Non-functional alpha-cell hyperplasia with glucagon-producing NET: a case report.

Introduction: Alpha-cell hyperplasia (ACH) is a rare pancreatic endocrine condition. Three types of ACH have been described: functional or nonglucagonoma hyperglucagonemic glucagonoma syndrome, reactive or secondary to defective glucagon signaling, and non-functional. Few cases of ACH with concomitant pancreatic neuroendocrine tumors (pNETs) have been reported and its etiology remains poorly understood. A case report of non-functional ACH with glucagon-producing NET is herein presented. Case report: A 72-year-old male was referred to our institution for a 2 cm single pNET incidentally found during imaging for acute cholecystitis. The patient's past medical history included type 2 diabetes (T2D) diagnosed 12 years earlier, for which he was prescribed metformin, dapagliflozin, and semaglutide. The pNET was clinically and biochemically non-functioning, apart from mildly elevated glucagon 217 pg/ml (<209), and 68Ga-SSTR PET/CT positive uptake was only found at the pancreatic tail (SUVmax 11.45). The patient underwent a caudal pancreatectomy and the post-operative 68Ga-SSTR PET/CT was negative. A multifocal well-differentiated NET G1, pT1N0M0R0 (mf) strongly staining for glucagon on a background neuroendocrine alpha-cell hyperplasia with some degree of acinar fibrosis was identified on pathology analysis. Discussion and conclusion: This case reports the incidental finding of a clinically non-functioning pNET in a patient with T2D and elevated glucagon levels, unexpectedly diagnosed as glucagon-producing NET and ACH. A high level of suspicion was required to conduct the glucagon immunostaining, which is not part of the pathology routine for a clinically non-functioning pNET, and was key for the diagnosis that otherwise would have been missed. This case highlights the need to consider the diagnosis of glucagon-producing pNET on an ACH background even in the absence of glucagonoma syndrome.

Navigating the diagnostic gray zone: a challenging case of pancreatic high-grade neuroendocrine neoplasm.

BACKGROUND: Grade 3 neuroendocrine tumor (G3 PanNET) and poorly differentiated neuroendocrine carcinoma (PanNEC) of the pancreas are considered distinct entities from a biological and prognostic perspective but may have overlapping features complicating a definitive diagnosis. CASE PRESENTATION: A 52-year-old female presented with a pancreatic body mass and liver lesions. Initial biopsies showed variable lower- and higher-grade morphologies and modestly elevated Ki67 proliferation index up to 30%, leading to a diagnosis of G3 PanNET. The patient underwent everolimus treatment followed by surgical resection, revealing a complex tumor with features of both G3 PanNET and PanNEC, including admixed well- and poorly differentiated morphologies, modestly elevated hotspot Ki67 of 28%, retained ATRX/DAXX expression, and loss of RB expression. The final diagnosis rendered was "high-grade neuroendocrine neoplasm" with discussion of both entities in the differential. Post-operatively, the patient remains alive with stable metastases. CONCLUSIONS: This case highlights the diagnostic complexities of distinguishing G3 PanNET and PanNEC even with the support of ancillary immunohistochemical and molecular studies. In addition, such cases raise the possibility that G3 PanNET and PanNEC may lie on a spectrum of disease with potential biological overlap.

Advances in Management of Nonfunctional Pancreas Neuroendocrine Tumors.

This article presents updates in the surgical management of non-functional sporadic pancreas neuroendocrine tumors NET, including considerations for assessment of biologic behavior to support decision-making, indications for surgery, and surgical approaches tailored to the unique nature of neuroendocrine tumors.

Neuroendocrine neoplasms of the thymus.

Neuroendocrine neoplasms of the thymus (tNENs), including typical carcinoid, atypical carcinoid, large cell neuroendocrine carcinoma, and small cell carcinoma, are rare tumors with scarce clinical and pathological data available in the literature. They share many common features with neuroendocrine neoplasms in other organs, such as those in the lungs, while demonstrating some distinct clinical and pathological features. This review aims to give an updated overview of each category of tNENs, focusing primarily on the pathologic diagnosis and differential diagnosis of these tumors.

