Advanced digestive neuroendocrine tumors: metastatic pattern is an independent factor affecting clinical outcome

Value of Surgical Cytoreduction in Patients with Small Intestinal Neuroendocrine Tumors Metastatic to the Liver and Peritoneum

BACKGROUND

Cytoreductive hepatectomy can improve survival and symptoms of hormonal excess in patients with small intestinal neuroendocrine tumor (siNET) liver metastases, but whether to proceed when peritoneal metastases are encountered at the time of planned cytoreductive hepatectomy is controversial.

METHODS

This was a retrospective review of patients who underwent surgical management of metastatic siNETs at Mayo Clinic between 2000 and 2020. Patients who underwent cytoreductive operation for isolated liver metastases or both liver and peritoneal metastases were compared.

RESULTS

Of 261 patients who underwent cytoreductive operation for siNETs, 211 had isolated liver metastases and 50 had liver and peritoneal metastases. Complete cytoreduction was achieved in 78% of patients with isolated liver metastases and 56% of those with liver and peritoneal metastases (p = 0.002). After complete cytoreduction, median overall survival (OS) was 11.5 years for isolated liver metastases and 11.2 years for liver and peritoneal metastases (p = 0.10), and relief of carcinoid syndrome was ≥ 97% in both groups. After incomplete cytoreduction with debulking of > 90% of hepatic disease and/or closing Lyon score of 1-2, median OS was 6.4 years for isolated liver metastases and 7.1 years for liver and peritoneal metastases (p = 0.12).

CONCLUSIONS

Patients with siNETs metastatic to both the liver and peritoneum have favorable outcomes after aggressive surgical cytoreduction, with the best outcomes observed after complete cytoreduction. Therefore, the presence of peritoneal metastases should not by itself preclude surgical cytoreduction in this population.

[Clinical significance of neuroendocrine tumors : Incidence, symptoms, diagnosis, stage, and prognostic factors and their influence on disease management]

BACKGROUND

Neuroendocrine neoplasms (NEN) are heterogenous with an increasing incidence in recent years.

OBJECTIVES

Overview on incidence, symptoms, diagnostics, grading, imaging and prognostic determinants, including factors having an impact on therapeutic management.

METHODS

Review on current literature, including original articles, reviews, guidelines and expert opinions.

RESULTS

NEN are mainly located in the gastrointestinal tract and their incidence has increased in recent years, mainly due to improved diagnostics, e.g., cross-sectional imaging. Clinical characteristics include hormone excess syndromes (carcinoid syndrome). Laboratory markers such as chromogranin A are commonly used as part of routine diagnostics, followed by endoscopic and endosonographic procedures, which also allow biopsies to be obtained. Tumor spread can be determined by contrast-enhanced computed tomography/magnetic resonance imaging (CT/MRI) or somatostatin receptor (SSRT)-PET/CT (positron emission tomography). Prognostic factors include Ki67 index, type, and grading. Resection with curative intent is the therapy of choice. In a metastasized setting, SSRT-directed treatment approaches are favored, while in dedifferentiated NEN, conventional chemotherapy is needed.

CONCLUSION

A broad diagnostic armamentarium can be offered to NEN patients and the improved diagnostic procedures have most likely caused a raising incidence in recent years. Among others, prognostic factors are Ki67 and NEN subtypes; these clinical determinants also have an impact on patient management.

Correlation between Neurotransmitters (Dopamine, Epinephrine, Norepinephrine, Serotonin), Prognostic Nutritional Index, Glasgow Prognostic Score, Systemic Inflammatory Response Markers, and TNM Staging in a Cohort of Colorectal Neuroendocrine Tumor Patients

Neuroendocrine tumors are uncommon in the gastrointestinal system but can develop in the majority of the body's epithelial organs. Our goal was to examine the presence and clinical application of serum dopamine (DA), serotonin (ST), norepinephrine (NE), and epinephrine (EPI), in addition to determining the significance of the Prognostic Nutritional Index (PNI), Glasgow Prognostic Score (GPS), and systemic inflammatory response (SIR) markers as a prognostic factor for patients with colorectal neuroendocrine tumors (CR-NETs), in various tumor-node-metastasis (TNM) stages. We also wanted to identify the possible connection between them. This study included 25 consecutive patients who were diagnosed with CR-NETs and a control group consisting of 60 patients with newly diagnosed colorectal cancer (CRC). We used the Enzyme-Linked Immunosorbent Assay (ELISA) technique. This study revealed that CR-NET patients showed significantly higher serum levels of DA compared to CRC patients. We showed that serum DA was present in the early stages of CR-NETs, with increasing levels as we advanced through the TNM stages. Moreover, we found a close relationship between the levels of DA and the inflammation and nutritional status of the CR-NET patients in this study. CR-NET patients from the PNI < 47.00 subgroup had a higher level of DA than those from the PNI ≥ 47.00 subgroup. Pearson's correlation analysis revealed correlations between DA, PNI, and the neutrophil/lymphocyte ratio (NLR) and the platelet/lymphocyte ratio (PLR). Both hematological indices were negatively correlated with albumin (ALB). Our investigation's findings relating to the PNI, GPS, SIR, and DA indicate that these tools can be markers of nutritional and systemic inflammatory status, are simple to use, and are repeatable. Further research on this topic could provide valuable insights into which biomarkers to incorporate into clinical practice for the management of CR-NET patients.

When is neoadjuvant chemotherapy indicated in rectal neuroendocrine tumors? An analysis of the National Cancer Database

BACKGROUND

Rectal neuroendocrine tumors (rNET) are rare and challenging to manage. While most patients with small rNET can be definitively treated with local excision, the role of chemotherapy in general and neoadjuvant therapy particularly in managing advanced rNET has not been well established. Therefore, this study aimed to determine which patients with rNET may gain a survival benefit from neoadjuvant chemotherapy.

METHODS

A retrospective cohort analysis of all patients who underwent surgical resection of rNET in the US National Cancer Database (NCDB) (2004-2019) was performed. First, univariate and multivariate Cox regression analyses were performed to determine the independent predictors of poor overall survival (OS) and define the high-risk groups. Afterward, stratified OS analyses were performed for each high-risk group to assess whether neoadjuvant chemotherapy had a survival benefit in each group.

RESULTS

A total of 1837 patients (49.8% female; mean age 56.6 ± 12.3 years) underwent radical resection of a rNET. Tumors > 20 mm in size, clinical T4 tumors, poorly differentiated tumors, and metastatic disease were independent predictors of worse OS and were defined as high-risk groups. Neoadjuvant chemotherapy did not have a significant survival benefit in any of the high-risk groups, except for patients with high-grade rNETs where neoadjuvant therapy significantly improved OS to a mean of 30.9 months compared with 15.9 months when neoadjuvant therapy was not given (p = 0.006).

CONCLUSIONS

Neoadjuvant chemotherapy improved the OS of patients with high-grade rNET by 15 months and may be indicated for this group.

