Clinical Presentation and Diagnosis of Neuroendocrine Tumors. Hematol Oncol Clin North Am. 2016;30:21-48. [PMID: 26614367 DOI: 10.1016/j.hoc.2015.08.006]

Surgical Management of Neuroendocrine Tumor Liver Metastases

Patients with neuroendocrine tumor liver metastases (NETLMs) may develop carcinoid syndrome, carcinoid heart disease, or other symptoms from overproduction of hormones. Hepatic resection and cytoreduction is the most direct treatment of NETLMs in eligible patients, and cytoreduction improves symptoms, may reduce the sequelae of carcinoid syndrome, and extends survival. Parenchymal-sparing procedures, such as ablation and enucleation, should be considered during cytoreduction to maximize treatment of multifocal tumors while preserving healthy liver tissue. For patients with large hepatic tumor burdens, high-grade disease, or comorbidities precluding surgery, liver-directed and systemic therapies can be used to palliate symptoms and improve progression-free survival.

The Role of Small-Bowel Endoscopy in the Diagnosis and Management of Small-Bowel Neuroendocrine Tumours

Neuroendocrine tumours (NETs) are relatively rare neoplasms but represent one of the most frequent types of primary small-bowel tumours. Their incidence is rising, and this is most likely because of their more frequent early-stage detection, physician awareness, and increasing availability and use of imaging and small-bowel endoscopic techniques, such as video capsule endoscopy and device-assisted enteroscopy, which enable the detection, localisation, and histological sampling of previously inaccessible and underdiagnosed small-bowel lesions. This review summarises the role of small-bowel endoscopy in the diagnosis and management of small-bowel NETs to assist clinicians in their practice. Small-bowel endoscopy may play a complementary role in the diagnosis of these tumours alongside other diagnostic tests, such as biomarkers, conventional radiology, and functional imaging. In addition, small-bowel enteroscopy may play a role in the preoperative setting for the identification and marking of these tumours for surgical resection and the management of rare complications, such as small-bowel variceal bleeding, in cases of portal hypertension due to the encasement of mesenteric vessels in fibrotic small-bowel NETs.

Liver metastasized pancreatic neuroendocrine tumor in a 17-year-old female: A case report

Key Clinical Message

Pancreatic neuroendocrine tumors (PNETs) are rare and often misdiagnosed due to their vague symptoms and tumor heterogeneity. Early detection using computed tomography (CT) is essential, particularly in regions without access to advanced diagnostic tools like immunohistochemistry and genetic testing.

Abstract

Neuroendocrine tumors (NETs) are rare tumors in adults and extremely rare in the pediatric population, as pancreatic NETs (pNETs) have an incidence rate of <0.1 per million. We present a case of a 17-year-old female with a liver metastasized pNET. A 17-year-old female with a history of intermittent abdomen-back pain presented to the clinic with severe upper abdominal pain radiating to the shoulder. The routine tests were normal. An ultrasound showed multiple lesions in the liver, which were confirmed by a computed tomography (CT) that uncovered a pancreatic lesion too. A liver biopsy proved it was a metastasized pNET with positive NET markers on IMC staining. The metaiodobenzylguanidine (MIBG) scan flared the liver lesion. The patient was started on Octreotide long-acting release (LAR) 30 mg once monthly. The rarity of these tumors makes their diagnosis difficult, but they should not be omitted and must be considered when there are long-lasting symptoms that are not compatible with common illnesses. These tumors are curable in their early stages.

Gastroenteropancreatic neuroendocrine neoplasms: epidemiology, genetics, and treatment

The incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP NEN) is increasing at a rapid pace and is becoming an increasingly important consideration in clinical care. Epidemiological data from multiple countries indicate that the incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP NEN) exhibits regional, site-specific, and gender-based variations. While the genetics and pathogenesis of some GEP NEN, particularly pancreatic NENs, have been investigated, there are still many mechanisms that require further investigation. The management of GEP NEN is diverse, but surgery remains the primary option for most cases. Peptide receptor radionuclide therapy (PRRT) is an effective treatment, and several clinical trials are exploring the potential of immunotherapy and targeted therapy, as well as combination therapy.

Entinostat in patients with relapsed or refractory abdominal neuroendocrine tumors

BACKGROUND

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare neoplasms with an increasing annual incidence and prevalence. Many are metastatic at presentation or recur following surgical resection and require systemic therapy, for which somatostatin analogs such as octreotide or lanreotide comprise typical first-line therapies. Nonetheless, treatment options remain limited. Epigenetic processes such as histone modifications have been implicated in malignant transformation and progression. In this study, we evaluated the anti-proliferative effects of a histone deacetylase (HDAC) inhibitor, entinostat, which was computationally predicted to show anti-cancer activity, as confirmed in in vitro and in vivo models of GEP-NETs.

METHODS

This was a phase II study to evaluate the efficacy and safety of entinostat in patients with relapsed or refractory abdominal NETs. The primary objective was to estimate the objective response rate to entinostat. Additionally, with each patient as his/her own control we estimated the rates of tumor growth prior to enrollment on study and while receiving entinostat. Patients received 5 mg entinostat weekly until disease progression or intolerable toxicity. The dose could be changed to 10 mg biweekly for patients who did not experience grade ≥ 2 treatment-related adverse events (AEs) in cycle 1, but was primarily administered at the starting 5 mg weekly dose.

RESULTS

The study enrolled only 5 patients due to early termination by the drug sponsor. The first patient that enrolled had advanced disease and died within days of enrollment before follow-up imaging due to a grade 5 AE unrelated to study treatment and was considered non-evaluable. Best RECIST response for the remaining 4 patients was stable disease (SD) with time on study of 154+, 243, 574, and 741 days. With each patient as his/her own control, rates of tumor growth on entinostat were markedly reduced with rates 17%, 20%, 33%, and 68% of the rates prior to enrollment on study. Toxicities possibly or definitely related to entinostat included grade 2/3 neutrophil count decrease [2/4 (50%)/ 2/4 (50%)], grade 3 hypophosphatemia [1/4, (25%)], grade 1/2 fatigue [1/4 (25%)/ 2/4 (50%)], and other self-limiting grade 1/2 AEs.

CONCLUSION

In the treatment of relapsed or refractory abdominal NETs, entinostat 5 mg weekly led to prolonged SD and reduced the rate of tumor growth by 32% to 83% with an acceptable safety profile (ClinicalTrials.gov Identifier: NCT03211988).

The Role of Inositols in Endocrine and Neuroendocrine Tumors

Inositols have demonstrated a role in cancer prevention and treatment in many kinds of neoplasms. Their molecular mechanisms vary from the regulation of survival and proliferative pathways to the modulation of immunity and oxidative stress. The dysregulation of many pathways and mechanisms regulated by inositols has been demonstrated in endocrine and neuroendocrine tumors but the role of inositol supplementation in this context has not been clarified. The aim of this review is to summarize the molecular basis of the possible role of inositols in endocrine and neuroendocrine tumors, proposing it as an adjuvant therapy.

[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.