Giant laryngeal neuroendocrine neoplasm causing airway obstruction: A case report and literature review.

RATIONALE: Laryngeal neuroendocrine neoplasm (NEN) is a rare and heterogeneous disease that originates from neuroendocrine cells. It mainly occurs in middle-aged and elderly men. Due to the lack of specific clinical and imaging manifestations, diagnosis and treatment of the disease pose a challenge. Therefore, a consensus on the diagnosis and treatment of the disease is necessary. By discussing this case, we will be able to gain further insight into laryngeal NEN and will be able to provide some recommendations for the future management of this rare disease. PATIENT CONCERNS: A 67-year-old man was admitted to our department with a history of sore throat and dyspnea. After admission, the patient experienced acute airway obstruction and experienced an emergency bedside tracheotomy. DIAGNOSES: Flexible fiberoptic laryngoscopy and enhanced CT showed a cauliflower-like mass in the left supraglottic region and obstructed most of the laryngeal cavity. We biopsied the mass, and the pathology showed a poorly differentiated adenocarcinoma. INTERVENTIONS: A horizontal hemilaryngectomy and left neck dissection were performed. At 4 weeks after the operation, the patient underwent chemotherapy and radical radiotherapy. OUTCOMES: After a 1-year postoperative follow-up, the patient recovered well and showed no signs of recurrence. LESSONS: Laryngeal neuroendocrine neoplasm is very rare, early diagnosis remains difficult. Radical surgery combined with postoperative chemoradiotherapy is currently the most appropriate treatment.

GATIS score for predicting the prognosis of rectal neuroendocrine neoplasms: A Chinese multicenter study of 12-year experience.

BACKGROUND: There is currently a shortage of accurate, efficient, and precise predictive instruments for rectal neuroendocrine neoplasms (NENs). AIM: To develop a predictive model for individuals with rectal NENs (R-NENs) using data from a large cohort. METHODS: Data from patients with primary R-NENs were retrospectively collected from 17 large-scale referral medical centers in China. Random forest and Cox proportional hazard models were used to identify the risk factors for overall survival and progression-free survival, and two nomograms were constructed. RESULTS: A total of 1408 patients with R-NENs were included. Tumor grade, T stage, tumor size, age, and a prognostic nutritional index were important risk factors for prognosis. The GATIS score was calculated based on these five indicators. For overall survival prediction, the respective C-indexes in the training set were 0.915 (95% confidence interval: 0.866-0.964) for overall survival prediction and 0.908 (95% confidence interval: 0.872-0.944) for progression-free survival prediction. According to decision curve analysis, net benefit of the GATIS score was higher than that of a single factor. The time-dependent area under the receiver operating characteristic curve showed that the predictive power of the GATIS score was higher than that of the TNM stage and pathological grade at all time periods. CONCLUSION: The GATIS score had a good predictive effect on the prognosis of patients with R-NENs, with efficacy superior to that of the World Health Organization grade and TNM stage.

Ileo-Ileal Intussusception Secondary to Neuroendocrine Tumor in Adult Patient.

BACKGROUND Intussusception occurs when a proximal region of the intestine telescopes into a distal region. It is more common in the pediatric population, with only 5% of cases occurring in adults. The most frequent causes of adult intussusception are malignancy, polyps, or diverticula. A very rare cause is neuroendocrine tumor (NET). NETs are a diverse group of neoplasms that arise from endocrine cells throughout the body. Here, we present a case of a patient who presented with ileo-ileal intussusception due to a T3N1 NET, grade 1. CASE REPORT A 60-year-old man with a medical history of peptic ulcer disease presented for evaluation of lower abdominal pain, dark "maroon" colored stools, and hematemesis for the past 2 days. Computed tomography (CT) of the abdomen and pelvis showed ileo-ileal intussusception. Exploratory laparotomy revealed a small bowel mass approximately 30 cm from the ileocecal valve. After removal of 15 cm of small bowel and 13 lymph nodes, pathology confirmed the diagnosis of a T3N1 NET, grade 1. He was subsequently referred to the Oncology Department, where he was cleared, with no need for additional surveillance. CONCLUSIONS In adult patients presenting with nonspecific abdominal pain and concern for small bowel obstruction, a CT scan can be helpful in diagnosing intussusception. When dealing with adult intussusception, the etiology needs to be carefully investigated to search for an underlying malignancy. In rare occasions, small bowel NETs can be the cause of intussusception and can therefore be identified early, before they metastasize and present with carcinoid syndrome.

