Prognostic and predictive significance of p53 and ATRX in neuroendocrine neoplasms of GIT and pancreas and their utility as an adjunct to accurate diagnosis-An eight-year retrospective study.

INTRODUCTION: Neuroendocrine neoplasms of gastrointestinal tract (GIT) and pancreas are heterogenous tumors. World Health Organization (WHO) 2019 classification introduced Grade (G)3 neuroendocrine tumor (NET) distinct from neuroendocrine carcinoma (NEC), based on molecular differences and to triage the patients for appropriate therapy. This distinction largely relies on morphology, which can be challenging at times. Genomic profiling has revealed TP53 and RB1 mutations in NECs, while death domain-associated protein 6 (DAXX) and alpha-thalassemia/mental retardation X-linked (ATRX), in G3NET. Their role as biological markers in differentiating these entities and their significance as prognostic markers are not yet established. This study aims at analyzing the diagnostic and prognostic role of p53 and ATRX in neuroendocrine neoplasms of GIT and pancreas. METHODOLOGY: A single-centre, eight-year retrospective study of neuroendocrine neoplasm of GIT and pancreas comprised G2NET, G3NET and NEC. Tumor slides were stained by immunohistochemistry for p53 and ATRX. Strong nuclear staining of > 50% of tumor cells for p53 was considered mutated. Nuclear staining of ATRX in < 5% of tumor cells was considered ATRX loss. Expression of p53 and ATRX was analyzed and correlated with tumor grades and patient survival. RESULTS: Fifty-five patients with gastro-entero-pancreatic neuroendocrine neoplasm were studied, comprising G2NET (58%), G3NET (16%) and NEC (26%). Median age of diagnosis was 59 years with male predominance. The pancreas was the most common site followed by the small bowel. NEC showed lower survival compared to G3 and G2NET. Mutated p53 immunohistochemical expression was more frequent among NEC than G3NET. Patients with mutated p53 had significantly lower survival irrespective of the grade (p = 0.001). There was no association of ATRX loss with grade or survival. CONCLUSION: G3NETs are genetically different from NECs. Use of immunohistochemistry for p53 in addition to histomorphology may facilitate accurate categorization of NEC and G3NET. Mutated p53 may also be used as an independent prognostic marker in neuroendocrine tumors of GIT and pancreas.

Case report: Recurrence of primary hepatic neuroendocrine tumors after resection of liver segments IV in 8 years follow-up.

Background: Primary hepatic neuroendocrine tumors (PHNETs) are an utterly rare entity. The diagnosis of PHNETs could legitimize when an extrahepatic primary NET must always be excluded. PHNETs can achieve a high survival rate after complete surgical resection, however, most patients still have an 18% risk of recurrence within 5 years after surgery. In our case, the recurrence occurred 8 years after the first hepatectomy, which is relatively rare in the current literature. Therefore, rigorous postoperative follow-up is necessary for early detection and timely treatment of recurrent PHNETs. Case information: We report a case of PHNET in a 24-year-old previously healthy female patient who relapsed 8 years after hepatectomy. This case focuses on the importance of diagnosis of primary and recurrent PHNETS in young patients, rare pathological types, and post-operative follow-up. Conclusion: This case report detailed the rare pathological morphology and characteristic immunohistochemical markers in our case for PHNETS, which enhanced the new understanding of the diagnosis of this entity. In addition, we also highlighted the variable duration of recurrence after treatment of PHNETs. The 8-year recurrent period in our case suggests the importance of regular examination in patients with PHNETs by following the doctor's instructions.

Enhancer landscape of lung neuroendocrine tumors reveals regulatory and developmental signatures with potential theranostic implications.

