Sunitinib shrinks NET-G3 pancreatic neuroendocrine neoplasms

Characterization and optimization of magnetic molecularly imprinted nanofibers for determination of sunitinib in human serum and capsule samples

This article reports a spectrofluorometric method for the determination of sunitinib (STB) drug based on molecularly imprinted nanofibers fabricated by the electrospinning method and modified by magnetic nanoparticles as sorbent. The characterization of magnetic molecularly imprinted nanofibers (MMINs) was carried out using X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM), which confirmed the successful synthesis of MMINs with well-distributed magnetite nanoparticles. Drug adsorption and desorption were optimized and important parameters such as sample pH, nanofiber mass, adsorption and desorption time, eluent solvent and sample volume were analyzed. The results demonstrated that the MMINs act as a selective sorbent for STB and can be readily collected through an external magnetic field. Methanol was used as the best eluent solvent for STB desorption from MNIN. A linear correlation was observed between the STB concentrations and fluorescence intensities in the range of 0.01-15.0 mg L-1. The detection limit for this method was 0.002 mg L-1. The relative standard deviation (RSD) of 2.6 % for 1.0 mg L-1 and 1.1 % for 10 mg L-1 of STB (n = 3) were obtained, which indicates that the developed method is precise in determining STB. Human serum and capsule analysis show the applicability of the proposed sensor for real samples.

PRRT in high-grade digestive neuroendocrine neoplasms (NET G3 and NEC)

Peptide receptor radionuclide therapy (PRRT) has been primarily studied in low and intermediate-grade digestive neuroendocrine tumors (NET G1-G2). The documentation of a similar benefit for high-grade digestive neuroendocrine neoplasms (NEN) has been limited. This review evaluates the use of PRRT for high-grade digestive NEN (well-differentiated NET G3 and poorly differentiated neuroendocrine carcinomas [NEC]). We identified one phase III trial and seven retrospective studies reporting specifically on PRRT outcome of >10 digestive high-grade NEN patients. The retrospective single-arm studies indicate a benefit for PRRT in NET G3. The randomized phase III NETTER-2 trial demonstrates major PFS superiority of PRRT versus somatostatin analog therapy as the first-line treatment for the NET G3 subgroup. PRRT can now be considered a potential first-line treatment for somatostatin receptor-positive NET G3 patients, but whether it should be the first-line standard of care for all NET G3 patients is still not clarified. For NEC, scarce data are available, and pathologic distinction between NEC and NET G3 can be difficult when Ki-67 is below 55%. PRRT could be considered as a treatment for refractory NEC in very selected cases when there is a high uptake on somatostatin receptor imaging, Ki-67 is below 55%, and there is no rapid tumor progression.

Prolonged Response to Dabrafenib/Trametinib in Grade 3 Metastatic Pancreatic Neuroendocrine Tumor (NET G3) with BRAF V600E Mutation

PURPOSE

Treatment of metastatic pancreatic neuroendocrine tumors (pancNETs), particularly grade 2 (G2) and grade 3 (G3), often presents a dilemma in choosing from multiple similarly efficacious therapies. Data on targeted therapies for these tumor types is limited, and this report presents BRAF-targeted therapy as a therapeutic option for metastatic pancNET G3.

METHODS

This is a case report of a patient with G3 pancNET metastatic to the liver, lung, lymph node, and scalp (soft tissue) treated with dabrafenib/trametinib (D/T) in the presence of a BRAF V600E mutation detected in tumor tissue.

RESULTS

This patient has demonstrated an ongoing partial response to therapy at all involved sites for nearly 15 months with minimal side effects attributable to D/T.

CONCLUSION

Dabrafenib/trametinib therapy for BRAF-mutated metastatic pancNETs provides a novel treatment option and, especially in the G3 setting, should be considered a first-line option. Tumor testing for actionable mutations should be undertaken at the time of diagnosis and/or progression to identify novel therapeutic avenues in these rare tumors.

Treatment modalities favoring outcome in well-differentiated neuroendocrine tumors G3

Introduction

Neuroendocrine neoplasms (NEN) are a rare and heterogenous group of tumors arising from neuroendocrine cells in multiple organs. Neuroendocrine tumors (NET) G3 encompass a small subgroup accounting for less than 10% of all neuroendocrine neoplasms. In contrast to NET G1 and G2 as well as neuroendocrine carcinomas (NEC), in NET G3 data on treatment and patient outcomes are still limited. Especially in a metastasized tumor stage, the role of surgery, peptide receptor radionucleotide therapy (PRRT), and systemic chemotherapy is not clearly defined.

Methods

In this real-life cohort, we consecutively analyzed clinical outcome in NET G3 patients receiving different diagnostic and treatment.

Results and discussion

We found that even metastasized NET G3 patients undergoing surgery, or receiving radiation, somatostatin analogues (SSA), and PRRT showed a clear survival benefit. Interestingly, all treatment regimen were superior to classical chemotherapeutic agents. In addition, somatostatin receptor (SSTR) PET-CT, FDG PET-CT, and repetitive biopsies were shown to be useful diagnostic and prognostic tools in NET G3. Our study demonstrates that patients with highly proliferative NET G3 might benefit from less aggressive treatment modalities commonly used in low proliferative NEN.