Approaching Small Neuroendocrine Tumors with Radiofrequency Ablation

In recent years, small pancreatic neuroendocrine tumors (pNETs) have shown a dramatic increase in terms of incidence and prevalence, and endoscopic ultrasound (EUS) radiofrequency ablation (RFA) is one potential method to treat the disease in selected patients. As well as the heterogeneity of pNET histology, the studies reported in the literature on EUS-RFA procedures for pNETs are heterogeneous in terms of ablation settings (particularly ablation powers), radiological controls, and radiological indications. The aim of this review is to report the current reported experience in EUS-RFA of small pNETs to help formulate the procedure indications and ablation settings. Another aim is to evaluate the timing and the modality of the radiological surveillance after the ablation. Moreover, new studies on large-scale series are needed in terms of the safety and long-term oncological efficacy of RFA on these small lesions.

The link between menin and pleiotrophin in the tumor biology of pancreatic neuroendocrine neoplasms

MEN1, which encodes menin protein, is the most frequently mutated gene in pancreatic neuroendocrine neoplasms (pNEN). Pleiotrophin (PTN) was reported being a downstream factor of menin and to promote metastasis in different tumor entities. In this study, the effect of menin and its link to PTN were assessed on features of pNEN cells and outcome of pNEN patients. The expression of menin and PTN in pNEN patient tissues were examined by qRT-PCR and western blot and compared to their metastasis status. Functional assays, including transwell migration/invasion and scratch wound healing assays, were performed on specifically designed CRISPR/Cas9-mediated MEN1-knockout (MEN1-KO) pNEN cell lines (BON1^MEN1-KO and QGP1^MEN1-KO ) to study the metastasis of pNEN. Among 30 menin negative pNEN patients, 21 revealed a strong protein expression of PTN. This combination was associated with metastasis and shorter disease-free survival. Accordingly, in BON1^MEN1-KO and QGP1^MEN1-KO cells, PTN protein expression was positively associated with enhanced cell migration and invasion, which could be reversed by PTN silencing. PTN is a predicting factor of metastatic behavior of menin-deficient-pNEN. In vitro, menin is able to both promote and suppress the metastasis of pNEN by regulating PTN expression depending on the tumoral origin of pNEN cells.

Surgery after sunitinib administration to improve survival of patients with advanced pancreatic neuroendocrine neoplasms

BACKGROUND

Little research is available regarding the treatments combining surgical resection with systemic chemotherapy for advanced pancreatic neuroendocrine neoplasm patients. We retrospectively elucidated whether sunitinib administration before surgery in advanced pancreatic neuroendocrine neoplasm (Pan-NEN) patients increases survival.

METHODS

This study included 106 of 326 Pan-NEN patients with distant metastases and/or unresectable locally advanced tumors who visited our department to receive sunitinib for more than 1 mo during April 2002 to December 2019. Risk factors for overall survival (OS) and disease-free survival (DFS) were analyzed.

RESULTS

The median duration of preoperative sunitinib administration and observation time after sunitinib were 6 and 26.5 mo, respectively. Of 106 patients, 31 (29.2%) underwent surgery following sunitinib administration. Hepatectomy, synchronous hepatopancreatectomy, pancreatectomy, and lymphadenectomy were performed for 13, 12, 5, and 1 patient, respectively. The 5-y OS rates in the resected and nonresected groups were 88.9% and 14.1%, respectively (P < .001). In the multivariate analysis, the absence of surgical resection following sunitinib (hazard ratio [HR], 13.1; P = .001), poor differentiation (HR, 5.5; P = .007), and bilateral liver metastases (HR, 3.7; P = .048) were independent risk factors for OS, although large liver tumor volumes were more evident in the nonresected group, as patient characteristics. The median DFS was 16.1 mo in 22 patients who underwent R0/1 resections, and risk factors for postoperative recurrence were Ki-67 index >7.8% (HR, 7.4; P = .02) and R1 resection (HR, 4.4; P = .04).

CONCLUSION

Surgical resection after sunitinib administration improved OS in advanced Pan-NENs.

Octreotide long-acting release (LAR) in combination with other therapies for treatment of neuroendocrine neoplasia: a systematic review

BACKGROUND

In the last decades, the incidence of neuroendocrine neoplasia (NEN) increased from 1 to 5 new diagnoses/100,000 persons/year. The synthetic somatostatin analogues (SSAs) represent the first-choice treatment for both functionally active and inactive gastro-enteric-pancreatic NEN. This systematic review examines the role of octreotide long-acting release (LAR) in combination with other therapies for NEN management.

METHODS

Primary outcomes were the disease control rate and the progression free survival (PFS), defined as the time between treatment initiation and progression of disease. Secondary outcomes were overall survival (OS) and safety.

RESULTS

This systematic review identified 13 studies, concerning the use of octreotide LAR in association with other therapies in advanced NENs and included 1,206 patients. Patients were treated with octreotide LAR in combination with other drugs, mainly with everolimus (404 patients, 35%), but even with Peptide Receptor Radionuclide Therapy, bevacizumab, interferon or fluoride-derivatives. Disease control was observed in 85% cases with SSAs in combination with other therapies; PFS ranged from 15 to 16.4 months and OS from 25 to 61.9 months. SSAs are very well tolerated drugs, with few side effects which are usually mild, not requiring drug withdrawn.

CONCLUSIONS

The review summarizes the effectiveness and available safety data on octreotide LAR in combination with other therapies in patients with NEN and may provide suggestions to address the therapeutic strategy. Further comparative head-to-head studies are needed to understand which is the best combination treatment for patients with progressive NEN after failure of first-line therapy.

[18F]FDG-PET/CT and long-term responses to everolimus in advanced neuroendocrine neoplasia

PURPOSE

This study aims to identify in patients with neuroendocrine neoplasia (NEN) the potential correlation between FDG-PET findings and responses to everolimus therapy to identify predictors of long-term efficacy.

METHODS

Retrospective analysis of patients with sporadic, advanced, progressive NEN treated with everolimus was performed based on the available data on FDG-PET patients obtained before commencing therapy. Data are expressed as the median (25-75th IQR). Risk factor analysis and survival analysis were performed by logistic regression and Cox proportional hazard regression and the determination of Kaplan-Meier curves, as appropriate.

RESULTS

Sixty-six patients were evaluated (NET G1 19.7%, NET G2 75.7%, and NET G3 4.6%), including 45.4% with positive FDG-PET findings. Overall, disease stabilization and a partial response were achieved for 71.2% and 6% of patients, respectively. A long-term response (> 24 months) was observed in 33% of patients. Ki67 was the only predictor of tumor progression (p = 0.03). No significant difference in clinical outcomes was observed between patients with positive or negative FDG-PET findings (median PFS was 24 months and 18 months, respectively, p = 0.337; the disease control rate was 83.3% and 70%, respectively, p = 0.245).

