 177Lu-Dotatate were routinely collected and were retrospectively analysed. Continuous variables were normalized by dividing them by their upper normal limits. The whole data set was randomly divided into a training set and a validation set. Univariate and multivariate logistic regression analyses were used to identify independent markers and to develop a scoring model to predict treatment failure at 1 year. In total, 195 patients were included. Elevated baseline chromogranin A (CgA), normal creatinine and previous chemotherapy were three risk factors independently associated with 1-year treatment failure. By combining these risk factors, a scoring model was developed which could accurately predict 1-year treatment failure both in the training set (area under curve, AUC, 0.813; 95% CI, 0.731-0.895; P< 0.001) and in the validation set (AUC, 0.816; 95% CI, 0.644-0.968; P< 0.001). After selecting a score of 29.7 as the cut-off value of the scoring model, patients could be stratified into two groups namely low-risk and high-risk with significantly different 1-year treatment failure rate, PFS and overall survival (OS; P< 0.001) both in the training set and validation set. In conclusion, baseline CgA, creatinine level and previous chemotherapy were independently associated with 1-year treatment failure of patients with advanced NET who received 177Lu-Dotatate and the scoring model and prognostic stratification based on these markers could accurately predict 1-year treatment failure, PFS and OS.

Long-Term Treatment with Telotristat Ethyl in Patients with Carcinoid Syndrome Symptoms: Results from the TELEPATH Study

INTRODUCTION

Telotristat ethyl is indicated for use in combination with somatostatin analogs (SSAs) to treat carcinoid syndrome (CS) diarrhea uncontrolled by SSAs alone in adults, but long-term safety and efficacy data beyond 48 weeks are needed.

OBJECTIVES

The aims of the study were to evaluate the long-term safety and tolerability of telotristat ethyl and its effect on quality of life (QOL) in patients with CS.

METHODS

In this phase 3, nonrandomized, multicenter, open-label, long-term extension study (TELEPATH), patients who participated in phase 2 or 3 trials of telotristat ethyl continued treatment at their present dose level (250 or 500 mg thrice daily) for 84 weeks. Safety and tolerability, the primary endpoint, were assessed by monitoring adverse events (AEs), serious AEs, AEs of special interest (AESIs; including liver-related AEs, depression, and gastrointestinal AEs), and deaths. The secondary objective was to evaluate changes in patients' QOL using validated cancer questionnaires and a subjective global assessment of CS symptoms.

RESULTS

In 124 patients exposed to telotristat ethyl for a mean of 102.6 ± 53.2 weeks, the type and frequency of AEs were consistent with those reported in previous trials. The occurrence of AESIs was not related to dosage or duration of therapy. Most AEs were mild to moderate in severity, and no deaths were related to telotristat ethyl. QOL scores remained stable, and the majority of patients reported adequate symptom relief throughout the study.

CONCLUSIONS

Safety results of TELEPATH support the long-term use of telotristat ethyl in patients with CS diarrhea. Telotristat ethyl was well-tolerated and associated with sustained improvement in QOL scores (NCT02026063).

Use of [177Lu]Lu-DOTA-TATE in the treatment of gastroenteropancreatic neuroendocrine tumours: Results of a UK cost-effectiveness modelling study

Aim

To evaluate the cost-effectiveness of [¹⁷⁷Lu]Lu-DOTA-TATE versus relevant comparators for the treatment of neuroendocrine tumours located in the gastrointestinal tract (GI-NETs) and the pancreas (P-NETs).

Materials and methods

A three-state partitioned survival model was developed to perform a cost-utility analysis of [¹⁷⁷Lu]Lu-DOTA-TATE versus standard of care (high dose Octreotide LAR), everolimus and sunitinib. Effectiveness data for SoC, everolimus and sunitinib were obtained from published Kaplan–Meier survival curves. Given a lack of head-to-head effectiveness data, matching adjusted indirect comparisons (MAICs) were performed to population-adjust [¹⁷⁷Lu]Lu-DOTA-TATE survival data based on prognostic factors and derive estimates of relative effectiveness. Health state utilities were estimated from real-world evidence. Drug acquisition costs were taken from nationally published sources (BNF, NICE), and administration costs were based on treatment protocols in [¹⁷⁷Lu]Lu-DOTA-TATE studies, combined with nationally published unit costs (PSSRU, DoH reference costs). Incidence of adverse events were estimated using published sources. A discount rate of 3.5% was applied to both utilities and costs, and deterministic and probabilistic sensitivity analyses were performed. Costs were included from an NHS perspective and presented in 2017/18 GBP (and PPP Euros for base case).

Results

In GI-NETs, the incremental cost-effectiveness ratio (ICER) of [¹⁷⁷Lu]Lu-DOTA-TATE compared to SoC and everolimus was £26,528 (€27,672) and £24,145 (€25,186) per QALY, respectively. In P-NETs, the ICER of [¹⁷⁷Lu]Lu-DOTA-TATE compared to SoC was £22,146 (€23,101) or £28,038 (€29,251) dependent on matched population, and £21,827 (€22,766) and £15,768 (€16,445) compared to everolimus and sunitinib, respectively.

Conclusions

At a willingness to pay threshold of £30,000, [¹⁷⁷Lu]Lu-DOTA-TATE is likely to be a cost-effective treatment option for GI-NET and P-NET patients versus relevant treatment comparators (NHS perspective).