Tyrosine Kinase Inhibitors and Immunotherapy Updates in Neuroendocrine Neoplasms

Neuroendocrine tumors (NETs) represent a heterogeneous group of malignancies that arise from neuroendocrine cells dispersed throughout the organs/tissues of the body. Treatment of advanced/metastatic disease varies depending on tumor origin and grade. Somatostatin analogs (SSA) have been the mainstay first-line treatment in the advanced/metastatic setting for tumor control and managing hormonal syndromes. Treatments beyond SSAs have expanded to include everolimus (mTOR inhibitor), tyrosine kinase inhibitors (TKI) (e.g., sunitinib), and peptide receptor radionuclide therapy (PRRT) with the choice of therapy to some extent dictated by the anatomic origin of the NETs. This review will focus on emerging systemic treatments for advanced/metastatic NETs, particularly TKIs, and immunotherapy.

A systematic review of therapeutic strategies in gastroenteropancreatic grade 3 neuroendocrine tumors

Background

Gastroenteropancreatic (GEP) neuroendocrine neoplasms with Ki-67 > 20% were subdivided in the most recent 2019 World Health Organization histopathological classification into grade 3 (G3) neuroendocrine tumors (NETs), described as well-differentiated tumors, and neuroendocrine carcinomas, which are described as poorly differentiated tumors. This classification met the demand noted for different prognoses between these subgroups, prompting the need for treatment recommendations for well-differentiated G3 tumors.

Methods

We systematically searched medical literature databases and oncology conferences for studies on G3 GEP NET to describe epidemiology, diagnosis, molecular features, and treatments used. We excluded studies that did not discriminate G3 NET data. Data were tabulated and described, and a quality analysis of the reports was performed.

Results

We found 23 published studies and six abstracts; 89.7% of studies were retrospective, six were composed exclusively of G3 NETs. Among 761 patients, the median number of patients per study was 15, most were male and older than 60 years, and functional imaging tests were positive in more than 80% of cases. Overall, the scientific evidence supporting the treatment of G3 GEP NETs is limited. For localized disease, resection remains the standard treatment but there is no evidence to support neoadjuvant or adjuvant therapy. For advanced disease, capecitabine and temozolomide seems to be the most effective option, with a response rate, median progression-free survival, and median overall survival up to 37.9%, 20.6 months, and 41.2 months, respectively.

Conclusion

The latest available data on the epidemiology, diagnosis, molecular changes, and treatment of G3 GEP NET are described. Yet, the level of evidence for treatment recommendations is low, as most studies are retrospective. A treatment algorithm for G3 GEP NET is proposed.

The NET G3 enigma: dealing with a “new” entity

Neuroendocrine neoplasms of the gastroenteropancreatic system (GEP-NENs) have historically been graded into well-differentiated neuroendocrine tumors (NETs) G 1 and 2 and undifferentiated neuroendocrine carcinomas (NEC) G3 according to the proliferative index Ki-67, with the latter being larger than 20% for G3 NENs. However, clinical and pathological findings have suggested G3 NENs to be heterogeneous, and the most recent World Health Organization (WHO) classification has further subdivided G3 NENs into NET G3 with differentiated features and a usually lower Ki-67 (20–55%) as opposed to undifferentiated NECs. Currently, however, no standard approach to patients with NET G3 has been defined. As opposed to NET G1/G2, application of somatostatin analogues is not recommended, and the response to platinum-based chemotherapy is inferior when compared to NEC. The objective of this short review is to summarize pathological characteristics as well as therapeutic data obtained in patients with NET G3.

Surgical Outcomes, Long-Term Survivals and Staging Systems of World Health Organization G3 Pancreatic Neuroendocrine Tumors

Background: In 2017, the World Health Organization (WHO) defined a new category of pancreatic neuroendocrine neoplasms named G3 pancreatic neuroendocrine tumors (p-NETs), whose surgical outcomes, long-term survivals and staging systems have not been well documented. Methods: Data from eligible patients with G3 p-NETs defined using the WHO 2017 grading classification at our institute were retrospectively analyzed. Results: Our study enrolled 80 patients with WHO G3 p-NETs, including 50 women and 30 men. The accumulative 5-year overall survival (OS) of G3 p-NETs was 29.7%. The current staging system by the American Joint Committee on Cancer (AJCC) failed to discriminate the survival difference between Stage II and Stage III (p = 0.172), while notable differences with regard to the OS were statistically offered between each stage using the modified tumor−node−metastasis (mTNM) staging system (all p < 0.05). The OS of patients receiving surgical resection was significantly better than those with palliative operation (p < 0.05). Both the current AJCC system and proposed mTNM system were independent predictors for the OS of G3 p-NETs (p = 0.017 and p = 0.032, respectively). The 95% confidence intervals of the proposed mTNM staging system were smaller than that of the current AJCC system (0.626−8.217 and 0.329−10.013, respectively), indicating a relatively more accurate predictive ability. Conclusion: Our demonstration revealed that surgical resection was an independent predictor for the favorable prognosis of patients with G3 p-NETs. Moreover, the new mTNM staging system was more suitable and practical than the current AJCC system for stratifying G3 p-NETs into prognostic groups.

Treatment Approaches and Outcome of Patients with Neuroendocrine Neoplasia Grade 3 in German Real-World Clinical Practice

BACKGROUND

Neuroendocrine neoplasia grade 3 (NEN G3) represents a rare and heterogeneous cancer type with a poor prognosis. The aim of our study was to analyze real-world data from the German NET Registry with a focus on therapeutic and prognostic aspects.

METHODS

NEN G3 patients were identified within the German NET Registry. Demographic data and data on treatments and outcomes were retrieved. Univariate analyses were performed using the Kaplan-Meier-method. Multivariate analysis was performed using a Cox proportional hazard model.