Well-differentiated low-grade lung neuroendocrine tumors (lung carcinoids or LNETs) are histopathologically classified as typical and atypical LNETs, but each subtype is still heterogeneous at both the molecular level and its clinical manifestation. Here, we report genome-wide profiles of primary LNETs' cis-regulatory elements by H3K27ac ChIP-seq with matching RNA-seq profiles. Analysis of these regulatory landscapes revealed three regulatory subtypes, independent of the typical/atypical classification. We identified unique differentiation signals that delineate each subtype. The "proneuronal" subtype emerges under the influence of ASCL1, SOX4, and TCF4 transcription factors, embodying a pronounced proneuronal signature. The "luminal-like" subtype is characterized by gain of acetylation at markers of luminal cells and GATA2 activation and loss of LRP5 and OTP. The "HNF+" subtype is characterized by a robust enhancer landscape driven by HNF1A, HNF4A, and FOXA3, with notable acetylation and expression of FGF signaling genes, especially FGFR3 and FGFR4, pivotal components of the FGF pathway. Our findings not only deepen the understanding of LNETs' regulatory and developmental diversity but also spotlight the HNF+ subtype's reliance on FGFR signaling. We demonstrate that targeting this pathway with FGF inhibitors curtails tumor growth both in vitro and in xenograft models, unveiling a potential vulnerability and paving the way for targeted therapies. Overall, our work provides an important resource for studying LNETs to reveal regulatory networks, differentiation signals, and therapeutically relevant dependencies.

Small cell neuroendocrine carcinoma in maxillary sinus: a case report and literature review.

INTRODUCTION: Small cell neuroendocrine carcinoma is a rare and aggressive pathology with significant diagnostic challenges. Treatment typically involves multimodal therapy, including surgery and chemotherapy, but outcomes vary. The objective of this study is to describe and report a case of small cell neuroendocrine carcinoma. CASE PRESENTATION: A case study illustrates the follow-up of a 36-year-old female patient from diagnostic biopsy to maxillectomy, followed by adjuvant chemotherapy with cisplatin and etoposide. Small cell neuroendocrine carcinoma poses significant challenges due to its rarity and aggressive behavior. DISCUSSION: Multimodal therapy remains the mainstay, but the prognosis is unfavorable. Despite advances, managing small cell neuroendocrine carcinoma remains challenging. CONCLUSIONS: Integrated approaches are crucial, underscoring the need for ongoing research to improve outcomes in this rare malignancy.

Epidemiological, Clinical and Biological Hemogram Features in a Cohort of Neuroendocrine Tumor Patients.

We conducted a retrospective study based on 55 patients diagnosed with gastroenteropancreatic neuroendocrine tumors (GEP-NETs)-gastric (G-NET), small bowel (SB-NET) and colonic (C-NET), hospitalized and evaluated within the Surgical, Gastroenterology and Internal Medicine Clinics, in The Clinical Emergency County Hospital Craiova, between May 2016 and April 2024. We aimed in this study to analyze the epidemiological aspects and clinical characteristics of patients with GEP-NETs. In our study group, the patients' ages were between 39-82 years, with a mean of 66.40 (±12.46) years. The incidence of GEP-NETs cases in young patients was insignificant low-1 case. 45.46% of all patients lived in urban areas. 16.36% were G-NET, 14,54 were SB-NET and 69.09% were C-NET. The GEP-NETs diagnosis was established by immunohistochemistry features. Also, we observed that the most frequency localization was on the ascending colon, while the rarest on the colon it is located on the transverse colon and the rarest is on the small bowel, in spite of the generally literature data. From the C-NET group, 49.09% have been presented arterial hypertension probable explained by serotonin and dopamine secretion an inflammatory through phenotype expression and just one patient has been presented an erythematous psoriasis, which could be also explained by the same neurotransmitter's involvement as a possible purposed mechanism. The results obtained in our study demonstrate that could be a common profile of GEP-NETs patients through epidemiological general information and clinical characteristics. Also, we demonstrate that, in the last years, the incidence increased for the GEP-NETs.

Peptide-guided adaptor-CAR T-Cell therapy for the treatment of SSTR2-expressing neuroendocrine tumors.