•

A three-state partitioned survival model of GEP-NET patients was developed.

•

Base case ICERs for [¹⁷⁷Lu]Lu-DOTA-TATE were under £30,000 per QALY for all comparators.

•

[¹⁷⁷Lu]Lu-DOTA-TATE is cost-effective for the treatment of GEP-NETs from a NICE perspective.

Middle ear neuroendocrine tumours: Insight into their pathogenesis, diagnosis and management

Recent advances in the diagnosis of neuroendocrine tumours (NETs) have led to the identification of NETs in unusual locations. NETs originating in the middle ear have been reported in a number of case reports with differing terminologies, where they were variously referred to as middle ear adenomas or middle ear carcinoids. In this report, we describe two cases of middle ear NETs with locally advanced disease and with distant metastases, respectively. The embryological origin, pathogenesis and histopathological characteristics, including immunohistochemical markers, are discussed aiming to clarify the terminology of these tumours. Functional imaging modalities (eg, 68 Ga-DOTATATE positron emission tomography/computed tomography/magnetic resonance imaging) play a pivotal role in the diagnosis, staging and determining the optimal systemic therapy in managing NETs of the middle ear. In addition, surgical, local and systemic therapeutic modalities are discussed, including the management option of long-acting somatostatin analogue therapy and targeted radionuclide therapy for somatostatin receptor-positive well-differentiated middle ear NETs.

Whole-genome sequencing of single circulating tumor cells from neuroendocrine neoplasms

Single-cell profiling of circulating tumor cells (CTCs) as part of a minimally invasive liquid biopsy presents an opportunity to characterize and monitor tumor heterogeneity and evolution in individual patients. In this study, we aimed to compare single-cell copy number variation (CNV) data with tissue and define the degree of intra- and inter-patient genomic heterogeneity. We performed next-generation sequencing (NGS) whole-genome CNV analysis of 125 single CTCs derived from seven patients with neuroendocrine neoplasms (NEN) alongside matched white blood cells (WBC), formalin-fixed paraffin-embedded (FFPE), and fresh frozen (FF) samples. CTC CNV profiling demonstrated recurrent chromosomal alterations in previously reported NEN copy number hotspots, including the prognostically relevant loss of chromosome 18. Unsupervised hierarchical clustering revealed CTCs with distinct clonal lineages as well as significant intra- and inter-patient genomic heterogeneity, including subclonal alterations not detectable by bulk analysis and previously unreported in NEN. Notably, we also demonstrated the presence of genomically distinct CTCs according to the enrichment strategy utilized (EpCAM-dependent vs size-based). This work has significant implications for the identification of therapeutic targets, tracking of evolutionary change, and the implementation of CTC-biomarkers in cancer.

Safety, tolerability and clinical implementation of 'ready-to-use' 68gallium-DOTA0-Tyr3-octreotide (68Ga-DOTATOC) (SomaKIT TOC) for injection in patients diagnosed with gastroenteropancreatic neuroendocrine tumours (GEP-NETs)

BACKGROUND

⁶⁸Ga-DOTA0-Tyr3-octreotide (⁶⁸Ga-DOTATOC) positron emission tomography-CT (PET-CT) has superior diagnostic performance compared to the licensed tracer OctreoScan single photon emission CT-CT in patients with gastroenteropancreatic neuroendocrine tumours (GEP-NETs). A new preparation of ⁶⁸Ga-DOTATOC using a new 'ready-to-use' ⁶⁸Ga-DOTATOC formulation for injection has been developed (⁶⁸Ga-DOTATOC (SomaKIT TOC)).

OBJECTIVES

This study aimed to assess the safety and tolerability of ⁶⁸Ga-DOTATOC (SomaKIT TOC) and evaluate the feasibility and robustness of implementing it in a NET clinical imaging service.

METHODS

A first-in-human phase I/II multicentre, open-label study of a single dose of ⁶⁸Ga-DOTATOC (SomaKIT TOC) 2 MBq/kg±10% (range 100-200 MBq) in patients with biopsy-proven grade 1-2 GEP-NETs. PET-CT was performed post injection. Patients were followed up for 28 days. We next implemented this new synthesis methodology in a clinical service assessed over 11 months.

RESULTS

Twenty consenting patients were recruited; 14 males, 6 females; mean (SD) age 58 years (12); NET grade 1 (70%), grade 2 (30%); and 75% with stage IV disease. Twelve patients experienced at least one adverse event (AE) during the study with no grade 3-4 toxicities. Only four AEs were classified as possibly (headache (n=1; 4%), nausea (1; 4%)) or probably (dysgeusia (1; 4%), paraesthesia (1; 4%)) related to the study preparation. One hundred thirteen vials of ⁶⁸Ga-DOTATOC (SomaKIT TOC) were synthesised with the 'kit' over a period of 11 months for clinical utility. Only 2/113 vials (1.77%) were rejected.

CONCLUSIONS

The new ready-to-use preparation of ⁶⁸Ga-DOTATOC (SomaKIT TOC) for injection was safe and well tolerated. This has led to the world's first (EMA) licensed ⁶⁸Ga-DOTATOC (SomaKIT TOC) radiopharmaceutical for the utility of PET imaging in patients with NETs. This preparation can be robustly implemented into routine clinical practice.