CONCLUSIONS

Everolimus is a valid therapeutic option for advanced, progressive, well-differentiated NEN, even in patients with positive FDG-PET findings.

Bone Metastases in Neuroendocrine Tumors: Molecular Pathogenesis and Implications in Clinical Practice

Skeletal colonization is often regarded as a rare event in patients with neuroendocrine tumors (NETs) although both national registries and retrospective series report an incidence of bone metastases as high as 20% in subjects with advanced disease. While the biological mechanisms leading to bone metastatic colonization in NETs have been poorly investigated so far, key steps of osteotropic mechanisms, including the epithelial-to-mesenchymal transition, preparation of the premetastatic niche, migration of circulating tumor cells towards the bone marrow as well as the resulting alterations of the skeletal metabolism, are likely to operate also during the development of NET bone metastases. The skeleton involvement by NETs has a detrimental impact on both quality of life and patients' prognosis, leading to pain in the majority of symptomatic subjects. While it is currently unclear whether or not the earlier recognition of bone involvement by PET/CT imaging techniques employing 68Ga-DOTA-conjugated peptides might improve outcomes through the exploitation of timely treatments, the management of bone-colonizing NETs is today based only on clinical experience from other osteotropic tumors. Here, we summarize the fundamental molecular mechanisms driving bone colonization and revisit both established and novel treatments for patients with bone metastatic NETs.

Systemic Treatment Selection for Patients with Advanced Pancreatic Neuroendocrine Tumours (PanNETs)

Pancreatic neuroendocrine tumours (PanNETs) are rare diseases and a good example of how research is not only feasible, but also of crucial importance in the scenario of rare tumours. Many clinical trials have been performed over the past two decades expanding therapeutic options for patients with advanced PanNETs. Adequate management relies on optimal selection of treatment, which may be challenging for clinicians due to the fact that multiple options of therapy are currently available. A number of therapies already exist, which are supported by data from phase III studies, including somatostatin analogues and targeted therapies (sunitinib and everolimus). In addition, chemotherapy remains an option, with temozolomide and capecitabine being one of the most popular doublets to use. Peptide receptor radionuclide therapy was successfully implemented in patients with well-differentiated gastro-entero-pancreatic neuroendocrine tumours, but with certain questions waiting to be solved for the management of PanNETs. Finally, the role of immunotherapy is still poorly understood. In this review, the data supporting current systemic treatment options for locally advanced or metastatic PanNETs are summarized. Strategies for treatment selection in patients with PanNETs based on patient, disease, or drug characteristics is provided, as well as a summary of current evidence on prognostic and predictive biomarkers. Future perspectives are discussed, focusing on current and forthcoming challenges and unmet needs of patients with these rare tumours.

Development and Validation of Prognostic Nomograms for Patients with Duodenal Neuroendocrine Neoplasms

Background

This study was designed to predict prognosis of patients with primary duodenal neuroendocrine neoplasms (D-NENs) by developing nomograms.

Material/Methods

Patients diagnosed with D-NENs between 1988 and 2015 were queried from the SEER database and a total of 965 appropriate cases were randomly separated into the training and validation sets. Kaplan-Meier analysis was used to generated survival curves, and the difference among the groups was assessed by the log-rank test. Independent prognostic indicators were acquired by Cox regression analysis, and were used to develop predictive overall survival (OS) and cancer-specific survival (CSS) nomograms. Harrell’s concordance index (C-index), area under the curve (AUC), calibration curves, and decision curve analysis (DCA) were used to assess the efficacy of nomograms. Tumor stage was regarded as a benchmark in predicting prognostic compared with the nomograms built in this study.

Results

The C-index was 0.739 (0.690–0.788) and 0.859 (0.802–0.916) for OS and CSS nomograms, respectively. Calibration curves exhibited obvious consistency between the nomograms and the actual observations. In addition, C-index, AUC, and DCA were better than tumor stage in the evaluative performance of nomograms.

Conclusions

The nomograms were able to predict the 1-, 5-, and 10-year OS and CSS for D-NENs patients. The good performance of these nomograms suggest that they can be used for evaluating the prognosis of patients with D-NENs and can facilitate individualized treatment in clinical practice.

Liver Tumor Burden in Pancreatic Neuroendocrine Tumors: CT Features and Texture Analysis in the Prediction of Tumor Grade and 18F-FDG Uptake

Pancreatic neuroendocrine tumors (p-NETs) are a rare group of neoplasms that often present with liver metastases. Histological characteristics, metabolic behavior, and liver tumor burden (LTB) are important prognostic factors. In this study, the usefulness of texture analysis of liver metastases in evaluating the biological aggressiveness of p-NETs was assessed. Fifty-six patients with liver metastases from p-NET were retrospectively enrolled. Qualitative and quantitative CT features of LTB were evaluated. Histogram-derived parameters of liver metastases were calculated and correlated with the tumor grade (G) and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) standardized uptake value (SUV). Arterial relative enhancement was inversely related with G (−0.37, p = 0.006). Different metastatic spread patterns of LTB were not associated with histological grade. Arterial_entropy was significantly correlated to G (−0.368, p = 0.038) and to Ki67 percentage (−0.421, p = 0.018). The ROC curve for the Arterial_entropy reported an area under the curve (AUC) of 0.736 (95% confidence interval 0.545–0.928, p = 0.035) in the identification of G1–2 tumors. Arterial_uniformity values were correlated to G (0.346, p = 0.005) and Ki67 levels (0.383, p = 0.033). Arterial_entropy values were directly correlated with the SUV (0.449, p = 0.047) which was inversely correlated with Arterial_uniformity (−0.499, p = 0.025). Skewness and kurtosis reported no significant correlations. In conclusion, histogram-derived parameters may predict adverse histological features and metabolic behavior of p-NET liver metastases.

Histopathological Revision for Gastroenteropancreatic Neuroendocrine Neoplasms in Expert Centers: Does It Make the Difference?

BACKGROUND

The correct histopathological diagnosis of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) is crucial for treatment selection and prognostication. It is also very challenging due to limited experience in nonexpert centers. Revision of pathology is standard of care for most patients who are referred to NEN expert centers.

OBJECTIVES

To describe the clinical impact of histopathological revision for GEP-NEN patients referred to an expert center.

METHODS

Retrospective multicenter analysis of all GEP-NENs receiving a histopathological revision in 6 European NEN expert centers (January 2016 to December 2016) to evaluate the impact on patient management.

RESULTS

175 patients were included and 14.7% referred for a second opinion. Histological samples were 69.1% biopsies, 23.4% surgical specimens, and 7.5% endoscopic resections. Histopathological changes due to revision included first assessment of Ki67 in 8.6% of cases, change in grading in 11.4% (3.4% G1 to G2; 5.7% G2 to G1; 0.6% G2 to G3; 1.7% G3 to G2), definition of tumor invasion in 10.8%, additional immunohistochemical staining in 2.3%, diagnosis of mixed adenoneuroendocrine carcinoma in 3.4%, exclusion of NEN in 3.4%, first diagnosis of NEN in 2.3%, and tumor differentiation for G3 in 1.7%. The revision had a clinical impact in 36.0% of patients, leading to a new therapeutic indication in 26.3%. The indication to then perform a new imaging test occurred in 21.1% and recommendation to follow-up with no further treatment in 6.3%.