RESULTS

Of 445 included patients, 318 (71.5%) were diagnosed at stage IV. Well-differentiated morphology (NET G3) was described in 31.7%, 60% of cases were classified as neuroendocrine carcinoma (NEC), and the median Ki67 value was 50%. First-line treatment comprised chemotherapy in 43.8%, with differences in the choice of regimen with regard to NET or NEC, and surgery in 41.6% of patients. Median overall survival for the entire cohort was 31 months. Stage, performance status and Ki67 were significant prognostic factors in multivariate analysis.

CONCLUSIONS

The survival data of our national registry compare favorably to population-based data, probably mainly because of a relatively low median Ki67 of 50%. Nevertheless, the best first- and second-line approaches for specific subgroups remain unclear, and an international effort to fill these gaps is needed.

Role of surgical treatments in high-grade or advanced gastroenteropancreatic neuroendocrine neoplasms

Over the last 40 years, the incidence and prevalence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have continued to increase. Compared to other epithelial neoplasms in the same organ, GEP-NENs exhibit indolent biological behavior, resulting in more chances to undergo surgery. However, the role of surgery in high-grade or advanced GEP-NENs is still controversial. Surgery is associated with survival improvement of well-differentiated high-grade GEP-NENs, whereas poorly differentiated GEP-NENs that may benefit from resection require careful selection based on Ki67 and other tissue biomarkers. Additionally, surgery also plays an important role in locally advanced and metastatic disease. For locally advanced GEP-NENs, isolated major vascular involvement is no longer an absolute contraindication. In the setting of metastatic GEP-NENs, radical intended surgery is recommended for patients with low-grade and resectable metastases. For unresectable metastatic disease, a variety of surgical approaches, including cytoreduction of liver metastasis, liver transplantation, and surgery after neoadjuvant treatment, show survival benefits. Primary tumor resection in GEP-NENs with unresectable metastatic disease is associated with symptom control, prolonged survival, and improved sensitivity toward systemic therapies. Although there is no established neoadjuvant or adjuvant strategy, increasing attention has been given to this emerging research area. Some studies have reported that neoadjuvant therapy effectively reduces tumor burden, improves the effectiveness of subsequent surgery, and decreases surgical complications.

Poor outcome after systemic therapy in secondary high-grade pancreatic neuroendocrine tumors

Longitudinal changes in pancreatic neuroendocrine tumor (panNET) cell proliferation correlate with fast disease progression and poor prognosis. The optimal treatment strategy for secondary panNET grade (G)3 that has progressed from a previous low- or intermediate-grade to high-grade panNET G3 is currently unknown. This was a single-center retrospective cohort study aimed to characterize treatment patterns and outcomes among patients with secondary panNET-G3. Radiological responses were assessed using the Response Evaluation Criteria in Solid Tumors version 1.1. A total of 22 patients were included and received a median of 2 (range, 1-4) treatment lines in 14 different combinations. Median overall survival (OS) was 9 months (interquartile range (IQR): 4.25-17.5). For the 15 patients who received platinum-etoposide chemotherapy, median OS was 7.5 months (IQR: 3.75-10) and median progression-free survival (PFS) was 4 months (IQR: 2.5-5.5). The 15 patients who received conventional panNET therapies achieved a median OS of 8 months (IQR: 5-16.75) and median PFS was 5.5 months (IQR: 2.75-8.25). We observed one partial response on 177Lu DOTA-TATE therapy. In conclusion, this hypothesis-generating study failed to identify any promising treatment alternatives for patients with secondary panNET-G3. This demonstrates the need for both improved biological understanding of this particular NET entity and for designing prospective studies to further assess its treatment in larger patient cohorts.

Predictive Factors for Resistant Disease with Medical/Radiologic/Liver-Directed Anti-Tumor Treatments in Patients with Advanced Pancreatic Neuroendocrine Neoplasms: Recent Advances and Controversies

Simple Summary

Tumor resistance, both primary and acquired, is leading to increased complexity in the nonsurgical treatment of patients with advanced panNENs, which would be greatly helped by reliable prognostic/predictive factors. The importance in identifying resistance is being contributed to by the increased array of possible treatments available for treating resistant advanced disease; the variable clinical course as well as response to any given treatment approach of patients within one staging or grading system, the advances in imaging which are providing increasing promising results/parameters that correlate with grading/outcome/resistance, the increased understanding of the molecular pathogenesis providing promising prognostic markers, all of which can contribute to selecting the best treatment to overcome resistance disease. Several factors have been identified that have prognostic/predictive value for identifying development resistant disease and affecting overall survival (OS)/PFS with various nonsurgical treatments of patients with advanced panNENs. Prognostic factors identified for patients with advanced panNENs for both OS/PFSs include various clinically-related factors (clinical, laboratory/biological markers, imaging, treatment-related factors), pathological factors (histological, classification, grading) and molecular factors. Particularly important prognostic factors for the different treatment modalities studies are the recent grading systems. Most prognostic factors for each treatment modality for OS/PFS are not specific for a given treatment option. These advances have generated several controversies and new unanswered questions, particularly those related to their possible role in predicting the possible sequence of different anti-tumor treatments in patients with different presentations. Each of these areas is reviewed in this paper.