Neuroendocrine carcinoma of tonsil presented with axillary lymph node metastasis: Management dilemma

ABSTRACT

High-grade neuroendocrine carcinoma (NEC) of the tonsil is rare and has a poor prognosis. The usual presentation is a neck mass with locoregional cervical lymphadenopathy. An axillary lymphadenopathy as a primary presentation of NEC of the tonsils is uncommon and challenging to treat. Tonsil neuroendocrine tumors display aggressive behaviors associated with early recurrence and metastasis after surgical resection. Managing this condition is demanding compared to NECs of gastrointestinal origin since, to date, the management of head-and-neck neuroendocrine tumors is still not well established. We present a 49-year-old female with a rare case of NEC of the tonsil presenting primarily with axillary lymph nodes metastasis. The patient's axillary lymph node was biopsied and revealed a Grade III neuroendocrine tumor. A positron emission tomography (PET) scan was done in searching of a primary lesion and showed a highly metabolic mass of the left tonsil as well as a left axillary lymph node suggestive of metastasis. The patient has been managed with a multimodality approach, with a combination of chemotherapy regimen and surgical resection of the axillary lymph node. Subsequent PET scan evaluation showed a complete response of the primary tumor with residual left axillary lymph node metastasis. NECs of tonsil presented with axillary lymph nodes metastasis is rare and has a poor prognostic outcome. It poses a dilemma with regard to management, as surgical resection of the metastasis is not promising given the possibility of early recurrence.

A Comprehensive Review on Neuroendocrine Neoplasms: Presentation, Pathophysiology and Management

Neuroendocrine neoplasms (NENs) are a group of heterogeneous tumors with neuroendocrine differentiation that can arise from any organ. They account for 2% of all malignancies in the United States. A significant proportion of NEN patients experience endocrine imbalances consequent to increased amine or peptide hormone secretion, impacting their quality of life and prognosis. Over the last decade, pathologic categorization, diagnostic techniques and therapeutic choices for NENs-both well-differentiated neuroendocrine tumors (NETs) and poorly differentiated neuroendocrine carcinomas (NECs)-have appreciably evolved. Diagnosis of NEN mostly follows a suspicion from clinical features or incidental imaging findings. Hormonal or non-hormonal biomarkers (like serum serotonin, urine 5-HIAA, gastrin and VIP) and histology of a suspected NEN is, therefore, critical for both confirmation of the diagnosis and classification as an NET or NEC. Therapy for NENs has progressed recently based on a better molecular understanding, including the involvement of mTOR, VEGF and peptide receptor radionuclide therapy (PRRT), which add to the growing evidence supporting the possibility of treatment beyond complete resection. As the incidence of NENs is on the rise in the United States and several other countries, physicians are more likely to see these cases, and their better understanding may support earlier diagnosis and tailoring treatment to the patient. We have compiled clinically significant evidence for NENs, including relevant changes to clinical practice that have greatly updated our diagnostic and therapeutic approach for NEN patients.

Surgical aspects of small intestinal neuroendocrine tumors

Small intestinal neuroendocrine tumors (NETs) are a heterogeneous group of epithelial tumors with a predominant neuroendocrine differentiation. Although NETs are usually considered rare neoplasms, small intestinal NETs are the most common primary malignancy of the small bowel, with an increasing prevalence worldwide during the course of the past few decades. The indolent nature of these tumors often leads to a delayed diagnosis, resulting in over one-third of patients presenting with synchronous metastases. Primary tumor resection remains the only curative option for this type of tumor. In this review article, the various surgical aspects for the excision of small intestinal NETs are discussed.

Diagnostic Challenge of Small Bowel Neuroendocrine Tumor in a Young Female Patient

Neuroendocrine tumors (NETs) are rare cancers arising from neuroendocrine cells and are characterized by their ability to secrete functional hormones causing distinctive hormonal syndromes. The incidence of NET has increased over the years, and small bowel neuroendocrine tumor (SBNET) is one of the most challenging to detect due to its varied presentation and poor accessibility with traditional endoscopic methods. Patients with SBNET present with variable hormonal symptoms, such as diarrhea, flushing, and nonspecific abdominal pain, which often delay the diagnosis. We present the case of a young patient who underwent multidisciplinary workups leading to a successful diagnosis of SBNET promptly. The patient was a 31-year-old female who presented to the emergency department with complaints of nausea, vomiting, and sudden-onset, severe, sharp abdominal pain. CT scan of her abdomen showed an area of irregular intraluminal soft tissue density suspicious for a mass in the mid-small bowel. The patient's initial enteroscopy was normal. A video capsule endoscopy showed a small bowel mass, which was consistent with SBNET confirmed by pathology later. This case emphasizes the importance of considering SBNET as a differential diagnosis in young patients with nonspecific symptoms of abdominal pain and highlights the role of multidisciplinary approaches in achieving prompt diagnosis and treatment.

Pediatric Neuroendocrine Neoplasms: Rare Malignancies with Incredible Variability

Neuroendocrine neoplasms (NENs) encompass a variety of neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs) which can arise anywhere in the body. While relatively rare in the pediatric population, the incidence of NENs has increased in the past few decades. These neoplasms can be devastating if not diagnosed and treated early, however, symptoms are variable and can be indolent for many years. There is a reported median of 10 years from the appearance of the first symptoms to time of diagnosis. Considering some of these neoplasms have a mortality rate as high as 90%, it is crucial healthcare providers are aware of NENs and remain vigilant. With better provider education and easily accessible resources for information about these neoplasms, awareness can be improved leading to earlier disease recognition and diagnosis. This manuscript aims to provide an overview of both the most common NENs as well as the rarer NENs with high lethality in the pediatric population. This review provides up to date evidence and recommendations, encompassing recent changes in classification and advances in treatment modalities, including recently completed and ongoing clinical trials.

Neutrophil to lymphocyte ratio as a prognosis biomarker of PRRT in NET patients

PURPOSE

Peptide Receptor Radionuclide Therapy (PRRT) with 177Lu-DOTATATE is a palliative therapeutic option for advanced Neuroendocrine Tumors (NETs). Prognostic factors can predict long-term outcomes and determine response to therapy. Among those already explored, biomarkers from full blood count, including neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) has shown value for other solid tumors and for NETs patients submitted to other forms of therapy. However, its relation to PRRT response and patients' prognosis is still to be determined.

METHODS

Medical records from 96 patients submitted to PRRT between 2010 and 2017 were reviewed, median NLR and PLR were calculated from baseline flood blood count and dichotomized as high or low. Progression-free survival (PFS) and Overall Survival (OS) were calculated.

RESULTS

NLR and PLR median values were 1.8 and 123, respectively. Patients with low NLR had a significantly longer OS (estimated median of 77.5 months, 95% CI: 27.3-127.7) when compared to patients with high NLR (estimated median of 47.7 months, 95% CI: 34.7-60.8); p = 0.04. Patients with low NLR had a trend toward a longer median PFS when compared to patients with high NLR [estimated medians of 77 months (95% CI: 27.3-127.7), and 47.7 months, (95% CI: 34.7-60.7)], respectively, p = 0.08.

CONCLUSION

Patients with advanced-stage NET with NLR higher than 1.8 have worse long term clinical outcomes after PPRT. Larger studies are needed to validate the optimal cutoff for this biomarker.

The clinical and prognostic factors for biliary neuroendocrine neoplasm: a study based on the SEER database

Background

In this study, we aimed at elucidating the postoperative survival and prognostic factors in patients with biliary neuroendocrine neoplasm (NEN).

Methods

Cases of biliary system NEN and adenocarcinoma from 1975 to 2016 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. A propensity score matching (PSM) method was used to adjust baseline differences in clinicopathological characteristics in our analysis. The Kaplan–Meier analysis was carried out for survival analysis.