Well-differentiated neuroendocrine tumors of the appendix: Diagnosis, differentials, and disease progression.

Well-differentiated neuroendocrine tumors are the most common neoplasm of the appendix. They are graded and staged using World Health Organization and American Joint Committee on Cancer criteria, respectively. They may be invisible grossly or form rounded yellow nodules, sometimes in the appendiceal tip. They show classic neuroendocrine tumor features microscopically, forming nests and cords of monotonous cells with salt-and-pepper chromatin and amphophilic cytoplasm. They are positive for neuroendocrine markers by immunohistochemistry, but their molecular characteristics are not well defined. pT-category staging relies primarily on tumor size, though higher-stage cases may involve the subserosa or mesoappendix. Few entities enter the differential diagnosis, but lesions such as goblet cell adenocarcinoma, poorly differentiated neuroendocrine carcinoma, and mixed neuroendocrine-non-neuroendocrine neoplasm may be considered. Appendiceal neuroendocrine tumors may metastasize to regional lymph nodes, but farther spread is rare. The most consistently proven risk factor for such spread is tumor size, though different studies have proposed different cutoffs. Other potential risk factors include lymphovascular invasion and margin positivity. Tumors smaller than 1 cm can be treated by appendectomy, while hemicolectomy is recommended for tumors larger than 2 cm. Proper treatment for cases measuring 1-2 cm remains a matter of debate.

A neuroendocrine biomarker revolution from monoanalyte to multianalyte biomarkers in non-functioning gastro-entero-pancreatic neuroendocrine neoplasms.

Neuroendocrine neoplasms (NENs) arise from neuroendocrine cells in a wide variety of organs. One of the most affected disease sites is the gastrointestinal system, which originates the gastro-entero-pancreatic NENs (GEP-NENs), a heterogenous group of malignancies that are rapidly increasing in incidence. These tumors can be functioning, with secretory activity leading to identifiable clinical syndromes, or non-functioning, with no secretory activity but with local symptoms of tumor growth and metastasis. A limitation in biomarkers is a crucial unmet need in non-secretory NEN management, as clinical decision-making is made more difficult by obstacles in tumor classification, prognostic evaluation, assessment of treatment response and surveillance. The objective of this review is to present existing and novel biomarkers for NENs that can function as prognostic factors and monitor disease progression or regression longitudinally, with a special emphasis on innovative research into novel multianalyte biomarkers.

Gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) - Current literature review of diagnostics and therapy. What has changed in the management?

<b>Introduction:</b> Gastro-entero-pancreatic neuroendocrine neoplasms (GEP-NENs) are malignancies originating from cells of the diffuse endocrine system. They are rare and localize in the upper and lower parts of the gastrointestinal tract and in the pancreas. Despite such a varied location, GEP-NENs are considered a common group of neoplasms due to the fact of their similar morphology and ability to secrete peptide hormones and biologically active amines. They are associated with clinical manifestations specific to the substances produced by a particular neoplasm. The classification of GEP-NENs is constantly systematized and updated based on their differentiation and grading. The development of available diagnostic and treatment methods for these tumors has made significant progress over the past 10 years and is still ongoing.<b>Aim:</b> In the following paper, we review the diagnostics and treatment of GEP-NENs, taking into account the latest molecular, immunological, or gene-based methods. Imaging methods using markers for receptors allow for high diagnostic sensitivity<b>Methods:</b> Medical databases were searched for the latest information. The authors also sought confirmation of the content of a particular publication in another publications, so as to present the most reliable information possible.<b>Results:</b> Research results revealed that the diagnostics and treatment of GEP-NENs have significantly advanced in recent years. Surgical interventions, especially minimally invasive techniques, have shown efficacy in treating GEP-NENs, with specific therapies such as somatostatin analogs, chemotherapy, and peptide receptor radionuclide therapy demonstrating promising outcomes. The evolution of diagnostic methods, including imaging techniques and biomarker testing, has contributed to improved patient care and prognosis.<b>Conclusions:</b> The increasing incidence of GEP-NENs is attributed to enhanced diagnostic capabilities rather than a rise in population prevalence. The study emphasizes the importance of ongoing research to identify specific markers for early detection and targeted therapies to further enhance the effectiveness of treating these rare and heterogeneous malignancies. The findings suggest a positive trajectory in the management of GEP-NENs, with future prospects focused on personalized and targeted treatment approaches.