Abstract

Purpose: Recent advances in the diagnosis, management and nonsurgical treatment of patients with advanced pancreatic neuroendocrine neoplasms (panNENs) have led to an emerging need for sensitive and useful prognostic factors for predicting responses/survival. Areas covered: The predictive value of a number of reported prognostic factors including clinically-related factors (clinical/laboratory/imaging/treatment-related factors), pathological factors (histological/classification/grading), and molecular factors, on therapeutic outcomes of anti-tumor medical therapies with molecular targeting agents (everolimus/sunitinib/somatostatin analogues), chemotherapy, radiological therapy with peptide receptor radionuclide therapy, or liver-directed therapies (embolization/chemoembolization/radio-embolization (SIRTs)) are reviewed. Recent findings in each of these areas, as well as remaining controversies and uncertainties, are discussed in detail, particularly from the viewpoint of treatment sequencing. Conclusions: The recent increase in the number of available therapeutic agents for the nonsurgical treatment of patients with advanced panNENs have raised the importance of prognostic factors predictive for therapeutic outcomes of each treatment option. The establishment of sensitive and useful prognostic markers will have a significant impact on optimal treatment selection, as well as in tailoring the therapeutic sequence, and for maximizing the survival benefit of each individual patient. In the paper, the progress in this area, as well as the controversies/uncertainties, are reviewed.

Therapeutic strategies for gastroenteropancreatic neuroendocrine neoplasms: State-of-the-art and future perspectives

Although gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) have always been considered rare tumors, their incidence has risen over the past few decades. They represent a highly heterogeneous group of neoplasms with several prognostic factors, including disease stage, proliferative index (Ki67), and tumor differentiation. Most of these neoplasms express somatostatin receptors on the cell surface, a feature that has important implications in terms of prognosis, diagnosis, and therapy. Although International Guidelines propose algorithms aimed at guiding therapeutic strategies, GEP-NEN patients are still very different from one another, and the need for personalized treatment continues to increase. Radical surgery is always the best option when feasible; however, up to 80% of cases are metastatic upon diagnosis. Regarding medical treatments, as GEP-NENs are characterized by relatively long overall survival, multiple therapy lines are adopted during the lifetime of these patients, but the optimum sequence to be followed has never been clearly defined. Furthermore, although new molecular markers aimed at predicting the response to therapy, as well as prognostic scores, are currently being studied, their application is still far from being part of daily clinical practice. As they represent a complex disease, with therapeutic protocols that are not completely standardized, GEP-NENs require a multidisciplinary approach. This review will provide an overview of the available therapeutic options for GEP-NENs and attempts to clarify the possible approaches for the management of these patients and to discuss future perspectives in this field.

Incidence, prevalence, and survival trends for neuroendocrine neoplasms in Victoria, Australia, from 1982 to 2019: Based on site, grade, and region

AIMS

Neuroendorcine neoplasms (NENs) are rare tumors characterised by variable biology and delayed diagnosis. Several population studies have reported a marked increased incidence over time. The objectives of this analysis were to describe within Victoria (the second largest Australian state, 6.4 Million) the trends for NENs incidence/survival over nearly 38 years (1982-2019), and regional differences in survival.

METHODS

All NEN cases were identified from the Victorian Cancer Registry over four time periods: 1982-1989, 1990-1999, 2000-2009, and 2010-2019. Data collected included primary tumor site, histological grade, gender, overall survival (OS), and place of residence. Incidence data were analyzed with the generation of annual standardized rates (ASR). OS was assessed for the entire cohort and between geographical regions.

RESULTS

The overall NEN population (1982-2019) included 8,106 patients: over 60% grade 1/2 NENs, especially small bowel and colorectal. The number of new diagnoses increased over three-fold over time for the overall cohort and by tumoral categories. The ASR increased similarly, especially pancreatic NENs (4.3-fold) and differed between genders. The 5-year OS rates and median OS increased over time for the overall cohort: from 52% to 67% (p < 0.001). OS was greater for NEN patients residing in major cities relative to regional/remote areas (p = 0.01).

CONCLUSION

This population-wide analysis with over 38 years of data has confirmed the international trends of the increased incidence, prevalence, and OS of NEN patients regardless of primary site or histological grade. The analysis also observed a difference in survival outcome in rural/remote versus urban areas.

Identification of Candidate Biomarker ASXL2 and Its Predictive Value in Pancreatic Carcinoma

Pancreatic adenocarcinoma is one of the most lethal diseases with a 5-year survival rate of about 8%. ASXL2 is an epigenetic regulator associated with various tumors including colorectal cancer, breast cancer, and myeloid leukemia. However, the role of ASXL2 in pancreatic cancer remains unclear. This is the first research focusing on the prognostic value of ASXL2 in pancreatic cancer. In this research, we aimed to explore the correlation between ASXL2 and the prognosis, as well as other features in PAAD. We obtained gene expression profiles of PAAD and normal tissues from TCGA, GEO, and Xena databases. TIMER and CIBERSORT algorithms were employed to investigate the effect of ASXL2 on tumor microenvironment. GSEA along with GO and KEGG enrichment analyses were conducted to uncover the biological functions of ASXL2. The response to various chemotherapeutic drugs was estimated by algorithms in R package “pRRophetic”, while the sensitivity to immunotherapy was quantified by TIDE score. We found that ASXL2 was upregulated in the PAAD samples and elevated expression of ASXL2 was linked to poor overall survival. ASXL2 DNA methylation contributed to ASXL2 expression. Functional annotation indicated that ASXL2 was mainly involved in inflammatory response and epithelial mesenchymal transition. Patients with high ASXL2 expression were more likely to benefit from immune checkpoint blockade, gemcitabine, and mitomycin-C. Finally, external datasets and biospecimens were used and the results further validated the aberrant expression of ASXL2 in PAAD samples. In summary, our results highlight that ASXL2 is a potential prognostic and predictive biomarker in pancreatic cancer.