Somatostatin receptor type 2 (SSTR2) is one of the five subtypes of somatostatin receptors and is overexpressed on the surface of most gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs), pituitary tumors, paraganglioma, and meningioma, as well as hepatocellular carcinoma and breast cancer. Chimeric antigen receptor (CAR) T-cells are genetically engineered to express an artificial, T-cell activating binder, leading upon ligation to biocidal activity against target-antigen expressing cells. Adaptor-CAR T-cells recognize, via the CAR, a tag on an antigen-binding molecule, building an activating bridge between the CAR and the target cell. We hypothesized that a novel fluorescent-peptide antagonist of SSTR2, called Octo-Fluo, in combination with anti-FITC adaptor CAR (AdFITC(E2)-CAR) T-cells, may function as an on-off tunable activating bridge between the CAR and SSTR2 expressing target cells. In vitro studies confirmed the binding of Octo-Fluo to Bon1-SSTR2 mCherry-Luc cells without evidence of internalization. AdFITC(E2)-CAR T-cells were activated and efficiently induced Bon1-SSTR2 cell death in vitro, in an Octo-Fluo concentration-dependent manner. Similarly, AdFITC(E2)-CAR T-cells in combination with Octo-Fluo efficiently infiltrated the tumor and eliminated Bon1-SSTR2 tumors in immunodeficient mice in therapeutic settings. Both, AdFITC(E2)-CAR T-cell tumor infiltration and biocidal activity were Octo-Fluo concentration-dependent, with high doses of Octo-Fluo, saturating both the CAR and the SSTR2 antigen independently, leading to the loss of tumor infiltration and biocidal activity due to the loss of bridge formation. Our findings demonstrate the potential of using AdFITC(E2)-CAR T-cells with Octo-Fluo as a versatile, on-off tunable bispecific adaptor for targeted CAR T-cell immunotherapy against SSTR2-positive NETs.

Clinical Predilection Features of Middle Ear Adenomatous Neuroendocrine Tumors: A Review of 10 Patients and a Special Case Is Attached.

Introduction: Middle ear adenomatous neuroendocrine tumors (MEANTs) are rare middle ear lesions characterized by nonspecific symptoms, signs, and imaging findings. Diagnosis typically relies on postoperative pathological assessment. This study investigated the diagnostic utility of the predilection sites and clinical characteristics of MEANTs. Methods: A retrospective analysis was conducted on clinical data from 10 patients with histologically confirmed MEANTs, admitted to Eye & ENT Hospital of Fudan University between March 2016 and March 2023. Results: The median age of the patients at diagnosis was 39.3 years. Hearing loss (n = 8) and ear pain (n = 6) were the most prevalent clinical symptoms in the patients diagnosed with MEANTs. Endoscopic examination revealed diverse symptoms, predominantly presenting as non-pulsatile masses with distinct boundaries and quasi-circular shapes within the external auditory canal, often accompanied by abundant blood vessels (n = 4). Tumors were typically confined to the middle/lower tympanic chambers or eustachian tube and were frequently associated with tympanic sclerosis, particularly around the pharyngeal tube (n = 3). Pathologically, MEANTs exhibited CD56 positivity or weak positivity, along with positive staining for CKpan and Syn, negativity for S100, and Ki67 ≤3%. Personalized surgical interventions were chosen by all the patients based on lesion severity, with no subsequent radiotherapy or chemotherapy administered postoperatively. No tumor progression was noted during the postoperative follow-up. In addition, a noteworthy case was presented in which MEANT initially manifested in the middle or lower tympanic cavity and eustachian tubes. Over 2 years, the tumor progressively grew, invading the middle tympanum and surrounding ossicles, ultimately achieving complete resection with no recurrence observed during subsequent follow-up. Conclusions: A possible diagnosis of middle ear adenoma should be considered when encountering non-pulsatile tumors with clearly demarcated inner boundaries within the external auditory canal accompanied by abundant quasi-circular vessels and the presence of new bone or neoplasm at the pharyngeal tympanic canal orifice observed during preoperative examinations or surgical procedures.

Decoding the identity of rare tumors.

Solitary fibrous tumors have gene expression signatures similar to those of neuroendocrine tumors.

ESR Essentials: role of PET/CT in neuroendocrine tumors-practice recommendations by the European Society for Hybrid, Molecular and Translational Imaging.