Results

A total of 233 patients with biliary system NEN were enrolled in this study, of which 119 patients’ lesions located in gallbladder, while the others’ located in bile duct. The postoperative overall survival of bile duct NEN is significantly longer than that of gallbladder NEN (P < 0.001). For gallbladder NENs, surgery method (P = 0.020) and lymph node metastasis (P = 0.018) were identified as independent prognostic factors. In terms of ampulla of vater (AOV) NENs, age (P = 0.017) and lymph node metastasis (P = 0.006) were identified as independent prognostic factors, while grade (P = 0.002) and lymph node metastasis (P = 0.036) were identified as independent prognostic factors for extrahepatic bile duct (EBD) NENs. PSM analysis indicated that patients with biliary duct NENs have a better postoperative prognosis than biliary duct adenocarcinoma.

Conclusions

Patients with NEN have better overall survival than patients with adenocarcinoma. Gallbladder NEN has an adverse prognosis than that of biliary tract NEN. The pathological subtype, differentiation, lymph node metastasis, surgery method, and lymph node resection could affect the postoperative prognosis of the gallbladder and biliary tract NEN.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-022-01689-7.

Laboratory variables as predictors of progression in gastroenteropancreatic neuroendocrine tumors in different lines of antineoplastic treatments

Objective:

To determine the association of red cell blood counts, and liver panel tests to predict outcomes in patients with gastroenteropancreatic neuroendocrine tumors who underwent systemic antineoplastic treatments.

Methods:

Patients with gastroenteropancreatic neuroendocrine tumors in systemic treatment were assessed according to laboratory tests within the same period. Progression free survival was determined by the period between the beginning of treatment and the date of progression. We used conditional models (PWP model) to verify the association between laboratory tests and tumor progression. The level of significance used was 5%.

Results:

A total of 30 treatments given to 17 patients in the intention-to-treat population were evaluated. Treatment included octreotide, lanreotide, everolimus, lutetium, and chemotherapy. We had statistically significant results in chromogranin A, neutrophils and platelets-to-lymphocyte ratio. The risk of progression increases by 2% with the addition of 100ng/mL of chromogranin A (p=0.034), 4% with the increase of 100 neutrophil units (p=0.006), and 21% with the addition of 10 units in platelets-to-lymphocyte ratio (p=0.002).

Conclusion:

Chromogranin A, neutrophils and platelets-to-lymphocyte ratio were associated with disease progression during systemic treatment in gastroenteropancreatic neuroendocrine tumors. Further prospective studies with larger cohorts are necessary to validate our findings.

Childhood neuroendocrine tumors of the digestive system: A single center experience

The prevalence and incidence of neuroendocrine tumors (NETs) are increasing in the pediatric population. This increase can be associated with improved diagnostics and increased detection rates of the disease. We aimed to discuss the clinical and pathological characteristics of patients with this rare disease who were followed and treated at our center.The medical records of children (aged 0-18 years) with NETs of the digestive system, followed up and treated between 2007 and 2020 at Ondokuz Mayis University Faculty of Medicine, were reviewed.Overall, 16 patients (8 girls and 8 boys) were analyzed. Fifteen patients had NETs in the appendix; 14 of these had grade I NETs, and 1 had grade II NETs. No additional surgery was performed except for appendectomy. All patients were in complete remission at the last follow-up (median 38 months). The other patient, a 12-year-old girl, had a primary hepatic neuroendocrine carcinoma (grade III NET). Three cycles of neoadjuvant and adjuvant platinum-based chemotherapy were administered, and right hepatectomy was performed to remove the mass. The patient is being followed-up for approximately 3 years without disease recurrence.Most NETs are observed in adults, and most studies have focused on this population. Unlike adults, increasing awareness of the disease in the pediatric population (especially in cases of acute appendicitis), discovering therapeutic treatments, and sharing experiences are crucial for developing an optimal therapeutic approach for pediatric NETs.

Gastric neuroendocrine neoplasms and precursor lesions: Case reports and literature review

RATIONALE

Gastric neuroendocrine neoplasms (g-NENs) represent a distinctive group of gastric tumors, stratified into different prognostic categories according to different histological characteristics, put forth in the 2018 World Health Organization classification system. The clinical presentations, as well as pathological features, represent important data in establishing the type of the tumor, in estimating the tumor behavior, and in selecting the best therapeutic strategy. In our case series we presented different clinical scenarios that may be encountered in practice regarding gastric NENs. We performed a literature review and discussed diagnostic strategy, current classification system, precursor lesions, and therapeutic options in g-NENs.

PATIENT CONCERNS

The first patient was a 41-year-old female with weight loss, persistent dyspeptic complaints and a history of pernicious anemia. In the second clinical case a 61-year-old man was admitted with heartburn, abdominal pain, diarrhea and mild iron deficiency anemia. The third patient was a 56-year-old male with a history of neoplasia, admitted for weight loss, dyspeptic complaints, and liver metastases.

DIAGNOSIS

All the 3 patients underwent upper endoscopy with targeted biopsies. Histopathological and laboratory evaluation, together with imagistic evaluation (abdominal ultrasound, endoscopic ultrasound, and magnetic resonance imaging) allowed the distinction between 3 different types of gastric tumors: type 1 enterochromaffin-like-cell G1 NET, type 2 enterochromaffin-like-cell G2 NET, and type 3 G2 NET with liver metastases.

INTERVENTIONS

Endoscopic polypectomy of the largest lesion was performed in patient with type 1 g-NET and autoimmune chronic atrophic gastritis, followed by regular endoscopic surveillance with biopsies. In type 2 g-NET associated with pancreatic gastrinoma, pancreaticoduodenectomy with total gastrectomy were performed. In type 3 g-NET, detected in metastatic stage, oncologic therapy was performed.

OUTCOMES

The patients follow-up was selected according to tumor behavior, from regular endoscopic surveillance to oncology follow-up. The prognosis was good in case 1, whilst poorer outcomes were associated with more aggressive tumors in case 2 and case 3.

LESSONS

g-NENs are rare tumors with distinct clinical and histological features. Our case series emphasized the role of close collaboration between clinician and pathologist, as well as the importance of a detailed pathology report.

The new WHO classification of gastrointestinal neuroendocrine tumors and immunohistochemical expression of somatostatin receptor 2 and 5

The 2019 World Health Organization (WHO) classification of gastrointestinal tumors defines well-differentiated grade 3 neuroendocrine tumors, the mixed neuroendocrine-non-neuroendocrine tumors (MiNENs) and classifies goblet cell carcinoid as goblet cell adenocarcinoma. The expression of somatostatin receptors (SSTRs) is the foundation for somatostatin analogue therapy. At present, there are only a few studies that have analyzed the immunohistochemical reactivity of SSTRs in gastrointestinal neuroendocrine neoplasms (NENs). The aim of the present study was to evaluate the immunohistochemical expression of SSTR2 and SSTR5 in gastrointestinal NENs and goblet cell adenocarcinomas and the correlation of these markers with clinical and morphological factors. The study included 67 patients with NENs and 4 patients with adenocarcinoma ex-goblet cell carcinoid diagnosed between January 2008 and December 2018. Tumors were reclassified according to the 2019 WHO classification. Immunohistochemical staining for chromogranin A, synaptophysin, Ki-67, p53, SSTR2, and SSTR5 were performed in all the cases. The results showed that, G1 and G2 neuroendocrine tumors were more common SSTR2-positive in comparison with G3 carcinomas (P<0.0001). In addition, 33.3% of neuroendocrine carcinomas and 2 cases of low-grade adenocarcinoma ex-goblet cell carcinoid were SSTR2-positive. Neuroendocrine carcinomas had significantly lower SSTR2 and SSTR5 expression compared with well-differentiated neuroendocrine tumors (P=0.0130; P=0.0437, respectively). The SSTR2 expression in the early tumor stages was 100%, more often than in advanced stages (55.6%; P=0.0011). The results demonstrated the decrease in SSTR2 expression with increasing malignancy and tumor stage. The SSTR2-positive expression in neuroendocrine carcinomas and adenocarcinoma ex-goblet cell carcinoid provides evidence for the benefits of somatostatin analog treatment associated with surgery and chemotherapy.