Gastroenteropancreatic neuroendocrine neoplasms G3: Novel insights and unmet needs

According to the 2019 WHO pathology grading system, high-grade gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) can be divided into well differentiated neuroendocrine tumors G3 (NETs G3) and poorly differentiated neuroendocrine carcinomas (NECs). GEP-NETs G3 and GEP-NECs present significant differences in driver genes and disease origin. NETs G3 and NECs have been confirmed to be two distinct diseases with different genetic backgrounds, however, this issue remains controversial. The prognosis of NETs G3 is significantly better than that of NECs. The differential diagnosis of GEP-NETs G3 and GEP-NECs should be combined with the patient's medical history, tumor histopathology, Ki-67 index, DAXX/ATRX, TP53 and Rb expression as well as other immunohistochemical indicators. In addition, the treatment strategies of these two subgroups are very different. Here, we summarize recent findings focused on the genomics, clinical manifestations, diagnosis, treatment and other aspects of high-grade GEP-NENs (G3). This review may help further our understanding of the carcinogenesis, diagnosis and treatment of GEP-NENs G3.

Well-differentiated gastroenteropancreatic G3 NET: findings from a large single centre cohort

Neuroendocrine neoplasms are known to have heterogeneous biological behavior. G3 neuroendocrine tumours (NET G3) are characterized by well-differentiated morphology and Ki67 > 20%. The prognosis of this disease is understood to be intermediate between NET G2 and neuroendocrine carcinoma (NEC). Clinical management of NET G3 is challenging due to limited data to inform treatment strategies. We describe clinical characteristics, treatment, and outcomes in a large single centre cohort of patients with gastroenteropancreatic NET G3. Data was reviewed from 26 cases managed at Queen Elizabeth Hospital, Birmingham, UK, from 2012 to 2019. Most commonly the site of the primary tumour was unknown and majority of cases with identifiable primaries originated in the GI tract. Majority of cases demonstrated somatostatin receptor avidity. Median Ki67 was 30%, and most cases had stage IV disease at diagnosis. Treatment options included surgery, somatostatin analogs (SSA), and chemotherapy with either platinum-based or temozolomide-based regimens. Estimated progression free survival was 4 months following initiation of SSA and 3 months following initiation of chemotherapy. Disease control was observed following treatment in 5/11 patients treated with chemotherapy. Estimated median survival was 19 months; estimated 1 year survival was 60% and estimated 2 year survival was 13%. NET G3 is a heterogeneous group of tumours and patients which commonly have advanced disease at presentation. Prognosis is typically poor, though select cases may respond to treatment with SSA and/or chemotherapy. Further study is needed to compare efficacy of different treatment strategies for this disease.

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.

Treatment of advanced gastroenteropancreatic neuroendocrine neoplasia, are we on the way to personalised medicine?

Gastroenteropancreatic neuroendocrine neoplasia (GEPNEN) comprises clinically as well as prognostically diverse tumour entities often diagnosed at late stage. Current classification provides a uniform terminology and a Ki67-based grading system, thereby facilitating management. Advances in the study of genomic and epigenetic landscapes have amplified knowledge of tumour biology and enhanced identification of prognostic and potentially predictive treatment subgroups. Translation of this genomic and mechanistic biology into advanced GEPNEN management is limited. 'Targeted' treatments such as somatostatin analogues, peptide receptor radiotherapy, tyrosine kinase inhibitors and mammalian target of rapamycin inhibitors are treatment options but predictive tools are lacking. The inability to identify clonal heterogeneity and define critical oncoregulatory pathways prior to therapy, restrict therapeutic efficacy as does the inability to monitor disease status in real time. Chemotherapy in the poor prognosis NEN G3 group, though associated with acceptable response rates, only leads to short-term tumour control and their molecular biology requires delineation to provide new and more specific treatment options.The future requires an exploration of the NEN tumour genome, its microenvironment and an identification of critical oncologic checkpoints for precise drug targeting. In the advance to personalised medical treatment of patients with GEPNEN, clinical trials need to be based on mechanistic and multidimensional characterisation of each tumour in order to identify the therapeutic agent effective for the individual tumour.This review surveys advances in NEN research and delineates the current status of translation with a view to laying the basis for a genome-based personalised medicine management of advanced GEPNEN.

Treatment Outcomes of Well-Differentiated High-Grade Neuroendocrine Tumors

INTRODUCTION

Recent classification of neuroendocrine neoplasms has defined well-differentiated high-grade neuroendocrine tumors (NET G3) as a distinct entity from poorly differentiated neuroendocrine carcinoma. The optimal treatment for NET G3 has not been well-described. This study aimed to evaluate metastatic NET G3 response to different treatment regimens.

MATERIALS AND METHODS

This was a retrospective study of patients with NET G3 within the Mayo Clinic database. Patients' demographics along with treatment characteristics, responses, and survival were assessed. Primary endpoints were progression-free survival (PFS) and overall survival. Secondary endpoints were objective response rate (ORR) and disease control rate (DCR).

RESULTS

Treatment data was available in 30 patients with median age of 59.5 years at diagnosis. The primary tumor was mostly pancreatic (73.3%). Ki-67 index was ≥55% in 26.7% of cases. Treatments included capecitabine + temozolomide (CAPTEM) (n = 20), lutetium 177 DOTATATE (PRRT; n = 10), Platinum-etoposide (EP; n = 8), FOLFOX (n = 7), and everolimus (n = 2). CAPTEM exhibited ORR 35%, DCR 65%, and median PFS 9.4 months (95% confidence interval, 2.96-16.07). Both EP and FOLFOX showed similar radiographic response rates with ORR 25.0% and 28.6%; however, median PFS durations were quite distinct at 2.94 and 13.04 months, respectively. PRRT had ORR of 20%, DCR of 70%, and median PFS of 9.13 months.

