Prognostic impact of tumour burden in stage IV neuroendocrine neoplasia: A comparison between pancreatic and gastrointestinal localizations.

BACKGROUND: Although prognosis of NENs is affected by several features including tumour burden, the specific role of this factor in pancreatic NENs (PanNENs) and gastrointestinal NENs (GI NENs) is not well established. AIM: To compare the prognostic role of tumour burden in PanNENs and GI NENs. PATIENTS AND METHODS: This study was a retrospective analysis of stage IV PanNENs and GI NENs. Tumours were classified based on liver tumour volume (<25% or >25%). Overall survival as assessed by Kaplan-Meier curves, and Cox proportional hazards method was used to perform risk factor analysis. RESULTS: The analysis included 300 patients, including 166 panNENs (55.3%) and 134 GI NENs (44.7%). A total of 158 patients (52.7%) had G2 tumours, 107 had G1 tumours (35.7%), and 35 had G3 tumours (11.6%). Tumour liver involvement >25% was observed in 187 patients (62.3%): 106 PanNENs (56.7%), and 81 GI NENs (43.3%) (p = 0.551). Bone metastases were present in 45 patients (15%): 22 PanNENs (13.2%) and 23 GI NENs (17.1%) (p = 0.416). Characteristics of the PanNENs, including: grading (G2 vs G1, HR = 3.7; G3 vs G1, HR = 16.40), liver involvement > 25% (HR = 3.09), and bone metastases (HR = 2.27) were independent predictors for poor survival, whereas the only significant risk factor in GI NENs was grading (G2 vs G1, HR = 4.36; G3 vs G1, HR = 8.60). CONCLUSIONS: PanNENs and GI NENs have different risk profiles. Liver tumour volume and the presence of bone metastases significantly affect survival in patients with PanNENs but has no impact on the clinical outcomes of GI NENs.

Effects of low-dose aspirin on clinical outcome and disease progression in patients with gastroenteropancreatic neuroendocrine neoplasm.

Objective: The chemopreventive effect of aspirin (ASA) has been observed in the setting of colorectal cancer and other solid neoplasms. Recently, ASA has demonstrated a promising anti-proliferative effect on GEP-NENs in vitro. However, the direct anti-neoplastic impact of ASA on GEP-NEN clinical outcome is yet to be clarified. Materials and methods: All the GEP-NEN patients followed up in three European Centers from January 2005 to September 2016 were retrospectively enrolled. Patients taking ASA in doses of 75-100 mg daily for cardiovascular prevention for at least six months were evaluated. The possible association between ASA and disease grading, staging, primary site, OS and PFS were evaluated. Results: Two hundred fifty one patients were included (117 males, median age 63 years). Of these, 64 patients were prescribed with ASA. No clear impact on OS or PFS was observed in GEP-NEN patients taking ASA compared to those not taking it. ASA intake was related with the patients' older age. At Cox multivariate analysis, stage IV and Ki-67 resulted independent predictors for OS and PFS. In the setting of intestinal NENs, a suggestive, but not statistically significant, protective role of ASA on PFS was observed [HR 0.41 (95% CI: 0.13-1.29)]. Conclusions: Despite ASA showed promising anti-proliferative effects in vitro and a chemopreventive action in NENs has been reported, a clear impact of ASA on survival in NENs has not emerged from the present study. However, in the subgroup of patients with small-intestine NENs, ASA showed a trend toward a protective role.

Treatment of Advanced Merkel Cell Carcinoma: Current Therapeutic Options and Novel Immunotherapy Approaches.

Advanced Merkel cell carcinoma (MCC) is a very aggressive, rare neuroendocrine tumor of the skin with a high frequency of locoregional recurrence and metastasis, and a high mortality rate. Surgical resection, sentinel lymph node biopsy, and radiotherapy represent the gold standard of treatment in patients with localized disease, while chemotherapy has a significant role in the treatment of advanced disease. However, no definitive evidence on the survival impact of radiotherapy in the advanced stages has been provided to date, and response to chemotherapy remains brief in the majority of cases, indicating an urgent need for alternative approaches. Biological and genome sequencing studies have implicated multiple molecular pathways in MCC, thus leading to the development of new agents that target angiogenic factors, anti-apoptosis molecules, poly-ADP ribose polymerase, intracellular signal proteins such as the PI3K/AKT/mTOR pathway, and peptide receptors such as somatostatin receptors. More recently, immunotherapy agents such as avelumab, pembrolizumab, and nivolumab, which act by blocking the programmed cell-death (PD)-1/PD-L1 immune checkpoint, have shown promising results, especially in the advanced setting, and should now be considered standard of care for metastatic MCC. Current research is focusing on developing new immunotherapeutic strategies, identifying predictive biomarker to aid in the selection of patients responsive to immunotherapy, and defining combination approaches to increase efficacy in refractory patients.