Middle Ear Neuroendocrine Tumor: Case Report of a Tympanic Adenoma.

Middle ear neuroendocrine tumors (MeNETs) are an exceptionally rare occurrence. These benign tumors stem from the tympanic mucosa and can easily be misinterpreted by the clinician and the pathologist. Clinical characteristics, otoscopic findings and medical imaging in these cases are non-specific. We present a case of a 60-year-old male patient with bilateral hearing loss following recent coronavirus disease 2019 disease. Diagnostic work-up revealed a soft tissue neoplasm of the left middle ear. Surgical resection of the tumor mass with implantation of a partial ossicular replacement prosthesis (PORP) was the main modality of treatment. Middle ear neuroendocrine tumors was confirmed through positive immunohistochemistry for neuroendocrine tumor markers. Follow-up magnetic resonance imaging 12 months after the surgery reported no tumor recurrence or significant residual disease with a stable PORP. Our report highlights challenges in diagnosing and treating these rare tumors, while emphasizing surgical resection pitfalls and resulting improvement of quality of life of the patient. We recommend a through followup of patients with unclear soft tissue masses in the middle ear to obtain a definitive diagnosis.

[Diagnosis and management of patients with pheochromocytoma/paraganglioma: Consensus of experts of the Russian Medical Society for Arterial Hypertension and the Multidisciplinary Group for the Diagnosis and Treatment of Neuroendocrine Tumors].

The understanding of the nature of catecholamine-secreting tumors has changed significantly in recent years, affecting terminology and classification. Phaeochromocytoma/paraganglioma (PCC/PG) is a rare neuroendocrine tumor from chromaffin tissue that produces and secretes catecholamines. The incidence of PCC/PG is relatively low, with 2-8 cases per 1 million population per year; among patients with arterial hypertension, their prevalence is 0.2-0.6%. However, delayed diagnosis of PCC/PG is associated with a high risk of cardiovascular complications and a high mortality rate. The consensus presents the clinical manifestations of the disease with an emphasis on the course of arterial hypertension as the most common symptom in PCC/PG; modern ideas about the features of diagnosis, aspects of preoperative preparation, treatment, and follow-up of patients with PCC/PG are considered.

Early detection of multiple endocrine neoplasia type 1: A case report.

BACKGROUND: Multiple endocrine neoplasias (MENs) are a group of hereditary diseases involving multiple endocrine glands, and their prevalence is low. MEN type 1 (MEN1) has diverse clinical manifestations, mainly involving the parathyroid glands, gastrointestinal tract, pancreas and pituitary gland, making it easy to miss the clinical diagnosis. CASE SUMMARY: We present the case of a patient in whom MEN1 was detected early. A middle-aged male with recurrent abdominal pain and diarrhea was admitted to the hospital. Blood tests at admission revealed hypercalcemia and hypophosphatemia, and emission computed tomography of the parathyroid glands revealed a hyperfunctioning parathyroid lesion. Gastroscopy findings suggested a duodenal bulge and ulceration. Ultrasound endoscopy revealed a hypoechoic lesion in the duodenal bulb. Further blood tests revealed elevated levels of serum gastrin. Surgery was performed, and pathological analysis of the surgical specimens revealed a parathyroid adenoma after parathyroidectomy and a neuroendocrine tumor after duodenal bulbectomy. The time from onset to the definitive diagnosis of MEN1 was only approximately 1 year. CONCLUSION: For patients who present with gastrointestinal symptoms accompanied by hypercalcemia and hypophosphatemia, clinicians need to be alert to the possibility of MEN1.