CONCLUSION

Among patients with NET G3, CAPTEM was the most commonly used treatment with clinically meaningful efficacy and disease control. FOLFOX or PRRT are other potentially active treatment options. EP has some activity in NET G3, but responses appear to be short-lived. Prospective studies evaluating different treatments effects in patients with NET G3 are needed to determine an optimal treatment strategy.

IMPLICATIONS FOR PRACTICE

High-grade well-differentiated neuroendocrine tumors (NET G3) are considered a different entity from low-grade NET and neuroendocrine carcinoma in terms of prognosis and management. The oral combination of capecitabine and temozolomide is considered a good option in the management of metastatic NET G3 and may be preferred. FOLFOX is another systemic option with reasonable efficacy. Similar to other well-differentiated neuroendocrine tumors, peptide receptor radionuclide therapy seems to have some efficacy in these tumors.

Sunitinib malate inhibits intestinal tumor development in male ApcMin/+ mice by down-regulating inflammation-related factors with suppressing β-cateinin/c-Myc pathway and re-balancing Bcl-6 and Caspase-3

Sunitinib is a tyrosine kinase inhibitor for many tumors. Inflammation is one of the most important factors in the development of intestinal tumors. Many inflammation-related factors are regulated by tyrosine kinase receptors. It is reasonable to hypothesize that sunitinib can regulate the development of intestinal tumors by regulating the expression and/or activity of inflammation-related factors. Here, ApcMin/+ male mouse model was used to investigate the effect and mechanism of sunitinib malate against intestinal cancer. Results show that compared to vehicle, after sunitinib malate treatment, overall survival of ApcMin/+ mice was lengthened up to 25 days, with a gain of body weight, reduction of spleen/body weight index, and RBC, WBC and HGC regulated to normal levels of wild type mice, and a number of polyps no less than 1 mm significantly reduced. Meanwhile, in the intestines, the nuclear β-Catenin protein and c-Myc mRNA were both down-regulated, and Bcl-6 was significantly reduced with Caspase-3 up regulated. Furthermore, inflammation-related factors including IL-6, TNF-α, IL-1α, IL-1β and IFN-γ were down-regulated at mRNA levels in the intestines. These results suggest that sunitinib malate can significantly improve the survival status and inhibit intestinal tumor development in male ApcMin/+ mice, through inhibiting inflammation-related factors, while suppressing β-cateinin/c-Myc pathway and re-balancing protein levels of Bcl-6 and Caspase-3.

A comprehensive validation of the novel 8th edition of American Joint Committee on Cancer staging manual for the long-term survivals of patients with non-functional pancreatic neuroendocrine neoplasms

Histologically, the World Health Organization has classified pancreatic neuroendocrine neoplasms (p-NENs) into well-differentiated pancreatic neuroendocrine tumors (G1/G2 p-NETs) and poorly-differentiated pancreatic neuroendocrine carcinoma (G3 p-NECs) based on tumor mitotic counts and Ki-67 index. Recently, the 8th edition of American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) staging manual has incorporated some major changes in 2017 that the TNM staging system for p-NENs should only be applied to well-differentiated G1/G2 p-NETs, while poorly-differentiated G3 p-NECs be classified according to the new system for pancreatic exocrine adenocarcinomas. However, this new manual for p-NENs has seldom been evaluated.Data of patients with both G1/G2 and G3 non-functional p-NENs (NF-p-NENs) from our institution was retrospectively collected and analyzed using 2 new AJCC 8th staging systems. We also made survival comparisons between the 8th and 7th edition system separately for different subgroups.For G1/G2 NF-p-NETs, there were 52 patients classified in AJCC 8th edition stage I, 40 in stage II, 41 in stage III and 19 in stage IV. As for G3 NF-p-NECs, 17, 19, 24, and 18 patients were respectively defined from AJCC 8th edition stage I to stage IV. In terms of the AJCC 7th staging system, the 230 patients with NF-p-NENs were totally distributed from stage I to stage IV (94, 63, 36, 37, respectively). For the survival analysis of both G1/G2 NF-p-NETs and G3 NF-p-NECs, the AJCC 7th edition system failed to discriminate the survival differences when compared stage III with stage II or stage IV (P > .05), while the 8th edition ones could perfectly allocate patients into 4 statistically different groups (P < .05). The HCIs of AJCC 8th stage for G1/G2 NF-p-NETs [HCI=0.658, 95% confidence interval (CI)=0.602-0.741] and stage for G3 NF-p-NECs (HCI=0.704, 95% CI=0.595-0.813) was both statistically larger than those of AJCC 7th stage for different grading NF-p-NENs [(HCI=0.578, 95% CI=0.557-0.649; P=.031), (HCI=0.546, 95% CI=0.531-0.636; P = .019); respectively], indicating a more accurate predictive ability for the survivals of NF-p-NENs.Our data suggested the 2 new AJCC 8th staging systems were superior to its 7th edition for patients with both G1/G2 NF-p-NETs and G3 NF-p-NECs.

Pancreatic neuroendocrine carcinoma G3 may be heterogeneous and could be classified into two distinct groups

BACKGROUND/OBJECTIVES

Pancreatic neuroendocrine carcinoma (PanNEC)-G3 often presents along with genetic abnormalities such as KRAS, RB1, and TP53 mutations. However, the association between these genetic findings and response to chemotherapy and prognosis has not been clarified. This study aimed to clarify the clinicopathological features of PanNEC-G3.