Management of Small Bowel Neuroendocrine Tumors

Small bowel neuroendocrine tumors (SBNETS) are slow-growing neoplasms with a noted propensity toward metastasis and comparatively favorable prognosis. The presentation of SBNETs is varied, although abdominal pain and obstructive symptoms are the most common presenting symptoms. In patients with metastases, hypersecretion of serotonin and other bioactive amines results in diarrhea, flushing, valvular heart disease, and bronchospasm, termed carcinoid syndrome. The treatment of SBNETs is multimodal and includes surgery, liver-directed therapy, somatostatin analogues, targeted therapy, and peptide receptor radionuclide therapy.

Flushing: A Diagnostic Dilemma

Carcinoid tumors are uncommon tumors that are often diagnosed in later stages of the disease due to their indolent nature, vague clinical presentation and overlap of symptoms with other conditions. We report a case of rectosigmoid carcinoid tumor which was found incidentally on screening colonoscopy in an elderly woman that went undiagnosed for several years due to confounding effects of symptoms of post-hysterectomy menopause with that of carcinoid syndrome. Persistent episodic flushing with or without diarrhea not resolved with standard treatment should lead to suspicion of neuroendocrine tumors (NETs). This case report emphasizes the need to broaden our perspective of menopausal symptoms and pay attention to the characteristic clinical symptoms of NETs.

Pediatric Gastrointestinal Stromal Tumors and Neuroendocrine Tumors: Advances in Surgical Management

Gastrointestinal stromal tumors and neuroendocrine tumors in adult and pediatric populations differ immensely. Despite these established differences, the extreme rarity of gastrointestinal stromal tumors and neuroendocrine tumors in the pediatric population has resulted in the lack of consensus management guidelines, making optimal surgical approaches unclear. Comprehensive management principles to guide surgical approaches in adult literature are extensive. However, these are still lacking for pediatric patients. International cooperation to develop standardized pediatric-specific guidelines is urgently warranted in the future. This article highlights the vast differences between adult and pediatric parameters and provides recommendations on optimal and novel surgical approaches in children.

A review of pediatric neuroendocrine tumors, their detection, and treatment by radioisotopes

Neuroendocrine tumors (NETs) are rare in childhood. Neuroblastoma is the most common pediatric extracranial solid tumor, occurring >90% in children younger than 5 years of age. Pheochromocytoma and paraganglioma are rare NETs, causing hypertension in 0.5-2% of hypertensive children. Gastroenteropancreatic NETs can occur in children and are classified into carcinoids and pancreatic tumors. Nuclear medicine procedures have an essential role both in the diagnosis and treatment of NETs. Metaiodobenzylguanidine (MIBG) labeled with radioiodine has a well-established role in diagnosis as well as therapeutic management of the neuroblastoma group of diseases. During recent decades, establishing the abundant expression of somatostatin receptors by NETs first led to scintigraphy with somatostatin analogs (i.e. Tc/In-octreotide) and, later, with the emergence of positron-emitting labeled agents (i.e. Ga-DOTATATE/DOTATOC/DOTANOC) PET scans with significantly higher detection efficiency became available. Therapy with somatostatin analogs labeled with beta emitters such as Lu-177 and Y-90, known as peptide receptor radionuclide therapy, is a promising new option in the management of patients with inoperable or metastasized NETs. In this article, pediatric NETs are briefly reviewed and the role of radioactive agents in the detection and treatment of these tumors is discussed.

Surgical Management of Neuroendocrine Tumor Liver Metastases

Patients with neuroendocrine tumor liver metastases (NETLMs) may develop carcinoid syndrome, carcinoid heart disease, or other symptoms from overproduction of hormones. Hepatic resection and cytoreduction is the most direct treatment of NETLMs in eligible patients, and cytoreduction improves symptoms, may reduce the sequelae of carcinoid syndrome, and extends survival. Parenchymal-sparing procedures, such as ablation and enucleation, should be considered during cytoreduction to maximize treatment of multifocal tumors while preserving healthy liver tissue. For patients with large hepatic tumor burdens, high-grade disease, or comorbidities precluding surgery, liver-directed and systemic therapies can be used to palliate symptoms and improve progression-free survival.

Differential diagnosis of diarrhoea in patients with neuroendocrine tumours: A systematic review

BACKGROUND

Approximately 20% of patients with neuroendocrine tumours (NETs) develop carcinoid syndrome (CS), characterised by flushing and diarrhoea. Somatostatin analogues or telotristat can be used to control symptoms of CS through inhibition of serotonin secretion. Although CS is often the cause of diarrhoea among patients with gastroenteropancreatic NETs (GEP-NETs), other causes to consider include pancreatic enzyme insufficiency (PEI), bile acid malabsorption and small intestinal bacterial overgrowth. If other causes of diarrhoea unrelated to serotonin secretion are mistaken for CS diarrhoea, these treatments may be ineffective against the diarrhoea, risking detrimental effects to patient quality of life.

AIM

To identify and synthesise qualitative and quantitative evidence relating to the differential diagnosis of diarrhoea in patients with GEP-NETs.

METHODS

Electronic databases (MEDLINE, Embase and the Cochrane Library) were searched from inception to September 12, 2018 using terms for NETs and diarrhoea. Congresses, systematic literature review bibliographies and included articles were also hand-searched. Any study designs and publication types were eligible for inclusion if relevant data on a cause(s) of diarrhoea in patients with GEP-NETs were reported. Studies were screened by two independent reviewers at abstract and full-text stages. Framework synthesis was adapted to synthesise quantitative and qualitative data. The definition of qualitative data was expanded to include all textual data in any section of relevant publications.

RESULTS

Forty-seven publications (44 studies) were included, comprising a variety of publication types, including observational studies, reviews, guidelines, case reports, interventional studies, and opinion pieces. Most reported on PEI on/after treatment with somatostatin analogs; 9.5%-84% of patients with GEP-NETs had experienced steatorrhoea or confirmed PEI. Where reported, 14.3%–50.7% of patients received pancreatic enzyme replacement therapy. Other causes of diarrhoea reported in patients with GEP-NETs included bile acid malabsorption (80%), small intestinal bacterial overgrowth (23.6%-62%), colitis (20%) and infection (7.1%). Diagnostic approaches included faecal elastase, breath tests, tauroselcholic (selenium-75) acid (SeHCAT) scan and stool culture, although evidence on the effectiveness or diagnostic accuracy of these approaches was limited. Assessment of patient history or diarrhoea characteristics was also reported as initial approaches for investigation. From the identified evidence, if diarrhoea is assumed to be CS diarrhoea, consequences include uncontrolled diarrhoea, malnutrition, and perceived ineffectiveness of CS treatment. Approaches for facilitating differential diagnosis of diarrhoea include improving patient and clinician awareness of non-CS causes and involvement of a multidisciplinary clinical team, including gastroenterologists.