Prognostic Threshold for Circulating Tumor Cells in Patients With Pancreatic and Midgut Neuroendocrine Tumors

BACKGROUND

Circulating tumor cells (CTCs) are detectable in patients with neuroendocrine tumors (NETs) and are accurate prognostic markers although the optimum threshold has not been defined.

OBJECTIVE

This work aims to define optimal prognostic CTC thresholds in PanNET and midgut NETs.

PATIENTS AND METHODS

CellSearch was used to enumerate CTCs in 199 patients with metastatic pancreatic (PanNET) (90) or midgut NETs (109). Patients were followed for progression-free survival (PFS) and overall survival (OS) for a minimum of 3 years or until death.

RESULTS

The area under the receiver operating characteristic curve (AUROC) for progression at 12 months in PanNETs and midgut NETs identified the optimal CTC threshold as 1 or greater and 2 or greater, respectively. In multivariate logistic regression analysis, these thresholds were predictive for 12-month progression with an odds ratio (OR) of 6.69 (P < .01) for PanNETs and 5.88 (P < .003) for midgut NETs. The same thresholds were found to be optimal for predicting death at 36 months, with an OR of 2.87 (P < .03) and 5.09 (P < .005) for PanNETs and midgut NETs, respectively. In multivariate Cox hazard regression analysis for PFS in PanNETs, 1 or greater CTC had a hazard ratio (HR) of 2.6 (P < .01), whereas 2 or greater CTCs had an HR of 2.25 (P < .01) in midgut NETs. In multivariate analysis OS in PanNETs, 1 or greater CTCs had an HR of 3.16 (P < .01) and in midgut NETs, 2 or greater CTCs had an HR of 1.73 (P < .06).

CONCLUSIONS

The optimal CTC threshold to predict PFS and OS in metastatic PanNETs and midgut NETs is 1 and 2, respectively. These thresholds can be used to stratify patients in clinical practice and clinical trials.

Transcriptomic Profiling of In Vitro Tumor-Stromal Cell Paracrine Crosstalk Identifies Involvement of the Integrin Signaling Pathway in the Pathogenesis of Mesenteric Fibrosis in Human Small Intestinal Neuroendocrine Neoplasms

Aim

Analysis of the pathophysiology of mesenteric fibrosis (MF) in small intestinal neuroendocrine tumors (SI-NETs) in an in vitro paracrine model and in human SI-NET tissue samples.

Methods

An indirect co-culture model of SI-NET cells KRJ-I and P-STS with stromal cells HEK293 was designed to evaluate the paracrine effects on cell metabolic activity, gene expression by RT2 PCR Profilers to analyse cancer and fibrosis related genes, and RNA sequencing. The integrin signaling pathway, a specific Ingenuity enriched pathway, was further explored in a cohort of human SI-NET tissues by performing protein analysis and immunohistochemistry.

Results

RT Profiler array analysis demonstrated several genes to be significantly up- or down-regulated in a cell specific manner as a result of the paracrine effect. This was further confirmed by employing RNA sequencing revealing multiple signaling pathways involved in carcinogenesis and fibrogenesis that were significantly affected in these cell lines. A significant upregulation in the expression of various integrin pathway – related genes was identified in the mesenteric mass of fibrotic SI-NET as confirmed by RT-qPCR and immunohistochemistry. Protein analysis demonstrated downstream activation of the MAPK and mTOR pathways in some patients with fibrotic SI-NETs.

Conclusion

This study has provided the first comprehensive analysis of the crosstalk of SI-NET cells with stromal cells. A novel pathway – the integrin pathway – was identified and further validated and confirmed in a cohort of human SI-NET tissue featured by a dual role in fibrogenesis/carcinogenesis within the neoplastic fibrotic microenvironment.

Cardiac Metastases in Patients with Neuroendocrine Tumours: Clinical Features, Therapy Outcomes, and Prognostic Implications

BACKGROUND

Cardiac metastases (CM) from neuroendocrine tumours (NET) are rare; however, with the introduction of new molecular imaging modalities, such as 68Ga-DOTATATE PET-CT for NET diagnosis and re-staging, they are now identified more frequently. This study presents a single-institution experience on the NET CM characteristics, management, and prognostic implications.

METHODS

Between January 1998 and January 2020, 25 NET patients with CM were treated in our unit. A retrospective review of electronic records was performed. Overall survival (OS) was assessed by the Kaplan-Meier method. Cox regression models were used to evaluate the association of various clinical variables with OS.

RESULTS

The median age in the NET CM cohort was 64 years, with small intestine being the most common primary (84%). Nearly half of the patients suffered either from shortness of breath (48%) or had palpitations (12%). Peptide receptor radionuclide therapy (PRRT) was applied in more than half of the patients (64%), who had an improved trend for a longer median OS compared to those patients who did not receive PRRT (76.0 vs. 14.0 months, p = 0.196). The multivariate analysis demonstrated that concomitant skeletal or pancreatic metastases, as well as N-terminal pro-B-type natriuretic peptide (NT pro-BNP) >2 × upper limit of normal (ULN), were independent poor prognosticators.

CONCLUSIONS

Clinical features of NET CM ranged from asymptomatic patients to heart failure. Concomitant bone or pancreatic metastases and NT pro-BNP levels >2 ULN predicted shorter survival time. PRRT serves as a feasible therapy with promising survival benefits; however, more data are needed.