METHODS

We performed a subgroup analysis of the Japanese PanNEN-G3 study (multicenter, retrospective study), which revealed that Rb loss and KRAS mutation were predictors of the response to platinum-based regimen in PanNEN-G3. We re-classified WHO grades of PanNENs using the 2017 WHO classification and then analyzed the clinicopathological features and prognostic factors in 49 patients with PanNEC-G3.

RESULTS

The rates of Rb loss and KRAS mutation in PanNEC-G3 were 54.5% and 48.7%, respectively. Patients with Rb loss and/or KRAS mutation showed a higher response rate to first-line platinum-based regimen than those without Rb loss or KRAS mutation (object response rate 70.0% vs 33.3%, odds ratio 9.22; 95% CI 1.26-67.3, P = 0.029), but tended to have shorter overall survival rates than those without Rb loss or KRAS mutation (median 239 vs 473 days, hazard ratio 2.11; 95% CI 0.92-4.86, P = 0.077).

CONCLUSIONS

Patients with PanNEC-G3 have varied clinical outcomes for platinum-based regimen. When grouped based on Rb loss and KRAS mutation, there seemed to be two groups with distinct prognoses and responses to the platinum-based regimen. PanNEC-G3 could, therefore, be classified into two distinct groups based on immunohistochemical and genetic findings.

The North American Neuroendocrine Tumor Society Consensus Guidelines for Surveillance and Medical Management of Pancreatic Neuroendocrine Tumors

This article is the result of the North American Neuroendocrine Tumor Society consensus conference on the medical management of pancreatic neuroendocrine tumors from July 19 to 20, 2018. The guidelines panel consisted of medical oncologists, pathologists, gastroenterologists, endocrinologists, and radiologists. The panel reviewed a series of questions regarding the medical management of patients with pancreatic neuroendocrine tumors as well as questions regarding surveillance after resection. The available literature was reviewed for each of the question and panel members voted on controversial topics, and the recommendations were included in a document circulated to all panel members for a final approval.

Survivals of patients with pancreatic neuroendocrine carcinomas: An in-depth analysis by the American Joint Committee on Cancer 8th tumor-node-metastasis staging manual

Recently, the American Joint Committee on Cancer (AJCC) 8th staging manual stipulated the World Health Organization (WHO) G3 pancreatic neuroendocrine carcinomas (p-NECs) should all be classified by the system for pancreatic exocrine adenocarcinomas, which had ignored the heterogeneity of G3 p-NECs. We focused on demonstrating whether the heterogeneous subgroups of G3 p-NECs would influence the accurate application of AJCC 8th staging systems.G3 p-NECs were divided into well-differentiated and poorly-differentiated subgroups, whose clinical features and overall survival (OS) were compared. Survival analysis by applying 2 new AJCC 8th staging systems to well-differentiated G3 p-NECs were performed to validate whether these subgroup patients should also be staged by the system proposed for all G3 p-NECs.We enrolled 172 patients who were histopathologically diagnosed as G3 p-NECs, including 64 well-differentiated G3 p-NECs and 108 poorly-differentiated ones, whose patient demographics and tumor characteristics present no notably differences (P > .05), except their Ki-67 index and mitotic rate (P = .031, P = .025; respectively). The estimated OS of well-differentiated G3 p-NECs was significantly better than those of poorly-differentiated tumors (P < .001). When applying the new AJCC system for all G3 p-NECs to well-differentiated G3 tumors, 18, 22, 12, and 12 patients were respectively distributed in the new AJCC Stage I, Stage II, Stage III, and Stage IV. Using the AJCC 8th staging system for WHO G1/G2 pancreatic neuroendocrine tumors (p-NETs) to well-differentiated G3 p-NECs, there were 5, 25, 22, and 12 patients classified from the new AJCC Stage I to Stage IV, respectively. The system for G1/G2 p-NETs could significantly differentiate the survival differences between each new stage of well-differentiated G3 p-NECs (P < .05), while comparisons of survivals between Stage II with Stage III or Stage III with Stage IV by the system for G3 p-NECs were not statistically different (P = .334, P = .073; respectively).G3 p-NECs were heterogeneous with well-differentiated and poorly-differentiated subgroups. Both AJCC 8th staging systems proposed for all G3 p-NECs and G1/G2 p-NETs were practical for well-differentiated G3 p-NECs, while the one originally applied to G1/G2 p-NETs appeared to be superior in performance due to its better prognostic stratification and more accurate predicting ability.

Combination of weekly streptozocin and oral S-1 treatment for patients of unresectable or metastatic pancreatic neuroendocrine neoplasms

BACKGROUND

Streptozocin (STZ) administration with or without other cytotoxic drugs remains a crucial chemotherapy for patients with advanced pancreatic neuroendocrine neoplasms (Pan-NENs). However, the therapeutic effects of combination treatment with weekly STZ and oral S-1 therapy (STS1) remain unknown. Therefore, the aim of this study was to evaluate the safety and clinical feasibility of STS1.

METHODS

Twenty of 243 Pan-NEN patients were included in this retrospective study, all of whom had received STS1 for unresectable or distant metastatic diseases from November 2015 to January 2019. The maximum tumor shrinkage rate, time course of the tumor shrinkage rate, prognosis (progression-free survival and overall survival), and adverse events were evaluated.