Primary intraspinal neuroendocrine tumor: A case report and literature review.

RATIONALE: Neuroendocrine tumors (NET) refer to a group of uncommon tumors arising in the neuroendocrine system. Most NETs occur in the digestive tract and bronchi but are rare in the central nervous system, especially in the spinal canal. NET in the central nervous system mainly metastasize from other systems, with non-specific clinical symptoms. In this study, we report the diagnosis and treatment of intraspinal NET to provide clinical guidance as well as to avoid misdiagnosis and missed diagnosis. PATIENT CONCERNS: A 59-year-old male patient, presented with recurrent right lower limb pain for half a year, accompanied by numbness and weakness for 4 months and aggravation for 2 months. Lumbar spine magnetic resonance imaging (MRI) revealed a space-occupying lesion in the spinal canal. The diagnosis of primary intraspinal NET was confirmed by topathological examination. DIAGNOSIS: Primary intraspinal NET tumor. INTERVENTIONS: Surgical resection. OUTCOMES: Significant improvements in right lower limb pain, numbness, and weakness were observed, and lumbar spine MRI was performed again to dynamically observe the changes in intraspinal NET. CONCLUSIONS: Surgical resection may be an effective treatment for intraspinal NETs. LESSONS: Intraspinal NETs are relatively rare and mostly manifest as limb numbness, weakness, and pain. Due to its nonspecific clinical symptoms, intraspinal NETs are easily misdiagnosed as lumbar disc herniation with radiculopathy and lumbar spondylolisthesis. Therefore, in patients with long-term symptoms, in addition to common lumbar neuromuscular diseases, lumbar MRI should be performed promptly to exclude the possibility of lumbar NETs.

[Serotonin-Producing Pancreatic Neuroendocrine Neoplasm-A Case Report].

We experienced a case of resection of a pancreatic body bearing a serotonin-producing pancreatic neuroendocrine neoplasm( PanNEN). The patient was a female in her 70s. Contrast-enhanced CT of the pancreatic body showed a 12 mm tumor that was well enhanced in the early, portal, and equilibrium phases. The main pancreatic duct was stenosed at the tumor position, and the distal side was dilated. Although the contrast pattern was indicative of PanNEN, the stenosis of the main pancreatic duct suggested the possibility of invasive pancreatic ductal carcinoma. A serotonin-producing subtype of PanNEN, which causes stenosis of the main pancreatic duct despite its small diameter, was included in the differential diagnoses. We performed resection of the pancreatic body and tail with lymph node dissection. Pathological examination indicated that the tumor was PanNEN G1, and immunostaining revealed positivity for serotonin. Most PanNENs are not accompanied by stenosis of the main pancreatic duct. However, it has been reported that even a small-sized serotonin-producing PanNEN is likely to cause main pancreatic duct stenosis owing to its proliferation pattern. Although there are few reports of serotonin-producing PanNENs, an understanding of the characteristic imaging findings of this disease may be useful in the differential diagnosis of pancreatic tumors.

Modern Management of Gastric Neuroendocrine Neoplasms.