CONCLUSIONS

Histopathological revision in expert centers for NENs can change the diagnosis, with a significant clinical impact in about one third of patients.

Impact of Peritoneal Metastasis on Survival of Patients With Small Intestinal Neuroendocrine Tumor

The liver and peritoneum are the 2 most common distant metastatic sites for small intestinal neuroendocrine tumors (SI-NET). In this study, we evaluated the differential impact of hepatic and/or peritoneal metastasis on prognosis of SI-NET patients. Surgical Pathology archives were searched for SI-NET resections performed between January 1, 1994 and August 31, 2017. Two hundred nineteen cases with clinical follow-up data were identified. Pathology reports and electronic medical records were reviewed. The 219 patients included 104 females and 115 males with a median age of 59 years (range, 19 to 85 y). There were 71 (33%) cases without hepatic or peritoneal metastasis, 80 (37%) with hepatic metastasis only, 14 (6%) with peritoneal metastasis only, and 53 (24%) with both hepatic and peritoneal metastasis at the time of surgery or during follow-up. The number of primary tumors, largest tumor size, lymph node metastasis, pT category, and sex were not significant independent prognostic factors in multivariate Cox proportional hazard regression. Age was the only variable other than presence of metastatic disease that was associated with worse prognosis (5% increase in risk/year of age; 95% confidence interval, 1.7%-8.2%; P=0.003). After controlling for patient age, pairwise comparisons of marginal linear predictions showed increased risk with peritoneal metastasis, with or without associated hepatic metastasis, compared to hepatic metastasis only. In conclusion, although limited by the number of patients with peritoneal metastasis only, these results support substratifying patients with metastatic SI-NET by anatomic site of metastasis.

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.

Consideration of Age Is Necessary for Increasing the Accuracy of the AJCC TNM Staging System of Pancreatic Neuroendocrine Tumors

Purpose: Currently, of the two most common staging systems of pancreatic neuroendocrine tumors (pNETs) one is from the European Neuroendocrine Tumor Society (ENETS) and the other is from the American Joint Committee on Cancer (AJCC). However, there are imperfections in both these staging systems. Patients and methods: Patients were selected retrospectively from the Surveillance Epidemiology and End Results (SEER) database (2004 to 2013). The effect of age on the hazard ratio (HR) was evaluated using restricted cubic splines. The discriminatory power of the staging systems was determined using the concordance index (C-index). Results: A total of 3,034 patients with pNETs were included in the final analyses. The risk of death increased slowly along with age for patients under 60 years of age, but the risk of death rose sharply for those over 60 years of age, forming a mirrored L-shaped survival curve. In the current AJCC tumor-node-metastasis (TNM) staging system, no statistical significance was observed between stages IA and IB (p = 0.105). Patients with stage IIB even had longer OS than patients with IIA, although there was no statistical significance (p = 0.574). The proportion of stage III patients was small (2.7%). In the proposed aTNM staging system, significant survival differences could be observed among stage I, IIA, and IIB (p < 0.001) and the proportion of stage III rose from 2.7 to 25.7%. Conclusion: Our findings suggest that age has a critical influence on the survival of patients with pNETs. Age should be considered as a factor in future staging systems of pNETs.

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.

Association of preoperative monocyte-to-lymphocyte and neutrophil-to-lymphocyte ratio with recurrence-free and overall survival after resection of pancreatic neuroendocrine tumors (US-NETSG)

BACKGROUND

Preoperative systemic inflammatory response plays a crucial role in tumorigenesis, progression, and prognosis; and neutrophil, monocyte, and lymphocyte counts serve as important biomarkers. An altered monocyte-to-lymphocyte ratio (MLR) and neutrophil-to-lymphocyte ratio (NLR) has been reported to be associated with a favorable prognosis for certain hematologic malignancies and breast cancer. The aim of this study was to investigate the prognostic significance of MLR, NLR in patients with resectable PNETs.

METHODS

Patients undergoing surgery for PNETs between 2000 and 2016 were identified using a large, multi-center database. NLR and MLR were calculated and Contal and O'Quigley analysis was used to determine the optimal cutoff value.

RESULTS

A total of 620 patients were included in the analytic cohort. The prognostic implications of blood count parameters were evaluated in both univariate and multivariate analysis. The univariate analysis revealed that low MLR and NLR is associated with significantly improved overall survival (OS; P < .01) and recurrence-free survival (RFS; P < .01). On multivariate analysis, in addition to tumor size and grade, NLR was an independent predictor of improved OS and RFS.

CONCLUSION

In addition to established tumor-specific factors, preoperative NLR levels can serve as a valuable biomarker that can be used as a predictor of OS and RFS after resection of PNETs.

Role of Combined [68Ga]Ga-DOTA-SST Analogues and [18F]FDG PET/CT in the Management of GEP-NENs: A Systematic Review

Gastro-entero-pancreatic neuroendocrine neoplasia (GEP-NENs) are rare tumors, but their frequency is increasing. Neuroendocrine tumors normally express somatostatin (SST) receptors (SSTR) on cell surface, especially G1 and G2 stage tumors, but they can show a dedifferentiation in their clinical history as they become more aggressive. Somatostatin receptor imaging has previously been performed with a gamma camera using [111In]In or [99mTc]Tc-labelled compounds, while [68Ga]Ga-labelled compounds and PET/CT imaging has recently become the gold standard for the diagnosis and management of these tumors. Moreover, in the last few years 18F-fluorodeoxyglucose ([18F]FDG) PET/CT has emerged as an important tool to define tumor aggressiveness and give relevant prognostic information, particularly when coupled with [68Ga]Ga-labelled SST analogues PET/CT. This review focuses on the importance of combined imaging with [68Ga]Ga-labelled SST analogues and [18F]FDG for the management of GEP-NENs.

Multidisciplinary Management of Neuroendocrine Neoplasia: A Real-World Experience from a Referral Center

PURPOSE

Multidisciplinary approach is widely advised for an effective care of patients with neuroendocrine neoplasia (NEN). Since data on efficacy of multidisciplinary management of NENs patients in referral centers are scanty, this study aimed at analyzing the modality of presentation and clinical outcome of patients with NENs managed by a dedicated multidisciplinary team.

METHODS

In this prospective observational study, we included all consecutive new patients visiting the Sant'Andrea Hospital in Rome (ENETS-Center of Excellence) between January 2014 and June 2018.