CONCLUSION

Diarrhoea in GEP-NETs can be multifactorial with misdiagnosis leading to delayed patient recovery and inefficient resource use. This systematic literature review highlights gaps for further research on prevalence of non-CS diarrhoea and suitability of diagnostic approaches, to determine an effective algorithm for differential diagnosis of GEP-NET diarrhoea.

Refractory Paraneoplastic Diarrhea Secondary to Adenocarcinoma of the Lung: A Case Report and Literature Review

Paraneoplastic diarrhea is a commonly described complication of gastrointestinal tract or endocrine malignancies. It is an extremely rare complication of lung adenocarcinoma, with only one previously reported case in the literature. A 46-year-old female with newly diagnosed stage IVb lung adenocarcinoma presented to our intensive care unit in hypovolemic shock with symptoms suggestive of diabetes insipidus (DI) as well as profuse large volume watery diarrhea. Exhaustive serological and microbiological workup revealed the diarrhea to be paraneoplasitc in nature. This case represents the second known case of paraneoplastic diarrhea secondary to lung adenocarcinoma. Clinicians should be aware of this rare phenomenon.

An Update on Gastroenteropancreatic Neuroendocrine Neoplasms: From Mysteries to Paradigm Shifts

Although neuroendocrine neoplasms (NEN) were once thought to be rare and mostly "benign" diseases, they are now being redefined in light of recently discovered molecular information. NENs constitute a spectrum of variably differentiated neoplasms, ranging from well-differentiated tumors with a protracted course over many years to very aggressive neuroendocrine carcinomas. Although the majority of NEN are non-functional lesions, some of these tumors, do produce a hormonal hypersecretion syndrome. Their reappraisal has led scientist to unveil previously unknown oncogenic pathways and connections that resulted in a new category in the International Classification of Diseases (ICD-11) and a revised version of the World Health Organization Classification (WHO 2018). Complex diseases like NEN require a multidisciplinary approach that includes the perspectives of endocrinologists, medical and surgical oncologists, radiation oncologists, imaging specialists and pathologists. There are currently virtually thousands of ongoing trials evaluating the efficacy and safety of several molecular targeted therapies. The purpose of this review was to critically evaluate recent information regarding the pathogenesis, diagnosis and treatment of NEN.

French patient-reported experience of diagnosis, management and burden of neuroendocrine tumors

Background: There is a lack of knowledge regarding the experience of patients with neuroendocrine tumors (NET) in France. Materials & methods: A patient survey that captured information on diagnosis, disease impact/management and awareness was conducted. Data of respondents from France were analyzed and compared with US data as a reference. Results: Key topics included delays in diagnosis, negative impact on quality of life, patient access to NET medical experts and treatments, and information on NET and treatments. Significant differences were observed between France and the USA regarding NET diagnosis. Conclusion: This survey highlights the considerable burden experienced by patients in France with NET and differences in patient experience between France and the USA that may result from different healthcare and social systems.

Does the addition of adjuvant intraoperative tumor bed chemotherapy during midgut neuroendocrine tumor debulking procedures benefit patients?

Background

Midgut neuroendocrine tumor (NET) patients are often diagnosed at advanced stages with extensive mesenteric nodal and hepatic metastasis. The only potentially curative treatment is surgical tumor eradication. Despite an aggressive resection, macro and microscopic residual disease still may remain in the resection bed. We hypothesize that the application of 5-fluorouracil (5-FU) within the tumor bed will help eliminate microscopic residual disease.

Methods

Records of 189 patients who underwent extensive cytoreductive surgeries during 2003-2012 for advanced, midgut NETs with extensive mesenteric lymphadenopathy were reviewed. Eighty-six patients (46%) who had 5-FU saturated gel foam strips secured into their mesenteric resection sites served as the study group and a matching 103 patients (54%) who did not have such an intra-operative chemotherapy served as controls. Survival from the time of diagnosis and post-operative complications between the two groups were compared.

Results

Mortality rates at 30, 60 and 90 days post-operatively were 4%, 0%, 0% versus 2%, 0%, 2% for study and control groups, respectively. Major complications (Grades III & IV) at the same intervals were 0, 0, 1 versus 2, 3, 2 for study and control groups, respectively. Median survival was 236 months versus 148 months for the study and control groups, respectively 24 (P=0.15).

Conclusions

Intraoperative tumor resection bed chemotherapy is a safe adjuvant without discernible toxicity. This procedure may provide survival benefits to midgut NET patients with extensive mesenteric lymphadenopathy undergoing extensive cytoreductive surgery. Further study in prospective trials must be conducted to determine definitive benefit to the NET patient.

Evaluation and Management of Neuroendocrine Tumors of the Pancreas

Pancreatic neuroendocrine tumors are a diverse group of neoplasms with a generally favorable prognosis. Although they exhibit indolent growth, metastases are seen in roughly 60% of patients. Pancreatic neuroendocrine tumors may produce a wide variety of hormones, which are associated with dramatic symptoms, but the majority are nonfunctional. The diagnosis and treatment of these tumors is a multidisciplinary effort, and management guidelines continue to evolve. This review provides a concise summary of the presentation, diagnosis, surgical management, and systemic treatment of pancreatic neuroendocrine tumors.

Neuroendocrine Tumors in Pediatrics

Neuroendocrine cells are dispersed diffusely throughout many organ systems in the body and hence neuroendocrine tumors (NETs) can arise from almost anywhere in the body. NETs are considered rare tumors, and the current incidence is reported to be about 6 cases in 100 000 in adults and about 2.8 cases per million in the pediatric age group. Despite the indolent nature of these tumors, they have the potential for metastasis and significant morbidity. NETs can be asymptomatic at the time of diagnosis or can present with flushing, diarrhea, wheezing, weight loss, and fatigue among other symptoms. Due to the ambiguity of presenting symptoms, it is not uncommon for NETs to be diagnosed late in the disease course. Despite low incidence, the prevalence of the disease is high since patients live for many years and sometimes decades. Early detection of well-differentiated NETs has excellent outcomes with the majority of early-stage diseases being cured with surgical resection alone. There have been recent advancements in the management of metastatic progressive NETs with approval of peptide receptor radionuclide therapy, telotristat, and everolimus. Awareness of these rare tumors and its management is crucial for optimal management. This article will focus on pediatric NETs and current advances in its management.

Primary hepatic carcinoid tumor metastasizing to eyelid: A case report

Purpose

We report a rare case of a metastatic carcinoid tumor to the right lower lid masquerading as a chalazion.

Observations

A 78-year-old Hispanic woman who presented with a 3-month history of a non-resolving chalazion on the right lower lid despite aggressive medical treatment. The patient had a history of noninfectious anterior uveitis and primary hepatic carcinoid tumor that was incidentally diagnosed during the initial uveitis work-up. The right lower eyelid lesion was biopsied and histological and immunopathological analysis revealed a well differentiated neuroendocrine tumor consistent with a carcinoid tumor.

Conclusionand Importance

Neuroendocrine tumors should be considered as part of the differential diagnosis of focal, vascularized eyelid masses. To the authors best knowledge this is the first reported case of primary hepatic carcinoid tumor with metastasis to the eyelids. We also highlight the importance of pursuing a histopathologic diagnosis, in the setting of a non-resolving or recurrent chalazion.