Antiproliferative Effect of Above-Label Doses of Somatostatin Analogs for the Management of Gastroenteropancreatic Neuroendocrine Tumors

BACKGROUND

Above-label doses of somatostatin analogs (SSAs) are increasingly utilized in the management of inoperable/metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NETs), progressing on standard 4-weekly regimens.

OBJECTIVE

To evaluate the antiproliferative effect of 3-weekly SSA administration in a retrospective GEP-NET cohort.

METHODS

Patients with advanced GEP-NET, treated with long-acting release (LAR) octreotide 30 mg or lanreotide Autogel 120 mg at a 3-weekly interval, after disease progression on standard 4-weekly doses, were retrospectively identified. Clinicopathologic and treatment response data were collected. Progression-free survival (PFS; dose escalation to radiographic progression or death) was estimated with the Kaplan-Meier method. Factors associated with PFS were identified with the Cox proportional-hazards model.

RESULTS

The inclusion criteria were fulfilled by 105 patients. Octreotide LAR was administered to 60 (57%) and lanreotide Autogel to 45 (43%). Indications for dose escalation were breakthrough carcinoid symptoms (58%), radiographic progression (35%) and/or increasing biomarkers (11%). Diarrheal and/or flushing symptomatic improvement was identified in 37/67 cases (55%) and 30/55 cases (55%) with available data, respectively. The disease control rate (radiographic partial response or stable disease) was achieved in 53 patients (50%). Median PFS was 25.0 months (95% CI 16.9-33.1). Patients with radiographic progression <12 months from 4-weekly SSA initiation had worse PFS after dose escalation (7.0 vs. 17.0 months, p = 0.002). In multivariate analysis, pancreatic NETs, a Ki-67 index ≥5% and multiple extrahepatic metastases were independently associated with inferior PFS.

CONCLUSIONS

Above-label doses of SSAs may offer a considerable prolongation of PFS and could be utilized as a bridge to other more toxic treatments. Patients with small bowel/colorectal primaries, a Ki-67 index <5% and absence of/limited extrahepatic metastases are more likely to benefit from this approach.

Management of Asymptomatic Sporadic Nonfunctioning Pancreatic Neuroendocrine Neoplasms (ASPEN) ≤2 cm: Study Protocol for a Prospective Observational Study

Introduction: The optimal treatment for small, asymptomatic, nonfunctioning pancreatic neuroendocrine neoplasms (NF-PanNEN) is still controversial. European Neuroendocrine Tumor Society (ENETS) guidelines recommend a watchful strategy for asymptomatic NF-PanNEN <2 cm of diameter. Several retrospective series demonstrated that a non-operative management is safe and feasible, but no prospective studies are available. Aim of the ASPEN study is to evaluate the optimal management of asymptomatic NF-PanNEN ≤2 cm comparing active surveillance and surgery.

Methods: ASPEN is a prospective international observational multicentric cohort study supported by ENETS. The study is registered in ClinicalTrials.gov with the identification code NCT03084770. Based on the incidence of NF-PanNEN the number of expected patients to be enrolled in the ASPEN study is 1,000 during the study period (2017–2022). Primary endpoint is disease/progression-free survival, defined as the time from study enrolment to the first evidence of progression (active surveillance group) or recurrence of disease (surgery group) or death from disease. Inclusion criteria are: age >18 years, the presence of asymptomatic sporadic NF-PanNEN ≤2 cm proven by a positive fine-needle aspiration (FNA) or by the presence of a measurable nodule on high-quality imaging techniques that is positive at ⁶⁸Gallium DOTATOC-PET scan.

Conclusion: The ASPEN study is designed to investigate if an active surveillance of asymptomatic NF-PanNEN ≤2 cm is safe as compared to surgical approach.

Molecular profiling of neuroendocrine tumours to predict response and toxicity to peptide receptor radionuclide therapy

Peptide receptor radionuclide therapy (PRRT) is a type of radiotherapy that targets peptide receptors and is typically used for neuroendocrine tumours (NETs). Some of the key challenges in its use are the prediction of efficacy and toxicity, patient selection, and response optimisation. In this Review, we assess current knowledge on the molecular profile of NETs and the strategies and tools used to predict, monitor, and assess the toxicity of PRRT. The few mutations in tumour genes that can be evaluated (eg, ATM and DAXX) are limited to pancreatic NETs and are most likely not informative. Assays that are transcriptomic or based on genes are effective in the prediction of radiotherapy response in other cancers. A blood-based assay for eight genes (the PRRT prediction quotient [PPQ]) has an overall accuracy of 95% for predicting responses to PRRT in NETs. No molecular markers exist that can predict the toxicity of PRRT. Candidate molecular targets include seven single nucleotide polymorphisms (SNPs) that are susceptible to radiation. Transcriptomic evaluations of blood and a combination of gene expression and specific SNPs, assessed by machine learning with algorithms that are tumour-specific, might yield molecular tools to enhance the efficacy and safety of PRRT.