RESULTS

A total of 195 patients were evaluated. The most frequent sites were pancreas (38.5%), small bowel (22%), and lung (9.7%). Median Ki67 was 3%. After the first visit at the center, additional radiological and/or nuclear medicine procedures were requested in 163 patients (83.6%), whereas histological data revision was advised in 84 patients (43.1%) (revision of histological slides: 27.7%, new bioptic sampling: 15.4%). After that, disease imaging staging and grading was modified in 30.7% and 17.9% of patients, respectively. Overall, a change in therapeutic management was proposed in 98 patients (50.3%).

CONCLUSIONS

Multidisciplinary approach in a dedicated team may lead to change of disease imaging staging and grading in a significant proportion of patients. Enhancing referral routes to dedicated-NEN center should be promoted, since it may improve patients' clinical outcome.

Survival and prognostic factors analysis of 151 intestinal and pancreatic neuroendocrine tumors: a single center experience

Background

Intestinal and pancreatic neuroendocrine tumors (IP-NETs) are rare tumors with heterogeneous outcomes. The aim of our study was to determine the clinical, therapeutic and pathological factors which impact the overall survival (OS) in IP-NETs.

Methods

All the patients diagnosed with IP-NETs at the Nantes University Hospital between October 1994 and October 2013 were retrospectively analysed. Patients with MEN-1 (Type 1 Multiple Endocrine Neoplasia) or Von Hippel-Lindau syndrome were excluded. Additionally, a prospective analysis of tumor grade (mitotic index and Ki67 index) was performed on tumor samples. OS was evaluated by Kaplan-Meier method and prognostic factors by log-rank test and Cox model.

Results

The study included 151 patients. Median age was 60 (range, 14-81). Primary tumor was pancreatic in 86 patients (56.95%) and intestinal in 65 patients (43.05%). Tumors were metastatic (synchronous or metachronous) in 72 patients (47.7%). The median OS was 157 months. For all IP-NETs, age >65 years (P<0.0001), Ki67 >5% (P=0.03), synchronous metastases (P=0.016), primary tumor size >25 mm (P=0.03) and emergency surgery (P=0.007) were independent poor prognostic factors.

Conclusions

In this large series of patients with IP-NET, age >65 years, Ki67 >5%, primary tumor size >25 mm, synchronous metastases and emergency surgery for acute complications have been identified as independent poor prognostic factors.

Accuracy of grading pancreatic neuroendocrine neoplasms with Ki-67 index in fine-needle aspiration cellblock material

OBJECTIVE

The aim of this study was to assess the preoperative tumour grade of pancreatic neuroendocrine neoplasms (panNENs) by determining the Ki-67 index in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) material and to correlate the preoperative tumour grade with the postoperative tumour grade in surgical specimens.

METHODS

We performed a retrospective review of the institutional pathology database over a 10-year period (2007-2017) to identify all cases of panNENs with corresponding preoperative EUS-FNA cytological material and surgical specimens. Fifteen cases with adequate EUS-FNA material (more than 400 tumour cells on cellblock) were identified. The cytological and histological samples were graded based on the mitotic rate and the Ki-67 index in accordance with the 2017 World Health Organisation grading system for panNENs. The tumour grades determined on EUS-FNA cellblock material were compared with the histological tumour grades.

RESULTS

Mean age at diagnosis was 64.8 ± 12.7 years (range, 38-85 years). The grading scores assigned to the cytological and histological samples were concordant in all 15 (100%) cases. Of those, two (13%) cases were scored as grade 1, nine (60%) cases as grade 2 and four (27%) cases as grade 3 tumours.

CONCLUSION

Our study shows that tumour grade in patients with PanNENs can be reliably determined by assessing the Ki-67 index in EUS-FNA specimens based on the 2017 World Health Organisation classification and grading system.

Grade 2 pancreatic neuroendocrine tumors: overbroad scope of Ki-67 index according to MRI features

PURPOSE

To evaluate the value of MR imaging features in stratifying Grade 2 (G2) pancreatic neuroendocrine tumors (PNETs) using the 5% cut-off value of the Ki-67 index as reference standards.

MATERIALS AND METHODS

Between January 2010 and October 2016, 41 G2 PNET patients (One patient had 3 tumors) with preoperative MR imaging were included. Tumor grading was based on the revised 2016 World Health Organization classification of PNETs. MR imaging features included size, shape, consistency, T1-w and T2-w signal intensities, enhancement pattern, apparent diffusion coefficient (ADC) ratios (tumor/normal pancreatic parenchyma).

RESULTS

16 Ki-67 index < 5% tumors (SKIT, 37.2%) and 27 Ki-67 index ≥ 5% tumors (LKIT, 62.8%) of G2 were evaluated. The LKIT showed solid consistency (85% vs. 50%, P < 0.05), incomplete envelope-like reinforcement in a delayed phase (74% vs. 62%, P < 0.05), and liver or lymph node metastases (67% vs. 31%, P < 0.05) more frequently than did SKIT. However, ADC ratios of LKIT were smaller than SKIT (0.85 ± 0.23 vs. 1.29 ± 0.39, P = 0.001). Using binary logistic regression analysis, the ADC ratio was an independent significant differentiator of SKIT from LKIT. The AUROC of ADC ratios was 0.816 ± 0.07. The optimal cut-off value for the identification of LKIT was 1.25 × 10^-3 (sensitivity 96.3%, specificity 62.5%).

CONCLUSION

MRI features may identify the overbroad scope of G2 PNETs and help predict Ki-67 values, as a surrogate for tumor aggressiveness, in G2 PNETs. An optimal cut-off value for predicting Ki-67 status (≥/< 5%) was 1.25 × 10^-3 of ADC ratio.

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.

Markers of Systemic Inflammatory Response are Prognostic Factors in Patients with Pancreatic Neuroendocrine Tumors (PNETs): A Prospective Analysis

BACKGROUND

The prognosis and behavior of pancreatic neuroendocrine tumors (PNETs) vary and may be divergent even at the same stage or tumor grade. Markers of systemic inflammatory response are readily available and are inexpensive, and have been shown to be prognostic factors in several cancers.

OBJECTIVE

The aim of this study was to evaluate the prognostic utility of markers of systemic inflammatory response in patients with PNETs.

METHODS

A prospective study of 97 patients with PNETs was performed (median follow-up of 15 months, range 12-73 months). Neutrophil-to-lymphocyte ratios (NLRs) and lymphocyte-to-monocyte ratios (LMRs) were calculated at baseline and preoperatively. The primary outcome measures were progression-free survival (PFS) and recurrence-free survival (RFS) after curative resection.

RESULTS

Among all patients, an NLR > 2.3 [hazard ratio (HR) 2.53, 95% confidence interval (CI) 1.05-6.08, p = 0.038] and the presence of distant metastases (HR 2.8, 95% CI 1.26-6.21, p = 0.012) were independent predictors of disease progression. Among patients who did not undergo surgery during the study period, both platelet-to-lymphocyte ratio (PLR) > 160.9 (HR 5.86, 95% CI 1.27-27.08, p = 0.023) and mean platelet volume > 10.75 fL (HR 6.63, 95% CI 1.6-27.48, p = 0.009) were independently associated with worse PFS on multivariable analysis. Among patients who underwent complete resection, an LMR < 3.46 was associated with a worse RFS (HR 9.72, 95% CI 1.19-79.42, p = 0.034).