Metformin Use Is Associated With Longer Progression-Free Survival of Patients With Diabetes and Pancreatic Neuroendocrine Tumors Receiving Everolimus and/or Somatostatin Analogues.

BACKGROUND & AIMS: Metformin seems to have anticancer effects. However, it is not clear whether use of glycemia and metformin affect outcomes of patients with advanced pancreatic neuroendocrine tumors (pNETs). We investigated the association between glycemia and progression-free survival (PFS) of patients with pNETs treated with everolimus and/or somatostatin analogues, as well as the association between metformin use and PFS time. METHODS: We performed a retrospective analysis of 445 patients with advanced pNET treated at 24 medical centers in Italy from 1999 through 2015. Data on levels of glycemia were collected at time of diagnosis of pNET, before treatment initiation, and during treatment with everolimus (with or without somatostatin analogues), octreotide, or lanreotide. Diabetes was defined as prior or current use of glycemia control medication and/or fasting plasma glucose level ≥ 126 mg/dL, hemoglobin A1c ≥ 6.5% (48 mmol/L), or a random sample of plasma glucose ≥ 200 mg/dL (11.1 mmol/L), with reported classic symptoms of hyperglycemia or hyperglycemic crisis. Patients were assigned to groups based on diagnosis of diabetes before or during antitumor therapy. PFS was compared between patients with vs without diabetes. Among patients with diabetes, the association between metformin use and PFS was assessed. We performed sensitivity and landmark analyses to exclude patients who developed diabetes while receiving cancer treatment and to exclude a potential immortal time bias related to metformin intake. RESULTS: PFS was significantly longer in patients with diabetes (median, 32.0 months) than without diabetes (median, 15.1 months) (hazard ratio for patients with vs without diabetes, 0.63; 95% confidence interval, 0.50-0.80; P = .0002). PFS of patients treated with metformin was significantly longer (median PFS, 44.2 months) than for patients without diabetes (hazard ratio for survival of patients with diabetes receiving metformin vs without diabetes, 0.45; 95% confidence interval, 0.32-0.62; P < .00001) and longer than for patients with diabetes receiving other treatments (median PFS, 20.8 months; hazard ratio, 0.49; 95% confidence interval, 0.34-0.69; P < .0001). In multivariable analysis, adjusted for other factors associated with outcomes, metformin was associated with longer PFS but level of glycemia was not. Metformin was associated with increased PFS of patients receiving somatostatin analogues and in those receiving everolimus, with or without somatostatin analogues. Sensitivity and landmark analyses produced similar results. CONCLUSIONS: In a retrospective study of patients with pNETs, we found a significant association between metformin use and longer PFS.

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

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

Sunitinib in patients with pre-treated pancreatic neuroendocrine tumors: A real-world study.

INTRODUCTION: Besides data reported in a Phase-III trial, data on sunitinib in pancreatic Neuroendocrine Tumors (panNETs) are scanty. AIM: To evaluate sunitinib efficacy and tolerability in panNETs patients treated in a real-world setting. PATIENTS AND METHODS: Retrospective analysis of progressive panNETs treated with sunitinib. Efficacy was assessed by evaluating progression-free survival, overall survival, and disease control (DC) rate (stable disease (SD) + partial response + complete response). Data are reported as median (25th-75th IQR). RESULTS: Eighty patients were included. Overall, 71.1% had NET G2, 26.3% had NET G1, and 2.6% had NET G3 neoplasms. A total of 53 patients (66.3%) had received three or more therapeutic regimens before sunitinib, with 24 patients (30%) having been treated with four previous treatments. Median PFS was 10 months. Similar risk of progression was observed between NET G1 and NET G2 tumors (median PFS 11 months and 8 months, respectively), and between patients who had received ≥ 3 vs ≤ 2 therapeutic approaches before sunitinib (median PFS 9 months and 10 months, respectively). DC rate was 71.3% and SD was the most frequent observed response, occurring in 43 pts (53.8%). Overall, 59 pts (73.8%) experienced AEs, which were grade 1-2 in 43 of them (72.9%), grade 3 in 15 pts (25.4%), and grade 4 in one patient (1.7%). Six pts (7.5%) stopped treatment due to toxicity. CONCLUSIONS: The present real-world experience shows that sunitinib is a safe and effective treatment for panNETs, even in the clinical setting of heavily pre-treated, progressive diseases.