Neuroendocrine neoplasms (NEN) originate from the secretory cells of the neuroendocrine system, with the majority arising in the gastrointestinal tract and pancreas. Given the heterogeneity in the biological behavior and morphological differentiation of these tumors, advanced imaging techniques are crucial for supporting the suspected diagnosis, accurate staging, and monitoring therapy. As most well-differentiated NEN demonstrate overexpression of somatostatin receptors (SSR) on the cell surface, SSR-directed PET/CT is considered the reference standard for imaging of this particular entity. SSR-PET/CT should be the imaging method of choice in every NEN G1 or G2 and considered for re-staging after both potentially curative and non-curative surgeries. The extent of SSR expression is also crucial for determining a patient's eligibility for peptide receptor radionuclide therapy (PRRT). PRRT utilizes [177Lu]Lu-DOTA-TATE to target the SSR receptor and can significantly prolong progression-free survival in patients with advanced, progressive neuroendocrine tumor of the gastroenteropancreatic system (GEP-NET). PET/CT is a central component of the multidisciplinary management of NEN. Variable follow-up intervals are recommended, considering that tumors with higher proliferation rates or advanced metastatic disease require more frequent assessments. The combination with other imaging modalities, like MRI, complements SSR-PET/CT, further enhancing overall diagnostic accuracy. KEY POINTS: Somatostatin receptor-PET/CT (SSR-PET/CT) is the guideline-recommended reference standard for imaging well-differentiated neuroendocrine tumors (NET). SSR-PET/CT should be the diagnostic imaging of choice for staging and post-therapy re-staging of grade 1 or 2 NET (G1 or G2). Variable follow-up intervals are recommended for NET G1 and G2. Tumors with higher proliferation rates or advanced metastatic disease necessitate more frequent assessments.

Radiomics Analysis for Clinical Decision Support in 177Lu-DOTATATE Therapy of Metastatic Neuroendocrine Tumors using CT Images.

Background: Radiomics is the computation of quantitative image features extracted from medical imaging modalities to help clinical decision support systems, which could ultimately meliorate personalized management based on individual characteristics. Objective: This study aimed to create a predictive model of response to peptide receptor radionuclide therapy (PRRT) using radiomics computed tomography (CT) images to decrease the dose for patients if they are not a candidate for treatment. Material and Methods: In the current retrospective study, 34 patients with neuroendocrine tumors whose disease is clinically confirmed participated. Effective factors in the treatment were selected by eXtreme gradient boosting (XGBoost) and minimum redundancy maximum relevance (mRMR). Classifiers of decision trees (DT), random forest (RF), and K-nearest neighbors (KNN) with selected quantitative and clinical features were used for modeling. A confusion matrix was used to evaluate the performance of the model. Results: Out of 866 quantitative and clinical features, nine features with the XGBoost method and ten features with the mRMR pattern were selected that had the most relevance in predicting response to treatment. Selected features of the XGBoost method in integration with the RF classifier provided the highest accuracy (accuracy: 89%), and features selected by the mRMR method in combination with the RF classifier showed satisfactory performance (accuracy: 74%). Conclusion: This exploratory analysis shows that radiomic features with high accuracy can effectively predict response to personalize treatment.

Rapid Evolution of Metastases in Patients with Treated G3 Neuroendocrine Tumors Associated with NEC-Like Transformation and TP53 Mutation.