CONCLUSIONS

PLR > 160.9 and an MPV > 10.75 fL at baseline are independent predictors of disease progression, while an LMR < 3.46 is an independent predictor of tumor recurrence after complete resection in patients with PNETs.

Antiproliferative effect of somatostatin analogs in advanced gastro-entero-pancreatic neuroendocrine tumors: a systematic review and meta-analysis

A meta-analysis has systematically investigated the antineoplastic efficacy and safety of somatostatin analogs (SSAs) in advanced gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs). Randomized controlled trials (RCTs) reporting the hazard ratio (HR) for disease progression (DP) were evaluated. Response rate and risk ratio (RR) for adverse events were also analyzed. A total of 289 patients (143 receiving SSAs vs. 146 placebo) were evaluated from two RCTs. A significant benefit from SSAs in terms of disease control was observed (HR 0.41, 95% CI: 0.29 to 0.58, P < 0.01; I20%), response rate being 58.0% vs. 32.2%, respectively.The occurrence of adverse events significantly differed from the placebo arm only in terms of biliary stones (RR 3.79, 95% CI: 1.28 to 11.17, P = 0.02; I20%). In conclusion, SSAs showed an antiproliferative effect in advanced GEP-NETs, with a good safety profile.

Functional Imaging in the Follow-Up of Enteropancreatic Neuroendocrine Tumors: Clinical Usefulness and Indications

CONTEXT

Functional imaging tests (FITs) detecting somatostatin receptor expression [i.e., somatostatin receptor scintigraphy, 68Ga-DOTA positron emission tomography/computed tomography (CT)] have a pivotal role in the diagnosis of neuroendocrine tumors (NETs), although their indication during follow-up still needs to be clarified.

OBJECTIVE

Investigate the role of FITs after diagnosis of metastatic enteropancreatic NETs, identifying patients who might benefit from these exams.

DESIGN

Multicenter retrospective analysis of metastatic enteropancreatic NETs.

SETTING

Analysis of imaging tests performed between January 1995 and December 2015 in Rome, Berlin, Milan, Marburg, or Graz.

SUBJECTS

One hundred forty-three patients with metastatic pancreatic NETs and small intestine NETs, at least 2-year follow-up, and positive FITs.

INTERVENTIONS

Patients had received CT every 6 months (unless clinical conditions and tumor behavior required shorter intervals) and FIT every 12 months.

MAIN OUTCOME MEASURES

Clinical usefulness of FITs, defined as changes in patient management (indication to biopsy, medical therapy, surgery, or further imaging tests) due only to FITs.

RESULTS

FITs affected management in 73.4% of patients, mostly when G2 vs G1 [odds ratio (OR), 2.40; 95% confidence interval (CI), 1.09 to 5.27; P = 0.03]. Changes were observed in a 12-month time frame especially with pancreatic NETs vs small intestine NETs (OR, 2.89; 95% CI, 1.09 - 7.67; P = 0.03) or metastases since diagnosis vs developed during follow-up (OR, 4.00; 95% CI, 1.43 to 11.17; P < 0.01).

CONCLUSIONS

FITs used in addition to CT in the follow-up of stage IV enteropancreatic NETs improve patient management (especially for G2 tumors). Follow-up program should be tailored according to tumor features.

Stage IV Gastro-Entero-Pancreatic Neuroendocrine Neoplasms: A Risk Score to Predict Clinical Outcome

Background

Several risk factors predict clinical outcome in gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs); however, the impact of their combination has not been investigated so far.

Patients and Methods

A retrospective analysis of stage IV GEP-NENs was performed. Multivariate analysis for progression of disease (PD) was performed by Cox proportional hazards method to obtain a risk score. Area under the curve obtained by receiver operating characteristic analysis was used to assess the score performance. Progression-free survival analysis was performed by Kaplan-Meier method.

Results

Two hundred eighty-three stage IV GEP-NENs were evaluated, including 93 grade 1 neuroendocrine tumors (32.9%), 153 grade 2 neuroendocrine tumors (54%), and 37 grade 3 neuroendocrine carcinomas (13.1%). Independent risk factors for PD were Ki67, proportion of metastatic liver involvement, and presence of extra-abdominal metastases. The risk score was calculated as follows: (0.025 × Ki67) + [(0 if no liver metastases or liver involvement &lt;25%) OR (0.405 if liver involvement 25%–50%) OR (0.462 if liver involvement &gt;50%)] + [(0 if no extra-abdominal metastases) OR (0.528 if extra-abdominal metastases present)]. The risk score accuracy to predict PD was superior compared with the G grading system (area under the curve: 0.705 and 0.622, respectively). Three subgroups of patients with low, intermediate, and high risk of PD according to risk score were identified, median progression-free survival being 26 months, 19 months, and 12 months, respectively.

Conclusion

In stage IV GEP-NENs, a risk score able to predict PD was obtained by combining Ki67, proportion of metastatic liver involvement, and presence of extra-abdominal metastases. The score may help to discriminate patients with different progression risk level to plan tailored therapeutic approaches and follow-up programs.

Stage IV Gastro-Entero-Pancreatic Neuroendocrine Neoplasms: A Risk Score to Predict Clinical Outcome

BACKGROUND

Several risk factors predict clinical outcome in gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs); however, the impact of their combination has not been investigated so far.

PATIENTS AND METHODS

A retrospective analysis of stage IV GEP-NENs was performed. Multivariate analysis for progression of disease (PD) was performed by Cox proportional hazards method to obtain a risk score. Area under the curve obtained by receiver operating characteristic analysis was used to assess the score performance. Progression-free survival analysis was performed by Kaplan-Meier method.

RESULTS

Two hundred eighty-three stage IV GEP-NENs were evaluated, including 93 grade 1 neuroendocrine tumors (32.9%), 153 grade 2 neuroendocrine tumors (54%), and 37 grade 3 neuroendocrine carcinomas (13.1%). Independent risk factors for PD were Ki67, proportion of metastatic liver involvement, and presence of extra-abdominal metastases. The risk score was calculated as follows: (0.025 × Ki67) + [(0 if no liver metastases or liver involvement <25%) OR (0.405 if liver involvement 25%-50%) OR (0.462 if liver involvement >50%)] + [(0 if no extra-abdominal metastases) OR (0.528 if extra-abdominal metastases present)]. The risk score accuracy to predict PD was superior compared with the G grading system (area under the curve: 0.705 and 0.622, respectively). Three subgroups of patients with low, intermediate, and high risk of PD according to risk score were identified, median progression-free survival being 26 months, 19 months, and 12 months, respectively.