LARGE CELL METASTATIC PANCREATIC NEUROENDOCRINE CARCINOMA TREATED WITH SOMATOSTATIN ANALOGUES - CASE REPORT AND LITERATURE REVIEW

We report the case of a 55-year-old-male with a large cell metastatic pancreatic neuroendocrine carcinoma treated for 14 months with lanreotide autogel having a stable disease (SD) and not responding to chemotherapy. The somatostatin analogues (SSA) were introduced after an episode of diarrhea and controlled the disease. Progression-free survival (PFS) as determined by Computerized Tomography (CT) scans was obtained for 14 months. After more than a year, the patient's health state deteriorated along with progressive disease. The capecitabine-temozolomide regimen was challenged, but after three cycles, a rapid clinical decline was noted.

CONCLUSION

This unexpected event (diarrhea) in the course of the disease could represent the beginning of carcinoid syndrome. While the lanreotide autogel helped the episode of diarrhea pass, it also helped gain control over the disease itself.

Neuroendocrine neoplasms of gastrointestinal tract and secondary primary synchronous tumors: A systematic review of case reports. Casualty or causality?

BACKGROUND

Neuroendocrine neoplasms (NENs) can arise in most of the epithelial organs of the body and are not a rare condition in the gastrointestinal tract (GIT). The presence of NENs in GIT associated with other secondary primary malignancies (SPM) has been considered an exotic event. This study aims to describe the case reports of NENs accompanied by synchronous primary tumors.

METHODS AND FINDINGS

We performed a systematic literature search of the databases Scopus, PubMed, Scielo and LILACS to identify case reports that described the presence of NENs in GIT with SPM. 78 case reports were included. The mean of age of the cases was 60.2 years. 60% were male. 95.4% were NENs G1. 17 cases of NENs had metastasis. 80% of SPM were recognized in the GIT (36% in stomach, 27% in large intestine, 11.2% in small intestine, and 5.6% in esophagus). The most common type of SPM was adenocarcinoma (49.4%), followed by GIST (13.5%), other NENs in different GIT segment (7.9%), lymphoma (6.8%), and squamous cell carcinoma (4.5%). The most common tumor in GIT was adenocarcinoma (97.6%) and the presence of adenocarcinoma in the same segment of GIT was found in 68.4% of the cases. Association between adenocarcinomas and NENs in GIT (p:<0.0001) and adenocarcinoma and tumor in the same segment of GIT location were observed (p<0.001).

CONCLUSION

These results demonstrate that NENs with SPM are not a rare condition. Several theories have been proposed to explain this association; one of these is the ability of NENs to generate synchronous tumors by autocrine and paracrine effect. We observed an association between adenocarcinomas and NENs in the same segment of GIT.

BIOCHEMICAL RESPONSES IN SYMPTOMATIC AND ASYMPTOMATIC PATIENTS WITH NEUROENDOCRINE TUMORS: POOLED ANALYSIS OF 2 PHASE 3 TRIALS

OBJECTIVE

Neuroendocrine tumors (NETs) are associated with elevated 5-hydroxyindoleacetic acid (5-HIAA) and chromogranin A (CgA) levels. This study aimed to analyze relationships between urinary 5-HIAA and plasma CgA levels and clinical outcomes.

METHODS

Centrally assessed biomarker levels and correlations with progression-free survival (PFS) and carcinoid syndrome (CS) symptom control were evaluated in a pooled analysis of CLARINET (96-week randomized, double-blind, placebo-controlled) and ELECT (16-week randomized, double-blind, placebo-controlled, 32-week initial open label and ≥2 year long-term extension open label) studies of adults with NETs, with (ELECT) or without (CLARINET) CS at 97 institutions. Patients were treated with subcutaneous lanreotide depot 120 mg monthly.

RESULTS

Of 319 pooled patients, 86% and 95% had baseline 5-HIAA and CgA data, respectively, with 47% and 74% having levels greater than the upper limit of normal (ULN). PFS was longer among patients who experienced a decrease in biomarker levels at week 12, with statistical significance reached in the CgA cohort (not reached vs. 14.4 months; P<.0001). A large proportion (87%) of patients without symptoms of CS in the CLARINET study had detectable levels of 5-HIAA (48% >ULN). In ELECT, patients with CS who received lanreotide and experienced a biochemical response (≥50% decrease from baseline) achieved greater symptom control.

CONCLUSION

This pooled analysis of two randomized, placebo-controlled trials demonstrated that 5-HIAA and CgA are secreted as biochemical biomarkers in many patients with NETs, regardless of clinical syndromes. Significant biochemical response was associated with improved clinical outcomes, as measured by improved PFS or improved CS symptom control.

ABBREVIATIONS

5-HIAA = 5-hydroxyindoleacetic acid; CgA = chromogranin A; CI = confidence interval; CLARINET = Controlled Study of Lanreotide Antiproliferative Response in Neuroendocrine Tumors; CS = carcinoid syndrome; ELECT = Evaluation of Lanreotide Depot/Autogel Efficacy and Safety as a Carcinoid Syndrome Treatment; HR = hazard ratio; ITT = intention-to-treat; NET = neuroendocrine tumor; PanNET = pancreatic NET; PFS = progression-free survival; PPI = proton pump inhibitor; SSA = somatostatin analogue; ULN = upper limit of normal.

Management of Small Bowel Neuroendocrine Tumors

Small bowel neuroendocrine tumors (NETs) are increasing in incidence and are now the most common primary malignancies of the small intestine. Despite this increase, the vague presentation and slow growth of these tumors lead to long delays in diagnosis, and many patients present with metastases. Patients with metastatic small bowel NETs have a favorable disease prognosis, particularly when contrasted with other GI malignancies, and benefit from aggressive, multimodal therapy. During the past decade, the options for the diagnosis and treatment of small bowel NETs have increased considerably. This review provides a practical framework for the physician who seek to understand the epidemiology, presentation, diagnosis, and management of small bowel NETs.

Two Cases of Primary Hepatic Neuroendocrine Tumors and a Review of the Current Literature

Neuroendocrine tumors comprise approximately 1-2% of all gastrointestinal tumors, and while the liver is the most common site for metastasis of these tumors, primary hepatic neuroendocrine tumors are very rare entities. Since first being reported in 1958, there have been less than 150 cases reported in the literature. Because of the infrequent occurrence of these tumors, the pool of data available for analysis regarding these tumors is small. As such, the medical community must rely on the publication of case report data to further enlarge this data pool, with the hopes of eventually having enough data to draw meaningful, statistically significant conclusions with regard to diagnosis and management of these rare tumors. We have encountered two patients at our institution within the last year with primary hepatic neuroendocrine tumors. We present their cases in this manuscript in an effort to contribute to the available data on the disease. We also provide a concise review of the literature available to date regarding primary hepatic neuroendocrine tumors.

Development of a Framework Based on Reflective MCDA to Support Patient-Clinician Shared Decision-Making: The Case of the Management of Gastroenteropancreatic Neuroendocrine Tumors (GEP-NET) in the United States

Introduction

Well- or moderately differentiated gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are often slow-growing, and some patients with unresectable, asymptomatic, non-functioning tumors may face the choice between watchful waiting (WW), or somatostatin analogues (SSA) to delay progression. We developed a comprehensive multi-criteria decision analysis (MCDA) framework to help patients and physicians clarify their values and preferences, consider each decision criterion, and support communication and shared decision-making.

Methods

The framework was adapted from a generic MCDA framework (EVIDEM) with patient and clinician input. During a workshop, patients and clinicians expressed their individual values and preferences (criteria weights) and, on the basis of two scenarios (treatment vs WW; SSA-1 [lanreotide] vs SSA-2 [octreotide]) with evidence from a literature review, expressed how consideration of each criterion would impact their decision in favor of either option (score), and shared their knowledge and insights verbally and in writing.