Home Total Parenteral Nutrition for Intestinal Failure in Patients with Advanced Small Intestinal Neuroendocrine Neoplasms

The role of total parenteral nutrition (TPN) in cancer patients is controversial, but it may be a treatment option for some patients with indolent but advanced small intestinal neuroendocrine neoplasms (SI-NENs). The aim of this study is to investigate whether home TPN was associated with long-term survival and to assess the indications, duration and complications of TPN in patients with advanced SI-NENs. Patients with advanced SI-NENs who received home TPN were retrospectively included. Electronic records were reviewed for clinical information. Five patients receiving home TPN were identified out of 1011 patients with SI-NENs in our center. The median duration of TPN administration was 12 mo. Small bowel obstruction was the most common reason for TPN initiation. TPN-related complications included two catheter infections, one thrombosis and one episode of TPN-related transaminitis. At the last follow-up, three patients had died and two were alive. The median survival was 12 mo. Overall estimated 1-yr probability of survival on home TPN by Kaplan-Meier analysis was 40%. In conclusion, home TPN may be a treatment option in highly selected advanced SI-NEN patients with severe gastrointestinal tract dysfunction. The initiation of home TPN is associated with long-term survival (≥1 yr), and complication rates appear acceptable.

Evaluation of circulating transcript analysis (NETest) in small intestinal neuroendocrine neoplasms after surgical resection

PURPOSE

Surgical resection is the only effective curative strategy for small intestinal neuroendocrine neoplasms (SINENs). Nevertheless, the evaluation of residual disease and prediction of disease recurrence/progression remains a problematic issue.

METHODS

We evaluated 13 SINENs that underwent surgical resection of the primary tumour and/or mesenteric mass. Patients were divided in three groups: (a) Group 1: SINENs that underwent resection with curative intent, (b) Group 2: SINENs treated with resection in the setting of metastatic disease, which remained stable and (c) Group 3: SINENs treated with resection in the setting of metastatic disease, with evidence of any progression at follow-up. NETest and chromogranin A were measured pre-operatively and post-operatively during a 22-month median follow-up period and compared with imaging studies. NETest score <20% was determined as normal, 20-40% low, 41-79% intermediate and ≥80% high score.

RESULTS

NETest score was raised in all (100%) SINENs pre-operatively. Surgery with curative intent resulted in NETest score reduction from 78.25 ± 15.32 to 25.25 ± 1.75 (p < 0.05). Low NETest scores post-operatively were evident in all cases without clinical evidence of residual disease (Group 1). However, the low disease activity score suggested the presence of microscopic residual disease. In three cases (75%) with stable disease (Group 2) the NETest score was low consistent with indolent disease. In the progressive disease group (Group 3), a high NETest score was present in three cases (60%) and an intermediate NETest score in the remainder (40%).

CONCLUSIONS

Blood NETest scores accurately identified SINENs and were significantly decreased by curative surgery. Monitoring NETest post-operatively may facilitate management by identifying the presence of residual/progressive disease.

Impact of liver tumour burden, alkaline phosphatase elevation, and target lesion size on treatment outcomes with 177Lu-Dotatate: an analysis of the NETTER-1 study

PURPOSE

To assess the impact of baseline liver tumour burden, alkaline phosphatase (ALP) elevation, and target lesion size on treatment outcomes with ¹⁷⁷Lu-Dotatate.

METHODS

In the phase 3 NETTER-1 trial, patients with advanced, progressive midgut neuroendocrine tumours (NET) were randomised to 177Lu-Dotatate (every 8 weeks, four cycles) plus octreotide long-acting release (LAR) or to octreotide LAR 60 mg. Primary endpoint was progression-free survival (PFS). Analyses of PFS by baseline factors, including liver tumour burden, ALP elevation, and target lesion size, were performed using Kaplan-Meier estimates; hazard ratios (HRs) with corresponding 95% CIs were estimated using Cox regression.

RESULTS

Significantly prolonged median PFS occurred with ¹⁷⁷Lu-Dotatate versus octreotide LAR 60 mg in patients with low (< 25%), moderate (25-50%), and high (> 50%) liver tumour burden (HR 0.187, 0.216, 0.145), and normal or elevated ALP (HR 0.153, 0.177), and in the presence or absence of a large target lesion (diameter > 30 mm; HR, 0.213, 0.063). Within the ¹⁷⁷Lu-Dotatate arm, no significant difference in PFS was observed amongst patients with low/moderate/high liver tumour burden (P = 0.7225) or with normal/elevated baseline ALP (P = 0.3532), but absence of a large target lesion was associated with improved PFS (P = 0.0222). Grade 3 and 4 liver function abnormalities were rare and did not appear to be associated with high baseline liver tumour burden.

CONCLUSIONS

¹⁷⁷Lu-Dotatate demonstrated significant prolongation in PFS versus high-dose octreotide LAR in patients with advanced, progressive midgut NET, regardless of baseline liver tumour burden, elevated ALP, or the presence of a large target lesion. Clinicaltrials.gov : NCT01578239, EudraCT: 2011-005049-11.

Clinicopathological correlations of mesenteric fibrosis and evaluation of a novel biomarker for fibrosis detection in small bowel neuroendocrine neoplasms

PURPOSE

Mesenteric fibrosis (MF) in small intestinal neuroendocrine neoplasms (SINENs) is often associated with significant morbidity and mortality. The detection of MF is usually based on radiological criteria, but no previous studies have attempted a prospective, multidimensional assessment of mesenteric desmoplasia to determine the accuracy of radiological measurements. There is also a lack of non-invasive biomarkers for the detection of image-negative MF.