Rationale and protocol of MetNET-2 trial: Lanreotide Autogel plus metformin in advanced gastrointestinal or lung neuroendocrine tumors.

Metformin (MET) has recently emerged as a potentially active agent in cancer prevention and treatment. MET is thought to exert its antitumor effects either via modification of systemic metabolism or through cell-autonomous effects (e.g., activation of AMPK and inhibition of the mTOR pathway). Preliminary findings of the PRIME-NET study suggest that the addition of MET to treatment with everolimus (EVE) and/or somatostatin analogs (SSAs) can provide clinical benefit in diabetic neuroendocrine tumor (NET) patients. In light of this and other retrospective evidence of MET's anticancer activity in NETs, prospective studies are needed. A pilot, single-arm, open-label, prospective study (MetNET-2 trial, NCT02823691) was designed to evaluate the safety of MET in combination with lanreotide in well-differentiated gastrointestinal (WD GI) and lung NETs.

Everolimus treatment for neuroendocrine tumors: latest results and clinical potential.

Neuroendocrine tumors (NETs) are a heterogeneous class of diseases characterized by challenging management. Preclinical evidence shows that the PI3K/AKT/mTOR signaling pathway plays a central role in the pathogenesis and progression of NETs. Everolimus is a direct inhibitor of this pathway, and therefore this molecule appears to be a well-grounded strategy for the treatment of NETs, capable of changing clinical practice. The efficacy and safety of everolimus was demonstrated in the RADIANT trials. In this work, we comment on the results of the RADIANT trials, and other recent key evidence from fully published clinical trials on everolimus, and we discuss the current role of everolimus in the treatment of NETs.

Primary Cerebellar Neuroendocrine Tumors: Chimeras or Real Entities? A Case Report with a 6-Year Follow-Up.

We report the case of a 38-year-old patient who was diagnosed with a cerebellar well-differentiated neuroendocrine tumor (WDNET) in 2009. At first glance, we believed that it was a metastasis from an unrecognized WDNET arising outside the cerebellum. However, despite a prolonged follow-up of 6 years, an extracranial WDNET has never been found. During this time, the tumor recurred locally twice, and the patient was treated with surgery and radiotherapy. At the moment, he enjoys good general conditions and his tumor is under control. Due to the histopathological characteristics and clinical behavior of the tumor, we believe that this is the first report to date of a primary cerebellar WDNET.

Update on medical treatment of small intestinal neuroendocrine tumors.

INTRODUCTION: Small intestinal (SI) neuroendocrine tumors (NETs) are relatively rare tumors. Due to the lack of symptom or specific symptoms, SI-NETs are often diagnosed at an advanced stage, making therapy challenging. The management of patients with advanced stage SI-NETS requires a multidisciplinary approach that combines surgical and medical treatment including novel targeted molecular therapies. AREAS COVERED: This article summarizes current strategies for the medical treatment of SI-NETS. Expert commentary: The treatment plan of advanced-stage SI-NETs should be tailored in a case-by-case manner with the adoption of a multidisciplinary approach that combines different treatment options, including biological targeted therapies. In particular, we believe that the identification of the optimal treatment sequence(s), correct treatment timing and the selection of patients eligible to different treatments need specific investigation in controlled clinical trials.

How do the results of the RADIANT trials impact on the management of NET patients? A systematic review of published studies.

In the last five years, everolimus has demonstrated efficacy in the treatment of neuroendocrine tumors (NETs) of different origins; its efficacy and safety were explored in the RADIANT trials, the last of which (RADIANT-4) has been recently published (December 2015). Overall, evidence collected from the RADIANT studies holds promise to change clinical practice for the treatment of NETs.In this paper, we comment on the role of everolimus within the therapeutic algorithm for NETs treatment, based on the systematic analysis of the RADIANT trials and our experience.

Metformin with everolimus and octreotide in pancreatic neuroendocrine tumor patients with diabetes.

A bidirectional relationship seems to exist between diabetes mellitus and development of pancreatic tumors. Metformin, the most widely used drug in the treatment of Type 2 diabetes mellitus, has recently emerged as a potentially active agent in cancer chemoprevention and treatment. In this article, we discuss the potential correlation between glycemic status, administration of antiglycemic treatments, such as metformin or insulin, and prognosis of pancreatic neuroendocrine tumors patients treated with everolimus and octreotide, on the basis of existing evidence and our experience.