Results

The framework included benefit-risk criteria and modulating factors, such as disease severity, quality of evidence, costs, and constraints. Overall and progression-free survival being most important, criteria weights ranged widely, highlighting variations in individual values and the need to share them. Scoring and considering each criterion prompted a rich exchange of perspectives and uncovered individual assumptions and interpretations. At the group level, type of benefit, disease severity, effectiveness, and quality of evidence favored treatment; cost aspects favored WW (scenario 1). For scenario 2, most criteria did not favor either option.

Conclusions

Patients and clinicians consider many aspects in decision-making. The MCDA framework provided a common interpretive frame to structure this complexity, support individual reflection, and share perspectives.

Funding

Ipsen Pharma.

Electronic supplementary material

The online version of this article (10.1007/s12325-017-0653-1) contains supplementary material, which is available to authorized users.

Neurotensin Receptor 3/Sortilin Contributes to Tumorigenesis of Neuroendocrine Tumors Through Augmentation of Cell Adhesion and Migration

Neurotensin (NTS), a 13–amino acid peptide which is distributed predominantly along gastrointestinal tract, has multiple physiologic and pathologic functions, and its effects are mediated by three distinct NTS receptors (NTSRs). Overexpression and activation of NTS signaling components, especially NTS and/or NTSR1, are closely linked with cancer progression and metastasis in various types of cancers including neuroendocrine tumors (NETs). Although deregulation of NTSR3/sortilin has been implicated in a variety of human diseases, the expression and role of NTSR3/sortilin in NETs have not been elucidated. In this study, we investigated the expression and oncogenic effect of NTSR3/sortilin in NETs. Increased protein levels of NTSR3/sortilin were noted in the majority of human clinical NETs (n = 21) by immunohistochemical analyses compared with normal tissues (n = 12). Expression of NTS and NTSR3/sortilin was also noted in all tested NET cell lines. In addition, small interfering RNA–mediated knockdown of NTSR3/sortilin decreased cell number without alteration of cell cycle progression and apoptosis induction in NET cell lines BON and QGP-1. Moreover, silencing of NTSR3/sortilin significantly suppressed cell adhesion and cell migration with inhibition of focal adhesion kinase and Src phosphorylation in the NET cells. Our results demonstrate increased expression of NTSR3/sortilin in NET patient tissues and a critical role of NTSR3/sortilin on NET cell adhesion and migration suggesting that NTSR3/sortilin contributes to NET tumorigenesis.

Nothing But NET: A Review of Neuroendocrine Tumors and Carcinomas

This review covers the diverse topic of neuroendocrine neoplasms (NENs), a relatively rare and heterogeneous tumor type, comprising ~2% of all malignancies, with a prevalence of <200,000 in the United States, which makes it an orphan disease (Basu et al., 2010).1 For functional purposes, NENs are divided into two groups on the basis of clinical behavior, histology, and proliferation rate: well differentiated (low grade to intermediate grade) neuroendocrine tumors and poorly differentiated (high grade) neuroendocrine carcinoma (Bosman et al., 2010)2; this histological categorization/dichotomization is highly clinically relevant with respect to impact on treatment and prognosis even though it is not absolute since a subset of tumors with a low-grade appearance behaves similarly to high-grade lesions. Given the relative dearth of evidenced-based literature about this orphan disease as a whole (Modlin et al., 2008),3 since the focus of most articles is on particular anatomic subtypes of NENs (i.e., gastroenteropancreatic or pulmonary), the purpose of this review is to summarize the presentation, pathophysiology, staging, current standard of care treatments, and active areas of current research.

Tumor microenvironment of gastroenteropancreatic neuroendocrine neoplasms

Tumor microenvironment provides a unique environment for tumor development, where the biology behavior of tumor cells is regulated not only by their genetics but also by the surrounding environment. Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) originating from the neuroendocrine cells of the gastroenteropancreatic system are characterized by a propensity to secrete a variety of peptide hormones and biogenic amines. The symptoms of GEP-NENs at early stages are often atypical, thus delaying the diagnosis. A further understanding of the pathobiology of GEP-NENs on the basis of studies on GEP-NENs tumor microenvironment can provide new evidence for clinical diagnosis and treatment. This review aims to introduce different cell types, several proteins involved in extracellular matrix remodeling, some growth factors, and chromogranin A (CgA) in the tumor microenvironment of GEP-NENs, in order to highlight their indispensable roles in GEP-NENs progression.

Patient-Reported Symptom Control of Diarrhea and Flushing in Patients with Neuroendocrine Tumors Treated with Lanreotide Depot/Autogel: Results from a Randomized, Placebo-Controlled, Double-Blind and 32-Week Open-Label Study

BACKGROUND

In the double-blind (DB) ELECT study, lanreotide depot/autogel significantly reduced versus placebo the need for short-acting octreotide for symptomatic carcinoid syndrome (CS) control in neuroendocrine tumor (NET) patients. Here we present patient-reported symptom data during DB and initial open-label (IOL) treatment.

MATERIALS AND METHODS

Adults with NETs and CS history, with/without prior somatostatin analog use, were randomized to 16 weeks' DB lanreotide 120 mg subcutaneous or placebo every 4 weeks, followed by 32 weeks' IOL lanreotide. Patients recorded diarrhea and/or flushing frequency and severity daily by Interactive Voice (Web) Response System for 1 month prior to randomization and throughout the study.

RESULTS

Of 115 patients randomized (n = 59 lanreotide, n = 56 placebo), 56 lanreotide and 45 placebo patients enrolled in the IOL phase. During DB treatment, least square (LS) mean percentages of days with moderate/severe diarrhea and/or flushing were significantly lower for lanreotide (23.4%) versus placebo (35.8%; LS mean difference [95% confidence interval]: -12.4 [-20.73 to -4.07]; p = .004). For DB lanreotide patients, average daily composite (frequency × severity) diarrhea scores improved significantly between DB and IOL treatment (mean difference: -0.71 [-1.20 to -0.22]; p = .005), and remained stable for diarrhea and/or flushing. For DB placebo patients, composite scores for diarrhea, flushing, and diarrhea and/or flushing improved significantly between DB and IOL treatment (mean differences: -1.07 [-1.65 to -0.49]; -1.06 [-1.93 to -0.19]; and -2.13 [-3.35 to -0.91]; all p ≤ .018).

CONCLUSION

Improved diarrhea and flushing control in CS patients during 16-week lanreotide treatment was sustained during maintenance of lanreotide treatment for the 32-week IOL phase (48 weeks total).

IMPLICATIONS FOR PRACTICE

This study prospectively collected daily patient-reported data on diarrhea and flushing from the ELECT trial to evaluate the direct impact of lanreotide depot on patients' relief of carcinoid syndrome symptoms. Treatment with lanreotide depot was associated with significant reductions in the percentages of days patients reported symptoms of diarrhea and flushing, as well as reductions in the frequency and severity of daily symptoms compared with placebo during 16 weeks of double-blind treatment. These improvements were sustained for 32 additional weeks of open-label lanreotide treatment (i.e., through week 48 of treatment), resulting in clinically meaningful, long-term symptom reduction.