METHODS

A multidimensional assessment of MF incorporating radiological, surgical and histological parameters was performed in a prospective cohort of 34 patients with SINENs who underwent primary resection. Pre-operative blood samples were collected in 20 cases to evaluate a set of five profibrotic circulating transcripts-the "fibrosome"-that is included as an "omic" component of the NETest.

RESULTS

There was a significant correlation between radiological and surgical assessments of MF (p < 0.05). However, there were several cases of image-negative MF. The NETest-fibrosome demonstrated an accuracy of 100% for the detection of microscopic MF.

CONCLUSIONS

The detection of MF by radiological criteria has limitations. The NETest-fibrosome is a promising biomarker for fibrosis detection and further validation of these results would be needed in larger, multicentre studies.

Orbital metastases from neuroendocrine neoplasms: clinical implications and outcomes

PURPOSE

Neuroendocrine neoplasms (NENs) may rarely metastasise to the orbit. Published data on epidemiology, incidence and preferred treatment is limited. We present the largest cohort of symptomatic and asymptomatic NEN patients with orbital metastases and data on epidemiological parameters, symptoms as well as diagnostic/treatment modalities used.

METHODS

We identified patients from our internal NEN database of patients who had also undergone Gallium⁶⁸-DOTATATE PET (Ga⁶⁸-DOTA). The diagnosis of orbital metastatic NEN was made on somatostatin receptor imaging and confirmed on a dedicated MRI of orbits.

RESULTS

We identified 27 patients of 994 patients evaluated with Ga⁶⁸-DOTATATE PET imaging during their surveillance monitoring in our department; 15 female, average age at NEN diagnosis 53 years and orbital metastatic NEN diagnosis 59 years. The majority of NEN primaries originated from small bowel (18/27, 66.4%) or pancreas 4/27 (4/27, 14.8%). Hepatic with or without concomitant skeletal metastases were present in 23/27 (85%) of patients. Ocular symptoms and/or signs were evident in 11/27 (41%) of patients. 5/11 symptomatic patients underwent external beam radiotherapy (EBRT) resulting in complete symptoms resolution. The 5-year survival was estimated at 84.1%.

CONCLUSIONS

Orbital metastases of NEN have a relatively low prevalence, more commonly associated with small bowel primary. Extraocular muscles are primarily affected, irrespectively of liver disease burden. Survival does not seem to be affected. EBRT is an efficacious treatment modality for both symptom relief and tumour growth control. Administration of peptide receptor radionuclide therapy may occasionally induce temporary ocular symptoms, which resolve following treatment with a short course of steroids.

Predictors of antiproliferative effect of lanreotide autogel in advanced gastroenteropancreatic neuroendocrine neoplasms

PURPOSE

The antiproliferative properties of lanreotide autogel (LAN) in gastroenteropancreatic neuroendocrine neoplasms (GEP NENs) were demonstrated in the CLARINET study. However, there is limited literature regarding factors that affect progression-free survival (PFS) in patients with GEP NENs treated with LAN.

METHODS

We identified a total of 191 treatment-naive patients with advanced GEP NENs and positive SSTR uptake on imaging (Octreoscan or ⁶⁸Gallium DOTATATE Positron Emission Tomography [⁶⁸GaPET]) who received first-line LAN monotherapy, albeit at various starting doses (60, 90 or 120 mg/month). A group of 102 patients who initiated treatment at the standard dose of 120 mg/month were included in the study and further evaluated by univariate and multivariate analyses to identify predictors of PFS.

RESULTS

The location of tumour primary was in the small bowel in 63 (62%), pancreas in 31 (30%) and colon/rectum in 8 patients (8%). The tumours were well-differentiated, and the majority were grade 1 (52%), or 2 (38%). About 60% of cases had progressive disease at the time of treatment initiation. Most patients with available pretreatment nuclear medicine imaging (Octreoscan or ⁶⁸Ga PET) had a Krenning score of 3 (44%) or 4 (50%). The median PFS for the entire cohort was 19 months (95% CI 12, 26 months). The univariate analysis demonstrated that grade 2 tumours, progressive disease at baseline and metastatic liver disease were associated with a significantly shorter PFS, while other evaluated variables did not affect PFS at a statistically significant level. However, at multivariate analysis only the tumour grade remained statistically significant.

CONCLUSIONS

The current study showed that, of many evaluated variables, only the tumour grade was predictive of PFS duration and this should be considered during patient selection for treatment.

Endoscopic ultrasound-guided fine-needle aspiration vs fine-needle biopsy for the diagnosis of pancreatic neuroendocrine tumors