Little is known about the morphomolecular features of G3 neuroendocrine tumors (G3NETs) under prolonged systemic treatments, although rapid progression is increasingly observed. This longitudinal study aims to elucidate the course and morphomolecular features of metastasized G3NETs with high-grade transformation. Clinical and histological findings in 40 patients with metastasized and treated G3NETs, which were histologically examined at least twice with an interval time of more than 6 months (median 27), were reviewed and the morphomolecular changes recorded and assigned to treatment. Neuroendocrine carcinoma (NEC)-like histology defined by high-grade atypia, diffuse growth pattern, and/or necrosis was identified in nine (22%) G3NETs (seven pancreatic, two rectal) patients. All NEC-like tumors showed a significantly higher Ki67 increase and longer interval time between first and last examination than non-NEC-like G3NETs (53 vs. 19% and 60 vs. 24 months, respectively). Moreover, all NEC-like G3NETs had TP53 (100%), but rarely RB1 (12%) mutations, and retained NET-typical mutations such as MEN1 or DAXX (five of the pancreatic NETs). The last treatments received prior to the NEC-like transformation included PRRT (n = 3), somatostatin analog, everolimus, sunitinib (n = 1 each), and alkylating agents (n = 2). Abrupt clinical progression in patients with metastasized G3NETs is associated with a significant increase in Ki67, accelerated growth, and NEC-like histology. These findings are most likely attributable to the novel TP53 mutation, which was detected in all nine cases at the last evaluation. However, none of the cases exhibited a complete transformation to a typical NEC, as the tumors retained partial histological and genetic features of NETs.

Insulinoma-associated protein 1 (INSM1) immunohistochemical expression in normal, hyperplastic, and neoplastic canine neuroendocrine tissues.

Insulinoma-associated protein 1 (INSM1), a recently identified neuroendocrine marker, is a transcriptional regulator with highly conserved INSM1 homologues in various species. This study investigated the immunohistochemical reactivity of the INSM1 antibody in 20 normal canine neuroendocrine tissues from various anatomical locations, 87 hyperplastic or neoplastic tissues of neuroendocrine origin, and 62 non-neuroendocrine neoplasms and compared the results with those of chromogranin A and synaptophysin in neuroendocrine neoplasms. Western blot was performed on fresh canine pituitary glands and canine parathyroid glands to confirm the specificity of the anti-INSM1 antibody. The results showed that the anti-INSM1 antibody could detect nuclear expression in normal canine neuroendocrine tissues, except for the parathyroid glands. INSM1 was detectable in 79/87 (91%) of the hyperplastic and neoplastic neuroendocrine lesions, but all parathyroid carcinomas and parathyroid adenomas (three samples each) were negative for INSM1. In contrast, INSM1 was detected in only one of 62 (2%) non-neuroendocrine neoplasms. The overall percentage of neuroendocrine neoplasms that immunolabeled positively for all three markers was 89%. In addition, the nuclear expression of INSM1 was easier to interpret than that of chromogranin A or synaptophysin. These findings confirm that INSM1 is a useful immunohistochemical marker for diagnosing canine neuroendocrine neoplasms, except for parathyroid neoplasms, and should be considered as part of immunohistochemistry panels to improve diagnostic capability.

Various Markers of Neuroendocrine Tumor: A Narrative Review.

Neuroendocrine tumors (NETs) are uncommon tumors that develop from specialized endocrine cells. Thyroid medullary carcinoma, phaeochromocytomas, pituitary tumors, carcinoid, and gastroenteropancreatic NET are just a few examples of the diverse group known as NET. In recent times, they have garnered significant interest due to their ease of palliation and ability to reveal the long-term impact of the specific hormone raised. Neuroendocrine indicators, particularly chromogranin A, are very helpful in the diagnostic process. Accurate biomarkers that can be employed for NET diagnosis, prognosis and follow-up, therapy stratification, and treatment response evaluation are greatly needed. Due to the great diversity of neuroendocrine neoplasms, particular biomarkers must be developed in order to diagnose, treat, and identify them. The several NET biomarkers covered in this review will aid in the fight against this uncommon illness.

Unveiling a Small Bowel Obstruction: A Case of a Neuroendocrine Ileal Tumor.

Neuroendocrine tumors (NETs) are rare, slow-growing tumors originating from the diffuse neuroendocrine cell system, predominantly affecting the digestive tract. Small bowel neuroendocrine tumors (SBNETs) may present with nonspecific symptoms, such as abdominal pain, or with intermittent intestinal obstruction. This case outlines the diagnostic journey of a septuagenarian male with prolonged abdominal symptoms and weight loss. Despite extensive investigation, a definitive cause remained elusive. Recurrent partial intestinal obstruction led to surgical exploration and segmental resection. Pathology confirmed a NET. The case underscores the importance of considering intestinal neoplasia in older patients with recurrent partial small bowel obstruction.

