Anti-tumoral effects of somatostatin analogs: a lesson from the CLARINET study

Neuroendocrine neoplasms in the context of inherited tumor syndromes: a reappraisal focused on targeted therapies

PURPOSE

Neuroendocrine neoplasms can occur as part of inherited disorders, usually in the form of well-differentiated, slow-growing tumors (NET). The main predisposing syndromes include: multiple endocrine neoplasias type 1 (MEN1), associated with a large spectrum of gastroenteropancreatic and thoracic NETs, and type 4 (MEN4), associated with a wide tumour spectrum similar to that of MEN1; von Hippel-Lindau syndrome (VHL), tuberous sclerosis (TSC), and neurofibromatosis 1 (NF-1), associated with pancreatic NETs. In the present review, we propose a reappraisal of the genetic basis and clinical features of gastroenteropancreatic and thoracic NETs in the setting of inherited syndromes with a special focus on molecularly targeted therapies for these lesions.

METHODS

Literature search was systematically performed through online databases, including MEDLINE (via PubMed), and Scopus using multiple keywords' combinations up to June 2022.

RESULTS

Somatostatin analogues (SSAs) remain the mainstay of systemic treatment for NETs, and radiolabelled SSAs can be used for peptide-receptor radionuclide therapy for somatostatin receptor (SSTR)-positive NETs. Apart of these SSTR-targeted therapies, other targeted agents have been approved for NETs: the mTOR inhibitor everolimus for lung, gastroenteropatic and unknown origin NET, and sunitinib, an antiangiogenic tyrosine kinase inhibitor, for pancreatic NET. Novel targeted therapies with other antiangiogenic agents and immunotherapies have been also under evaluation.

CONCLUSIONS

Major advances in the understanding of genetic and epigenetic mechanisms of NET development in the context of inherited endocrine disorders have led to the recognition of molecular targetable alterations, providing a rationale for the implementation of treatments and development of novel targeted therapies.

Physician-perceived utility of the EORTC QLQ-GINET21 questionnaire in the treatment of patients with gastrointestinal neuroendocrine tumours: a multicentre, cross-sectional survey (QUALINETS)

Background and objective

Patient-reported outcome measures can provide clinicians with valuable information to improve doctor-patient communication and inform clinical decision-making. The aim of this study was to evaluate the physician-perceived utility of the QLQ-GINET21 in routine clinical practice in patients with gastrointestinal neuroendocrine tumours (GI-NETs). Secondary aims were to explore the patient, clinician, and/or centre-related variables potentially associated with perceived clinical utility.

Methods

Non-interventional, cross-sectional, multicentre study conducted at 34 hospitals in Spain and Portugal (NCT02853422). Patients diagnosed with GI-NETs completed two health-related quality of life (HRQoL) questionnaires (QLQ-C30, QLQ-GINET21) during a single routine visit. Physicians completed a 14-item ad hoc survey to rate the clinical utility of QLQ-GINET21 on three dimensions: 1)therapeutic and clinical decision-making, 2)doctor-patient communication, 3)questionnaire characteristics.

Results

A total of 199 patients at 34 centres were enrolled by 36 participating clinicians. The highest rated dimension on the QLQ-GINET21 was questionnaire characteristics (86.9% of responses indicating “high utility”), followed by doctor-patient communication (74.4%), and therapeutic and clinical decision-making (65.8%). One physician-related variable (GI-NET patient volume > 30 patients/year) was associated with high clinical utility and two variables (older age/less experience treating GI-NETs) with low clinical utility.

Conclusions

Clinician-perceived clinical utility of QLQ-GINET21 is high. Clinicians valued the instruments’ capacity to provide a better understanding of patient perspectives and to identify the factors that had the largest influence on patient HRQoL.

Meta-Analysis of Randomized Clinical Trials Comparing Active Treatment with Placebo in Metastatic Neuroendocrine Tumors

BACKGROUND

Most guidelines still recommend active surveillance for patients with asymptomatic, unresectable neuroendocrine tumors (NETs). However, recent findings from several randomized placebo-controlled trials suggest that most patients would benefit from active treatment. We conducted a meta-analysis of pooled outcomes from clinical trials in which an active treatment arm was compared with placebo to determine whether active treatment provides a survival advantage.

MATERIALS AND METHODS

This meta-analysis evaluated six trials that compared a medication with placebo in patients with an asymptomatic, metastatic NET. The trials were heterogenous with regard to the active medication (octreotide, lanreotide, sunitinib, everolimus, Lu-Dotatate) and tumor localizations (gastrointestinal, pancreas, lung). Overall survival (OS) and progression-free survival (PFS) for the placebo and active treatment arms were obtained from individual trial data and combined to obtain pooled outcomes.

RESULTS

The individual trials all reported significantly better PFS outcomes for active treatment. The pooled data confirmed this advantage. At months 3, 6, 12, 18, and 24, pooled PFS rates for the placebo and treatment arms, respectively, were 92.9% versus 96.9%; 54.3% versus 83.7%; 35.5% versus 68.5%; 25.1% versus 54.7%; and 17.7% versus 61.0%. OS was also higher in the active treatment groups. At months 6, 12, 24, 36, 48, and 60, OS rates (placebo vs. active treatment), respectively, were 88.1% versus 93.4%; 84.1% versus 86.2%; 67.4% versus 76%; 56.6% versus 64.4%; 49.9% versus 61.0%; and 41.7% versus 45.9%.

CONCLUSION

This meta-analysis confirms findings from recent clinical trials indicating that active treatment yields better survival outcomes than placebo. Importantly, these findings were obtained across a wide range of patient profiles and diverse medical treatments for metastatic NETs. Given the lack of reliable prognostic factors to determine a priori which patients are unlikely to benefit from active treatment, these findings support early treatment in most patients.

IMPLICATIONS FOR PRACTICE

Although most guidelines still recommend active surveillance for patients diagnosed with metastatic neuroendocrine tumors, the results of this meta-analysis, together with recent data from key clinical trials, suggest that most patients could benefit from upfront active treatment. However, more data are needed to confirm this.