Background and study aims  Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) as a method of obtaining preoperative diagnosis of pancreatic neuroendocrine tumors (PanNETs) has been reported in several series. Fine-needle biopsies (FNB) are increasingly employed to obtain core specimens during EUS. However, the differences in efficacy between these sampling methods in the diagnosis of PanNETs still needs to be defined. Patients and methods  Over a 13-year period, all patients who underwent EUS-guided tissue sampling of suspicious pancreatic lesions with clinical, endoscopic and pathologic details were entered into an electronic database. Lesions underwent EUS-FNA or FNB sampling, or a combination of the two. The accuracy and safety of different EUS-guided sampling methods for confirmed PanNETs were investigated. Results  A total of 91 patients (M/F: 42/49, median age: 57 years), who underwent 102 EUS procedures had a final diagnosis of PanNET. Both EUS-guided sampling modalities were used in 28 procedures, EUS-FNA alone was used in 61 cases, while EUS-FNB alone in 13 cases. Diagnostic yield of EUS-FNA and EUS-FNB alone, including the inadequate specimens, was 77.5 % (95 %CI: 68.9 - 86.2 %) and 85.4 % (95 %CI: 74.6 - 96.2 %), respectively. The combination of both sampling modalities established the diagnosis in 96.4 % of cases (27/28) (95 %CI: 89.6 - 100 %), significantly superior to EUS-FNA alone ( P  = 0.023). Diagnostic sensitivity among the adequate samples for EUS-FNA, EUS-FNB and for the combination of the two methods was 88.4 % (95 %CI: 80.9 - 96.0 %), 94.3 % (95 %CI: 86.6 - 100 %) and 100 % (95 %CI: 100 - 100 %). There was one reported complication, a post-FNA bleeding, treated conservatively. Conclusions  EUS-FNB improves diagnostic sensitivity and confers additional information to cytological assessment of PanNETs.

Evaluation of meaningful change in bowel movement frequency for patients with carcinoid syndrome

Background

Carcinoid syndrome is associated with a reduced quality of life that can be attributed to symptoms such as diarrhea and fatigue as well as social and financial issues. This study was conducted to psychometrically assess meaningful change in bowel movement frequency among carcinoid syndrome patients using data from the TELESTAR clinical study.

Methods

An anchor-based approach for deriving meaningful change thresholds consisted of mapping change from baseline bowel movement frequency to other patient-reported assessments of change. These included the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire - Core Questionnaire (QLQ-C30) Diarrhea Symptom responders, the EORTC Gastrointestinal NET questionnaire (GI.NET21) GI Symptom responders, and reported adequate relief at Week 12 (≥ 10-point score decrease from Day 1 to Week 12). Parameters included within-group mean change from baseline to Week 12, t-tests of the change (Wilcoxon rank sum for adequate relief), and effect size.

Results

There were 135 carcinoid syndrome patients with a mean baseline frequency of 5.7 bowel movements a day. A distribution-based method yielded meaningful change estimates of 0.62 bowel movements a day for overall frequency and 0.83 bowel movements a day at Week 12. Anchor-based analysis indicated a large effect size among patients who reported adequate relief at Week 12 (− 1.58; n = 18; P = 0.014), the QLQ-C30 Diarrhea domain responders (− 1.24; n = 40; P < 0.001), and the GI.NET21 GI Symptoms Domain responders (− 1.49; n = 25; P = 0.005). Exit interview data for meaningful change yielded effect size estimates of − 1.57 for overall change during the Double-blind Treatment Period and − 1.97 for change between Baseline and Week 12.

Conclusions

Meaningful change derivation is critical to interpret patient outcomes for evaluating treatment efficacy. In this study, carcinoid syndrome patients experienced clinically meaningful reductions in bowel movement frequency of ≥30% over 12 weeks with telotristat ethyl treatment.

Trial registration

NCT01677910.

Unmet needs in the international neuroendocrine tumor (NET) community: Assessment of major gaps from the perspective of patients, patient advocates and NET health care professionals

Due to the increasing incidence and prevalence of neuroendocrine tumors (NETs), there is a need to assess any gaps in awareness and care. A survey was undertaken in 2017 to identify perceived unmet needs from the perspectives of patients/families, patient advocates and health care professionals (HCPs). The survey consisted of 33–37 questions (depending on type of respondent) across four areas: information, care, treatments and research. In total, 443 participants from 26 countries responded: 338 patients/families, 35 advocates and 70 HCPs. Perceived unmet needs regarding provision of information at diagnosis differed between groups. While 59% of HCPs believed they provided sufficient information, informational needs were mostly/fully met for only 30% of patients and 18% of advocates. Additionally, 91% of patients and 97% of advocates felt that patients had to search for information themselves. Availability of Gallium‐68‐Dotatate PET/CT scan was limited for the majority of patients (patients: 73%; advocates: 85%; HCP: 86%), as was access to treatments, particularly peptide receptor radionuclide therapy (patients: 42%; advocates: 95%; HCPs: 77%). All groups felt that standards of care, including psychological needs and diagnosis of mental health, were not fully met. Although about two‐thirds of patients were managed by a multidisciplinary team, 14% of patients reportedly did not have enough contact. All groups supported more patient involvement in research; patients and advocates prioritized improvement in diagnosis and HCPs focused on clinical trials. This survey revealed significant unmet needs but differing perceptions regarding these among the groups. There is a need for investigation and collaboration to improve standards of care for NET patients.

What's new?

Even though the incidence of neuroendocrine tumors (NETs) has been rising worldwide, the current management of patients varies considerably, potentially leaving many with suboptimal care. An international survey was carried out in 2017 to investigate unmet needs in the NET patient community. The survey revealed that patients perceive numerous unmet needs in key areas including provision of information, diagnostics and treatment access, care standards, and research involvement. While healthcare professionals were aware of these gaps, they generally underestimated their magnitude. Patients and healthcare professionals need to work together to improve the lives and prospects of the increasing numbers of patients.