Endoscopic Ultrasound-Guided Radiofrequency Ablation of Metastatic Pancreatic VIPoma: A Novel Treatment.

VIPomas are a rare type of functional pancreatic neuroendocrine tumors (PNETs), causing symptoms due to their hypersecretion in the gastrointestinal tract. The rare association of PNETs with tumors of endocrine organs such as pituitary and parathyroid glands is called multiple endocrine neoplasia (MEN1) syndrome. Due to their indolent course, VIPomas often present late in the illness and may already have metastatic disease. The index case had MEN1 syndrome with biopsy-proven small sub-centimetric metastatic VIPoma and a history of parathyroidectomy for nodules in the past. The patient had a suspicion of pancreatic cholera and, after an appropriate workup, was treated by endoscopic ultrasound (EUS)-guided radiofrequency ablation (RFA) of the metastatic pancreatic VIPomas. EUS-guided RFA is a procedure by which the lesions are viewed under endoscopic ultrasound and undergo coagulative necrosis due to the high temperatures the tissue is subjected to. The application of EUS-guided radiofrequency ablation for sub-centimetric metastatic pancreatic VIPoma as a daycare procedure can be a valuable tool in its management.

Analysis of gut microbiota-derived metabolites regulating pituitary neuroendocrine tumors through network pharmacology.

Pituitary neuroendocrine tumors (PitNETs) are a special class of tumors of the central nervous system that are closely related to metabolism, endocrine functions, and immunity. In this study, network pharmacology was used to explore the metabolites and pharmacological mechanisms of PitNET regulation by gut microbiota. The metabolites of the gut microbiota were obtained from the gutMGene database, and the targets related to the metabolites and PitNETs were determined using public databases. A total of 208 metabolites were mined from the gutMGene database; 1,192 metabolite targets were screened from the similarity ensemble approach database; and 2,303 PitNET-related targets were screened from the GeneCards database. From these, 392 overlapping targets were screened between the metabolite and PitNET-related targets, and the intersection between these overlapping and gutMGene database targets (223 targets) were obtained as the core targets (43 targets). Using the protein-protein interaction (PPI) network analysis, Kyoto encyclopedia of genes and genomes (KEGG) signaling pathway and metabolic pathway analysis, CXCL8 was obtained as a hub target, tryptophan metabolism was found to be a key metabolic pathway, and IL-17 signaling was screened as the key KEGG signaling pathway. In addition, molecular docking analysis of the active metabolites and target were performed, and the results showed that baicalin, baicalein, and compound K had good binding activities with CXCL8. We also describe the potential mechanisms for treating PitNETs using the information on the microbiota (Bifidobacterium adolescentis), signaling pathway (IL-17), target (CXCL8), and metabolites (baicalin, baicalein, and compound K); we expect that these will provide a scientific basis for further study.

Risk factors for regional lymph node metastasis in rectal neuroendocrine tumors: a population-based study.

Introduction: The identification of risk factors for regional lymph node (r-LN) metastasis in rectal neuroendocrine tumors (R-NETs) remains challenging. Our objective was to investigate the risk factors associated with patients diagnosed with R-NETs exhibiting r-LN metastasis. Methods: Patient information was obtained from the Surveillance, Epidemiology, and End Results (SEER) database, complemented by data from the West China Hospital (WCH) databases. The construction cohort comprised patients diagnosed with R-NETs from the SEER database, while cases from the WCH database were utilized as the validation cohort. A novel nomogram was developed to predict the probability of r-LN metastasis, employing a logistic regression model. Results: Univariate analysis identified four independent risk factors associated with poor r-LN metastasis: age (HR = 1.027, p < 0.05), grade (HR = 0.010, p < 0.05), T stage (HR = 0.010, p < 0.05), and tumor size (HR = 0.005, p < 0.05). These factors were selected as predictors for nomogram construction. Discussion: The novel nomogram serves as a reliable tool for predicting the risk of r-LN metastasis, providing clinicians with valuable assistance in identifying high-risk patients and tailoring individualized treatments.