CONCLUSION

In stage IV GEP-NENs, a risk score able to predict PD was obtained by combining Ki67, proportion of metastatic liver involvement, and presence of extra-abdominal metastases. The score may help to discriminate patients with different progression risk level to plan tailored therapeutic approaches and follow-up programs. The Oncologist 2017;22:409-415Implications for Practice: Clinical outcome of patients with advanced gastro-entero-pancreatic neuroendocrine neoplasms is affected by several risk factors, including the proliferative index Ki67, extension of liver metastases, and the presence of distant extra-abdominal lesions. A risk score that combines these variables may help physicians dealing with these diseases to plan the optimal therapeutic approach and follow-up program.

Digestive neuroendocrine neoplasms: A 2016 overview

Digestive neuroendocrine neoplasms (DNENs) have an incidence of 2.39 per 100,000 inhabitants per year, and a prevalence of 35 cases per 100,000; the gap between these rates is to be referred to the relatively long survival that characterizes the majority of these tumors, which can be thus considered as chronic oncological diseases. Up to 80% of patients are stage IV since the first diagnosis, presenting a 5-yr overall survival rate of 35%-55% and a twice higher mortality than limited disease. DNENs express somatostatin receptors in more than 80% of cases, detected through immunohistochemistry or functional imaging tests (FITs). This feature identifies patients who may benefit from "cold" somatostatin analogs (SSAs) or peptide receptors radionuclide therapy, although SSAs are sometimes used also with a negative uptake at FITs. The therapeutic options have been recently increased after the identification of molecular pathways involved in DNENs pathogenesis, and the subsequent use of targeted therapies (i.e., Everolimus and Sunitinib) for these neoplasms. This review offers an overview about pancreatic and small bowel NENs, critically underlining the issues that still need to be clarified and the future perspectives to be investigated.

Neuroendocrine liver metastases: Value of apparent diffusion coefficient and enhancement ratios for characterization of histopathologic grade

PURPOSE

To assess the value of apparent diffusion coefficient (ADC) measured with diffusion-weighted imaging (DWI) and enhancement ratios (ER) measured with contrast-enhanced T1-weighted imaging (CE-T1WI) for the characterization of histopathologic tumor grade of neuroendocrine tumor liver metastases (NETLM).

MATERIALS AND METHODS

Twenty-two patients with pathology-proven NETLM and pretreatment 1.5 Tesla (T) and 3T MRI including DWI were included in this Institutional Review Board-approved retrospective study. ADC histogram parameters, including mean, minimum (min), skewness, and kurtosis as well as ER, were computed for all lesions. Tumor grading was based on the World Health Organization 2010 classification. Kruskal-Wallis and Mann-Whitney test were used to assess for differences in ADC and ER between different tumor grades. MRI parameters were correlated with pathologic findings using Spearman correlation test. Receiver operating characteristic analysis was performed to determine optimum thresholds for predicting tumor grade.

RESULTS

Forty-eight NETLM (mean size 3.5 cm) were analyzed with the following grade distribution: G1 (n = 25), G2 (n = 16), and G3 (n = 7). ADC-mean (×10^-3 mm² /s) of G3 tumors (0.87 ± 0.43) was significantly lower than that of G1 (1.47 ± 0.63) and G2 (1.27 ± 0.63; P = 0.042). A weak significant negative correlation was observed between ADC and tumor grade (ADC-mean: r = -0.33, P = 0.02; ADC-min: r = -0.37, P = 0.01) and Ki-67 (ADC-mean: r = -0.31, P = 0.03; ADC-min: r = -0.39, P = 0.007). AUROC, sensitivity and specificity of ADC-mean/ADC-min/ER (measured at the early arterial phase) for differentiation of G3 versus G1-G2 were 0.80/0.76/0.67, 100%/50%/70%, and 68.4%/84.2%/66.6%, respectively.

CONCLUSION

ADC is a promising marker for characterization of histopathologic grade of NETLM. These results should be confirmed in a prospective study. J. Magn. Reson. Imaging 2016;44:1432-1441.

Histopathology of NET: Current concepts and new developments

The diagnosis of neuroendocrine tumors is based on their histopathologic appearance and immunohistochemical profile. With the WHO 2010 classification formal staging and grading was introduced for gastro-entero-pancreatic NET, however, the nomenclature for lung neuroendocrine tumors still relies on the carcinoid term. In this review we also focus on the situation of neuroendocrine carcinoma of unknown primary, tissue biomarkers and actual controversies in the histopathology of NEN.

Long-term outcomes and prognostic factors in 78 Japanese patients with advanced pancreatic neuroendocrine neoplasms: a single-center retrospective study

OBJECTIVE

Despite an increase in the number of Japanese patients with pancreatic neuroendocrine neoplasms, long-term outcomes and prognostic factors, especially for those with advanced disease, remain unclear.

METHODS

We retrospectively reviewed the medical records of 78 patients with unresectable pancreatic neuroendocrine neoplasms treated at our hospital from January 1987 to March 2015. Survival analyses were performed using Kaplan-Meier methods. Prognostic significance of several clinicopathological factors were analyzed by univariate and multivariate analyses using a Cox regression model.

RESULTS

Median overall survivals of pancreatic neuroendocrine tumor (n = 64) and pancreatic neuroendocrine carcinoma (n = 14) were 83.7 and 9.1 months, respectively (hazard ratio: 0.02, 95% confidence interval: 0.01-0.08, P < 0.001). Although no significant differences were observed using a Ki-67 cut-off value of 2% (hazard ratio: 0.46, 95% confidence interval: 0.16-1.13, P = 0.0989), a Ki-67 cut-off of 10% was a significant predictor in patients with pancreatic neuroendocrine tumor (hazard ratio: 9.95, 95% confidence interval, 3.01-32.97, P < 0.001). Treatment after the advent of targeted therapy (hazard ratio: 0.07, 95% confidence interval: 0.03-0.19, P < 0.001) and the presence of bone metastases (hazard ratio: 4.38, 95% confidence interval: 1.42-11.29, P = 0.013) were significant prognostic factors in patients with pancreatic neuroendocrine tumor evaluated by univariate analysis. Multivariate analysis also revealed that a Ki-67 index ≥10% (hazard ratio: 38.8, 95% confidence interval: 8.42-226.62, P < 0.001), approval of targeted therapy (hazard ratio: 0.02, 95% confidence interval: 0.00-0.11, P < 0.001) and bone metastases (hazard ratio: 5.56, 95% confidence interval: 1.10-24.00, P = 0.039) were independent prognostic factors.

CONCLUSIONS

We elucidated the long-term outcomes and prognostic factors in Japanese patients with advanced pancreatic neuroendocrine neoplasms.

Small intestinal neuroendocrine tumors with liver metastases and resection of the primary: Prognostic factors for decision making

INTRODUCTION

Patients with small intestine neuroendocrine tumors present with liver metastases in 50-75% of cases at diagnosis. The aim of the present study was to assess prognostic factors in patients with liver metastases from intestinal neuroendocrine tumor after primary tumor surgical removal with or without liver surgery or radiofrequency ablation. The primary endpoint was disease-specific survival.