RESULTS

The median age of the patients was 61.5 years and the median tumor size was 35 mm. The number of NET-G1, NET-G2, NET-G3, and NEC-G3 patients was 3, 13, 3, and 1, respectively. The median Ki-67 index and mitoses were 10.2% and 2/10 high-power fields, respectively. The overall objective response rate and disease control rate were 30% and 90%, respectively. The median maximum tumor reduction rate was 19%. The Ki-67 index and tumor size did not influence the tumor shrinkage rate. Progression-free survival after STS1 treatment was 19 months with no significant difference between NET-G1/G2 and NET-G3/NEC-G3 patients (p = 0.4). There was one case each of grade 3/4 toxicity, including general fatigue, hyperglycemia, and renal dysfunction. No serious myelosuppressive events are manifested.

CONCLUSIONS

STS1 treatment is an effective and safe therapeutic option for patients with advanced Pan-NEN.

Management of Well-Differentiated High-Grade (G3) Neuroendocrine Tumors

OPINION STATEMENT

In 2017, the World Health Organization (WHO) classification for pancreatic NET was updated to include a new category of well-differentiated high-grade (Ki 67 > 20%) pancreatic tumors (NET G3), distinct from high-grade poorly differentiated neuroendocrine carcinoma (NEC). NET G3 are considered a molecularly, radiologically, and prognostically distinct entity compared to NEC and NET G1/G2. The optimal first-line management in NET G3 and sequencing therapies remains a challenge awaiting future trials taking into consideration the unique characteristics of this category. In this review, we aim to summarize the current evidence in the management of NET G3.

Pharmacogenomic analyses of sunitinib in patients with pancreatic neuroendocrine tumors

Aim: Evaluate associations between clinical outcomes and SNPs in patients with well-differentiated pancreatic neuroendocrine tumors receiving sunitinib. Patients & methods: Kaplan–Meier and Cox proportional hazards models were used to analyze the association between SNPs and survival outcomes using data from a sunitinib Phase IV (genotyped, n = 56) study. Fisher’s exact test was used to analyze objective response rate and genotype associations. Results: After multiplicity adjustment, progression-free and overall survivals were not significantly correlated with SNPs; however, a higher objective response rate was significantly associated with IL1B rs16944 G/A versus G/G (46.4 vs 4.5%; p = 0.001). Conclusion: IL1B SNPs may predict treatment response in patients with pancreatic neuroendocrine tumors. VEGF pathway SNPs are potentially associated with survival outcomes.

Does sunitinib have a patient-specific dose without diminishing its antitumor effect on advanced pancreatic neuroendocrine neoplasms?

PURPOSE

Because it is unknown whether adjusting the dose of sunitinib can benefit patients with pancreatic neuroendocrine neoplasms (Pan-NENs), this retrospective study examined maximum tumor shrinkage rates and prognoses in patients with and without low doses of sunitinib administration.

METHODS

Eighty-seven patients with metastatic and unresectable neoplasms, treated with sunitinib for > 1 month, were divided into a low-dose (LD) or high-dose (HD) group. The tumor response rates were investigated over time using computed tomography according to the response evaluation criteria in solid tumors criteria.

RESULTS

The LD and HD groups included 42 and 45 patients, respectively. There were no differences in baseline characteristics (tumor size, Ki-67 index, mitosis, and differentiation) between the two groups. Progressive disease (PD), stable disease (SD), and partial response (PR) were observed in 16.7, 54.8, and 28.6% of patients in the LD group, respectively, and in 13.3, 60, and 26.7% of patients in the HD group, respectively. There were no differences in tumor shrinkage rates between the two groups (p = 0.87). The 3-year progression-free survival rates for the LD and HD groups were 2.4% and 2.3%, respectively (p = 0.67), and the 3-year overall survival rates were 57.9% and 70.5%, respectively (p = 0.76). The occurrence of adverse events was similar between the two groups (61.9% vs. 60.0%, p > 0.95).

CONCLUSIONS

Dose reduction of sunitinib did not alter tumor shrinkage rates or prognoses for patients with advanced Pan-NENs.

Survivals of patients with surgically treated and High-grade pancreatic neuroendocrine carcinomas: A comparative study between two American Joint Committee on Cancer 8th tumor-node-metastasis staging systems

BACKGROUND AND OBJECTIVE

We aimed to compare the two new defined tumor-node-metastasis (TNM) systems in the American Joint Committee on Cancer (AJCC) 8th staging manual for overall survival (OS) analysis of G3 pancreatic neuroendocrine carcinomas (p-NECs) that are currently proposed for pancreatic exocrine adenocarcinomas (p-EACs) and G1/G2 pancreatic neuroendocrine tumors (p-NETs), respectively.

METHODS

The data of patients who were surgically treated and histopathologically diagnosed with G3 p-NECs at West China Hospital of Sichuan University from January 2002 to June 2017 were retrospectively analyzed and compared using the two new AJCC staging systems.

RESULTS

Applying the p-EAC AJCC 8th TNM staging system to G3 p-NECs, the estimated 3-year OSs for each stage were 86.7%, 76.0%, 44.5% and 20.7%, respectively (P < 0.001). According to the G1/G2 p-NETs staging system, the estimated OSs at 3 years for each new AJCC stage were 100.0%, 83.6%, 47.1% and 20.7%, respectively (P < 0.001). The system for p-EACs significantly discriminated the survival difference of G3 p-NECs between Stage I and Stage II (P = 0.019), while the other one for G1/G2 p-NETs could not (P = 0.108). The consistent results of Akaike information criteria with Harrell's concordance index indicated that the AJCC 8th staging system for p-EACs was superior when applied to G3 p-NECs for its better prognostic stratification and more accurate prediction ability for OS.

CONCLUSIONS

Our analysis demonstrated that both TNM systems in the AJCC 8th staging manual were prognostic for patients with G3 p-NECs; however, the classification originally applied to p-EACs was superior and supported its use in clinical practice.