OPINION STATEMENT: Gastric neuroendocrine neoplasms (G-NENs) are a heterogeneous group of tumors that broadly fall into two groups. The first group, driven by oversecretion of gastrin, are generally multifocal, small, and behave indolently with a low (but non-zero) risk of progression and metastatic spread. They are conventionally categorized into type 1, with endogenous gastric-based overproduction of gastrin, and type 2 G-NEN, with overproduction of gastrin from an extra-gastric gastrin-secreting tumor. The second group, termed type 3 G-NEN, occur spontaneously and are potentially more aggressive, having a clinical course analogous to other neuroendocrine tumors of the gastrointestinal tract. Type 1 G-NEN can be managed with endoscopic surveillance and resection of visible lesions with great success, reserving surgery for the rare high-risk lesion, whereas surgical resection of the causative gastrin-secreting tumor in type 2 G-NEN is usually curative. Type 3 G-NEN is usually managed with formal surgical resection but there is growing evidence that limited surgery or even endoscopic resection in appropriately selected patients with low risk is both safe and effective. A novel subtype of G-NEN, associated with long-term proton pump inhibitor usage, is increasing in incidence. The pathophysiology seems to parallel type 1 G-NEN. In the setting of metastatic disease, which can occur in any subtype but is most common by far in type 3 G-NEN, the lack of trial data unique to G-NEN results in extrapolation of strategies and agents for treatment of non-gastric neuroendocrine disease. The rapid pace of development in this area is likely to benefit the metastatic G-NEN patient as well. As treatment is predicate on type of G-NEN, establishing the etiology of the lesion is crucial but growing knowledge of G-NEN pathophysiology and close collaboration between pathologists, gastroenterologists, radiologists, surgeons, and oncologists have enabled a growing trend towards de-escalation and less-invasive treatment paradigms.

Initial validation of the clinical significance of the NETest in Japanese gastroenteropancreatic neuroendocrine tumor patients.

As novel biomarkers for gastroenteropancreatic neuroendocrine tumors (GEPNET) are in demand, we aimed to validate the clinical value of the NETest in Japanese patients. Between 2021 and 2023, blood and clinical data were collected from patients with GEPNET. Among 35 patients (median age: 59 [49-66] years), 27 cases originated from the pancreas and eight from the gastrointestinal tract. Of 69 samples sent to the laboratory, 56 (81.2%) underwent NETest. The diagnostic sensitivity was 97.1%. Among three patients who underwent R0 resection and four treated with peptide receptor radionuclide therapy, the changes in NETest scores closely correlated with disease progression. The NETest demonstrated high diagnostic efficacy and accurate therapeutic monitoring capabilities in a Japanese population.

[Appendix ... it's not just appendicitis: neuroendocrine tumors.] / L'appendice... non è solo appendicite: i tumori neuroendocrini.

Well-differentiated neuroendocrine tumors of the appendix (NETs) are rare in pediatric and adolescent age groups. However, they are the most common gastrointestinal epithelial tumor in this age group and the most common malignancy of the appendix in the general population. The classification of these tumors considers factors such as the proliferation index, size of the neoplasm, and the presence of perineural and/or lymphovascular invasion, which can contribute to distant metastases. Preoperative diagnosis is challenging, except in cases where patients exhibit symptoms of carcinoid syndrome or signs of metastatic disease, which are uncommon in pediatric and adolescent patients. For tumors smaller than 1 cm, appendectomy is usually curative, while larger tumors or those at risk of spreading may require right hemicolectomy with lymphadenectomy. We present a case of an adolescent with NET and provide a literature review on the diagnostic and therapeutic approaches that should be considered for this relatively rare condition.Key words. Adolescent age, appendix, neuroendocrine tumors, pediatric age.

Pancreatic neuroendocrine tumor with abundant mitochondria.

A 40-year-old woman presented with dull, boring periumbilical region pain radiating to the back and vomiting for 1 year. Magnetic resonance cholangiopancreatography detected a polypoid growth in the ampullary region. The patient underwent Whipple's procedure. The specimen revealed a 4.9 × 4.5 × 3.7 cm tumor arising from the pancreas, abutting the posterior pancreatic surface and infiltrating the terminal common bile duct and the ampulla. Microscopic examination showed a pancreatic tumor composed of neuroendocrine cells. In addition, many large foci showing solid sheets of oncocytic cells with abundant granular eosinophilic cytoplasm were observed. Immunohistochemistry studies revealed positivity for synaptophysin, chromogranin, and Ki67 index above 70%. A diagnosis of oncocytic neuroendocrine tumor of Grade 3 was made. In electron microscopy, oncocytic cells showed abundant mitochondria dispersed throughout the cytoplasm. Oncocytic pancreatic neuroendocrine neoplasms are uncommon and can be diagnosed only on histopathological examination. These tumors tend to show a malignant behavior.