METHODS

Data regarding seventy-eight consecutive patients with liver metastases who undergone primary tumor surgical removal between 1996 and 2011 were extracted from the institutional tumor registry and retrospectively analyzed.

RESULTS

Liver tumor burden was <25% in 43 (55.1%) 25-50% in 30 (38.5%) and >50% in 5 (6.4%) patients. For the whole cohort of patients disease-specific survival at 3, 5 and 8 years was 93.2%, 83.6% and 77.3%, respectively. Fifteen patients who underwent radical liver surgery were all alive with a median survival of 106 months (range 18-152 months). In multivariate analysis the Ki-67 index in a continuous fashion significantly correlate with prognosis (p = 0.021). Liver tumor burden (p = 0.036) and extrahepatic involvement (p = 0.03), were the most powerful prognosticators for patients who underwent only debulking surgery.

CONCLUSION

The Ki-67 index, the liver tumor burden and the presence of extrahepatic metastases should be carefully considered in the selection criteria for liver debulking in asymptomatic patients.

Long-Term Outcomes of Surgical Management of Pancreatic Neuroendocrine Tumors with Synchronous Liver Metastases

BACKGROUND

The value of surgical resection in the management of pancreatic neuroendocrine tumors (PNET) with liver metastases (LM) is still debated. The aim of this study was to evaluate the outcomes of surgery of PNET with LM.

METHODS

Patients with PNET with synchronous LM between 2000 and 2011 from 4 high-volume institutions were included. The patients were divided into 3 groups: curative resection, palliative resection, and no resection.

RESULTS

Overall, 166 patients were included. Eighteen patients (11%) underwent curative resection, 73 patients (43%) underwent palliative resection, and 75 patients (46%) underwent conservative treatment. The median overall survival (OS) from the time of diagnosis was 73 months. Patients who underwent curative resection had a significantly better median OS from the initial diagnosis compared with those who underwent palliative resection and those who were conservatively treated (97 vs. 89 vs. 36 months, p = 0.0001). The median OS from the time of diagnosis in those patients who underwent radical or palliative resection was 97 months, with a 5-year survival rate of 76%. On multivariate analysis, factors associated with OS from the time of diagnosis were the presence of bilobar metastases, tumor grading, and curative resection in a first model. On a second model, curative or palliative surgery was an independent predictor of OS. Among 91 patients who underwent surgery, the presence of pancreatic neuroendocrine carcinoma G3 was the only factor independently associated with a poorer survival after surgery (median OS: 35 vs. 97 months, p < 0.0001).

CONCLUSIONS

Patients with LM from PNET benefit from surgical resection, although surgery should be reserved to well- or moderately differentiated forms.

Neuroendocrine neoplasms of the pancreas at dynamic enhanced CT: comparison between grade 3 neuroendocrine carcinoma and grade 1/2 neuroendocrine tumour

OBJECTIVES

To identify the CT features in differentiating grade 3 neuroendocrine carcinomas from grade 1/2 neuroendocrine tumours.

METHODS

This study included 161 patients with surgically confirmed pancreatic neuroendocrine neoplasms. Pathology slides were reviewed to determine the tumour grade. CT image analysis included size, pattern, calcification, margin, pancreatic duct dilatation, bile duct dilatation, vascular invasion, arterial enhancement ratio, and portal enhancement ratio. We used 2 cm, 3 cm, and 4 cm as cutoff values of tumour size and 0.9 and 1.1 of enhancement ratio to determine the sensitivity and specificity.

RESULTS

Pathology analysis identified 167 lesions in 161 patients. 154 lesions (92 %) were grade 1/2 and 13 (8 %) were grade 3. Portal enhancement ratio (< 1.1) showed high sensitivity and specificity 92.3 % and 80.5 %, respectively in differentiating grade 3 from grade 1/2. It showed the highest odds ratio (49.60), followed by poorly defined margin, size (> 3 cm), bile duct dilatation, and vascular invasion. When at least two of these five criteria were used in combination, the sensitivity and specificity for diagnosing grade 3 were 92.3 % (12/13) and 87.7 % (135/154), respectively.

CONCLUSIONS

By using specific CT findings, grade 3 can be differentiated from grade 1/2 with a high diagnostic accuracy leading to an appropriate imaging staging.

KEY POINTS

• Neuroendocrine carcinomas should be differentiated from neuroendocrine tumours. • Neuroendocrine carcinomas can be differentiated from neuroendocrine tumours on dynamic CT. • Neuroendocrine carcinomas show iso- or hypo-enhancement on portal venous phase CT.

Current status of Interventional Radiology in the management of Gastro-Entero-Pancreatic Neuroendocrine Tumours (GEP-NETs)

Within the group of Gastro-Entero-Pancreatic Neuroendocrine tumours (GEP-NETs), several heterogeneous malignancies are included with a variety of clinical manifestations and imaging characteristics. Often these cases are inoperable and minimal invasive treatment offered by image-guided procedures appears to be the only option. Interventional radiology offers a valid solution in the management of primary and metastatic GEP-NETs. The purpose of this review article is to describe the current status of the role of Interventional Radiology in the management of GEP-NETs.

Real-world study of everolimus in advanced progressive neuroendocrine tumors

Everolimus is a valid therapeutic option for neuroendocrine tumors (NETs); however, data in a real-world setting outside regulatory trials are sparse. The aim of this study was to determine everolimus tolerability and efficacy, in relation to previous treatments, in a compassionate use program. A total of 169 patients with advanced progressive NETs treated with everolimus were enrolled, including 85 with pancreatic NETs (pNETs) and 84 with nonpancreatic NETs (non-pNETs). Previous treatments included somatostatin analogs (92.9%), peptide receptor radionuclide therapy (PRRT; 50.3%), chemotherapy (49.7%), and PRRT and chemotherapy (22.8%). Overall, 85.2% of patients experienced adverse events (AEs), which were severe (grade 3-4) in 46.1%. The most frequent severe AEs were pneumonitis (8.3%), thrombocytopenia (7.7%), anemia (5.3%), and renal failure (3.5%). In patients previously treated with PRRT and chemotherapy, a 12-fold increased risk for severe toxicity was observed, with grade 3-4 AEs reported in 86.8% (vs. 34.3% in other patients). In addition, 63.3% of patients required temporarily everolimus discontinuation due to toxicity. Overall, 27.8% of patients died during a median follow-up of 12 months. Median progression-free survival (PFS) and overall survival (OS) were 12 months and 32 months, respectively. Similar disease control rates, PFS, and OS were reported in pNETs and non-pNETs. In the real-world setting, everolimus is safe and effective for the treatment of NETs of different origins. Higher severe toxicity occurred in patients previously treated with systemic chemotherapy and PRRT. This finding prompts caution when using this drug in pretreated patients and raises the issue of planning for everolimus before PRRT and chemotherapy in the therapeutic algorithm for advanced NETs.