The role of 5-hydroxyindoleacetic acid in neuroendocrine tumors: the journey so far

5-Hydroxyindole acetic acid (5-HIAA) is a surrogate marker for serotonin measurement and one of the first biochemical markers used in neuroendocrine tumors. In this review, we give a brief history of 5-HIAA and its precursor serotonin. We discuss its clinical utility and diagnostic performance in small intestinal neuroendocrine tumor and describe the challenges encountered during its analysis, historically performed in urine. The introduction of blood-based assays will help overcome some of the issues associated with its measurement in urine. The diagnostic performance of serum and plasma 5-HIAA has been shown to be comparable to that of urine 5-HIAA. Thus, analysis in either serum or plasma will provide a practical and convenient alternative to urine.

Analysis of patient diaries in the NETTER-1 Study of 177Lu-DOTATATE versus high-dose octreotide in progressive midgut neuroendocrine tumors

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Background: The primary statistical analysis for the NETTER-1 trial showed a clinically and statistically significant PFS benefit with 177Lu-DOTATATE vs. high-dose octreotide. 177Lu-DOTATATE treatment was also correlated with a significant delay in time to deterioration in HRQoL. In addition to HRQoL questionnaires, patients were asked to record presence or absence of a range of symptoms in a daily diary. Methods: A Mixed Model Repeated Measures (MMRM) was used to analyze the change, compared to baseline, of the occurrence of abdominal Pain, diarrhea and cutaneous flushing as these symptoms were regarded as the most relevant to judge the overall disease status. For each visit (week = 0, 4, 8, etc.) the number of days with symptoms during the previous period was calculated. At baseline, the number of days with symptoms was counted over the previous 6 weeks, whereas the time frame between visits lasted 4 weeks. Results: The estimated number of days with symptoms declined significantly more in the 177Lu-dotatate arm compared to the octreotide arm. The difference in change and the confidence intervals for the symptoms abdominal pain, diarrhea and flushing of skin are, respectively: -3.11 [-4.88; -1.34], -3.11 [-5.04; -1.18] and -1.98 [-3.88; -0.08]. Conclusions: Analysis of symptom diaries confirms that 177Lu-Dotatate can palliate clinically relevant symptoms when compared to high-dose octreotide.

Circulating tumour cells and their association with bone metastases in patients with neuroendocrine tumours

Background

Bone metastases are associated with a worse outcome in patients with neuroendocrine tumours (NETs). Tumour overexpression of C-X-C chemokine receptor 4 (CXCR4) appears predictive of skeletal involvement. We investigated the role of circulating tumour cells (CTCs) and CXCR4 expression on CTCs as potential predictors of skeleton invasion.

Methods

Blood from patients with metastatic bronchial, midgut or pancreatic NET (pNET) was analysed by CellSearch. CXCR4 immunohistochemistry was performed on matched formalin-fixed paraffin-embedded (FFPE) samples.

Results

Two hundred and fifty-four patients were recruited with 121 midgut and 119 pNETs, of which 51 and 36% had detectable CTCs, respectively. Bone metastases were reported in 30% of midgut and 23% of pNET patients and were significantly associated with CTC presence (p = 0.003 and p < 0.0001). In a subgroup of 40 patients, 85% patients with CTCs had CTCs positive for CXCR4 expression. The proportion of CXCR4-positive CTCs in patients with bone metastases was 56% compared to 35% in those without (p = 0.18) it. Staining for CXCR4 on matched FFPE tissue showed a trend towards a correlation with CXCR4 expression on CTCs (p = 0.08).

Conclusions

CTC presence is associated with bone metastases in NETs. CXCR4 may be involved in CTC osteotropism and present a therapeutic target to reduce skeletal morbidity.

Challenging the Current Risk Factors of Appendiceal Neuroendocrine Neoplasms: Can They Accurately Predict Local Lymph Nodal Invasion? Results from a Large Case Series

BACKGROUND

Appendiceal neuroendocrine neoplasms (ANEN) are uncommon entities, which run mostly an indolent course. Appendicectomy alone is usually curative, except for in a selected group of patients that are deemed to be at risk of loco-regional metastases, in whom a completion right hemicolectomy (RHC) is recommended. The current "Guidelines" criteria for the latter have been controversial, and may result in overtreatment, which is concerning for a young patient population.

OBJECTIVE

The aim of this study is to evaluate the prognostic value of the current criteria in identifying more accurately those at-risk patients.

METHODS

This was a retrospective study of the 263 cases of ANEN referred for advice or management to a tertiary referral unit over a 10-year period. Seventy-two patients underwent RHC, based on criteria, suggested by International Guidelines. Each one of those was assessed to identify whether it correlated with lymph node invasion (LNI) at the RHC surgical specimen.

RESULTS

Tumour grade (p < 0.001), vascular (p = 0.044) and lymph vessel invasion (p < 0.001) were all found to be statistically significant independent risk factors for LNI identified following RHC, whilst tumour size (p = 0.375) and mesoappendiceal invasion (MAI) (p = 0.317) were not statistically significant. However, deep MAI and tumour size >2 cm showed a correlation with each other on LNI positive subgroup analysis. Location in appendiceal base made LNI more likely but again was not significant (p = 0.133).

CONCLUSIONS

Higher tumour grade and lymphovascular invasion should be considered as the most important risk prognosticators. Surprisingly, tumour size was not found to be significant in our cohort. Further international multicentre studies with large numbers of patients are needed to fully validate those data.