Evolving role of the endoscopist in management of gastrointestinal neuroendocrine tumors

Neuroendocrine tumors (NETs) are uncommon gastrointestinal neoplasms but have been increasingly recognized over the past few decades. Luminal NETs originate from the submucosa of the gastrointestinal tract and careful endoscopic exam is a key for accurate diagnosis. Despite their reputation as indolent tumors with a good prognosis, some NETs may have aggressive features with associated poor long-term survival. Management of NETs requires full understanding of tumor size, depth of invasion, local lymphadenopathy status, and location within the gastrointestinal tract. Staging with endoscopic ultrasound or cross-sectional imaging is important for determining whether endoscopic treatment is feasible. In general, small superficial NETs can be managed by endoscopic mucosal resection and endoscopic submucosal dissection (ESD). In contrast, NETs larger than 2 cm are almost universally treated with surgical resection with lymphadenectomy. For those tumors between 11-20 mm in size, careful evaluation can identify which NETs may be managed with endoscopic resection. The increasing adoption of ESD may improve the results of endoscopic resection for luminal NETs. However, enthusiasm for endoscopic resection must be tempered with respect for the more definitive curative results afforded by surgical treatment with more advanced lesions.

Progress in the treatment of esophageal neuroendocrine carcinoma

Esophageal neuroendocrine neoplasms are rare. With the improvement and popularization of diagnostic methods, the morbidity statistics have increased annually in recent years. There are currently no treatment guidelines for esophageal neuroendocrine neoplasms, and surgery is the only cure. This usually involves radical surgery when the tumor is limited to the primary site or when only regional lymph node metastasis occurs. Surgical treatment is key to treating esophageal neuroendocrine neoplasms, but combined treatment with chemotherapy and radiotherapy can significantly improve patient survival. The effect of radiotherapy alone on this disease is poor. However, targeted endocrine therapy can improve endocrine hormone symptoms. The prognosis of patients with esophageal neuroendocrine neoplasms is mainly determined by the pathological stage. With the development of molecular biology techniques, the combination of targeted drugs and traditional chemotherapy is expected to provide novel ideas and directions for the treatment of esophageal neuroendocrine neoplasms in the coming years. In this article, the status of esophageal neuroendocrine tumor treatments was reviewed in detail.

Co-expression of Achaete-Scute Homologue-1 and Calcitonin Gene-Related Peptide during NNK-Induced Pulmonary Neuroendocrine Hyperplasia and Carcinogenesis in Hamsters

Achaete-scute homologue-1 or ASCL1 (MASH1, hASH1) plays roles in neural development and pulmonary neuroendocrine (NE) differentiation, and it is expressed in certain lung cancers. This study was aimed to assess whether and/or how ASCL1 plays a role in 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced pulmonary NE hyperplasia and carcinogenesis in hamsters. Hamsters were injected 3 times weekly with either NNK or solvent alone (control) for treatment periods of 6 and 24 weeks, both without and with 6-week recovery. Immunohistochemical analysis was carried out to examine the expressions of ASCL1, CGRP (calcitonin gene-related peptide), secretoglobin SCGB1A1 (club [Clara] cell specific 10 kD protein, CC10, CCSP), synaptophysin (SYP), and PCNA (proliferating cell nuclear antigen). The number of ASCL1-expressing NE foci per airway increased from 0.8 in controls to 1.6 and 2.0 during NNK exposure for 6 and 24 weeks, respectively, and the number of cells per foci doubled after NNK exposure. Most ASCL1-expressing cells in NEBs (neuroepithelial bodies) were also CGRP immunoreactive; NNK enhanced this co-expression with CGRP, a NE marker with known proliferation-promoting properties. NNK also increased PCNA expression within NE foci. NNK-induced tumors showed no immunoreactivity for NE markers. This study confirms ASCL1 as an excellent marker for pulmonary NE cells and demonstrates CGRP co-expression in ASCL1-positive NEB cells participating in NNK-induced NE hyperplasia.

Current progress in diagnosis and therapy of neuroendocrine neoplasms of the digestive system

Neuroendocrine neoplasms (NENs) are a group of heterogeneous, biologically diverse, rare malignancies originated from the peptidergic neurons and neuroendocrine cells. In recent years, the incidence of NENs has been increasing gradually. They typically arise in the pancreas and gastrointestinal tract. Chromogranin A (CgA) has long been used as an important broad-spectrum marker for the identification of NENs. The diagnosis is based on histopathology demonstrating neuroendocrine features such as positive staining for chromogranin A and specific hormones such as gastrin, proinsulin, vasoactive intestinal peptide (VIP) and glucagon. In addition, radiological modalities including computed tomography (CT), positron emission tomography and computed tomography (PET/CT), magnetic resonance imaging (MRI), ultrasound (US), endoscopic ultrasound (EUS), and somatostatin receptor scintigraphy (SRS) can help establish a diagnosis. Surgery is still one of the cornerstones in the management of NENs. This article reviews the current progress in the diagnosis and therapy of NENs of the digestive system, including the pathological features and clinical diagnostic modalities for primary esophageal, gastric, duodenal, small intestinal, appendiceal, colonic, rectal, hepatic, gallbladder, extrahepatic bile duct, and pancreatic NENs, according to a revised system of classification, nomenclature and grading of NENs proposed by the fourth edition of "World Health Organization (WHO) classification of tumours of the digestive system" in 2010, and consensus of diagnosis and treatment of gastroenteropancreatic NENs (GEP-NENs) proposed by the Chinese Society of Clinical Oncology (CSCO) in 2013.

EVALUATION OF LANREOTIDE DEPOT/AUTOGEL EFFICACY AND SAFETY AS A CARCINOID SYNDROME TREATMENT (ELECT): A RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED TRIAL

OBJECTIVE

To evaluate the efficacy and safety of lanreotide depot/autogel 120 mg for the control of carcinoid syndrome (CS) symptoms in patients with neuroendocrine tumors (NETs).

METHODS

This was a 16-week, randomized, double-blind, phase 3 trial (Clinicaltrials.gov: NCT00774930). Patients with/without prior somatostatin analog (SSA) use were randomized to lanreotide depot/autogel 120 mg or placebo every 4 weeks, with access to short-acting octreotide as rescue medication. The primary endpoint was the percentage of days in which short-acting octreotide was used, which was assessed from daily diaries using an analysis of covariance including the stratification variables baseline short-acting octreotide use and frequency of diarrhea/flushing. The proportions of patients experiencing treatment success was a supportive analysis. Adverse events were recorded at all visits.

RESULTS

A total of 115 patients were enrolled (lanreotide, n = 59; placebo, n = 56). The adjusted mean (95% confidence interval [CI]) percentage of days with rescue octreotide use (primary endpoint) was significantly lower in the lanreotide (33.7%; 95% CI, 25.0%-42.4%) versus the placebo group (48.5%; 95% CI, 39.6%-57.4%), representing an absolute difference of -14.8% (95% CI, -26.8% to -2.8%; P = .017). The odds ratio of full/partial treatment success (≤3 days short-acting octreotide use weeks 12 to 15) was significantly greater with lanreotide than placebo (2.4; 95% CI, 1.1-5.3; P = .036). No new safety concerns were identified, and lanreotide was well tolerated.

CONCLUSION

Lanreotide depot/autogel is effective for the control of CS symptoms in patients (SSA-naïve or experienced) with NETs.

ABBREVIATIONS

AE = adverse event BMI = body mass index CS = carcinoid syndrome ELECT = Evaluating Lanreotide Efficacy and safety as a Carcinoid-syndrome Treatment HRQoL = health-related quality of life LTOLE = long-term open-label extension NET = neuroendocrine tumor OL = open label SSA = somatostatin analog.