Search Results (126)

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are rare tumors with different clinical and biological characteristics. Ki-67 staining and mitotic counts are the most commonly used prognostic markers, but these methods are time-consuming and lack reproducibility, highlighting the need for innovative approaches that improve histological evaluation and prognosis. In our previous study, we observed that the microRNA (miRNA) expression profile of GEP-NENs correlates with the three grades of GEP-NENs. This study aimed to characterize a group of miRNAs that discriminate well-differentiated GEP-NENs grading 1 (G1) and grading (G2). Fifty formalin-fixed and paraffin-embedded tissue specimens from well-differentiated GEP-NENs G1 and G2 tissues were used for this study. The expression levels of 21 miRNAs were examined using qRT-PCR, while FGFR2 and FGF1 protein expression were evaluated through immunohistochemistry (IHC). We identified four miRNAs (hsa-miR-133, hsa-miR-150-5p, hsa-miR-143-3p and hsa-miR-378a-3p) that are downregulated in G2 GEP-NENs compared to G1. Bioinformatic analysis revealed that these miRNAs play a key role in modulating the FGF/FGFR signaling pathway. Consistent with this observation, we found that fibroblast growth factor receptor 2 (FGFR2) expression is markedly higher in G2 NENs patients, whereas its expression remains low in G1 NENs. Our findings highlight the potential use of miRNAs to confirm the histological evaluation of GEP-NENs by employing them as biomarkers for improving histological evaluation and tumor classification. Full article

Background: Functioning gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are rare tumors that secrete biologically active hormones, leading to complex clinical syndromes such as carcinoid syndrome, VIPoma, glucagonoma, gastrinoma, insulinoma, and somatostatinoma. These syndromes frequently induce profound metabolic, gastrointestinal, and nutritional disturbances. Objective: This review aims to provide a comprehensive overview of the physiopathology of malnutrition in functioning GEP-NENs and to highlight nutritional and supportive care strategies, including how medical, surgical, and locoregional treatments can indirectly improve nutritional outcomes. Methods: We analyzed the current literature and clinical guidelines to identify key mechanisms of malnutrition across different functioning syndromes and their clinical manifestations. Nutritional recommendations and the impact of treatment modalities on nutritional status were summarized. Results: The pathophysiology of malnutrition in functioning NENs is multifactorial and syndrome-specific. Hormonal hypersecretion may cause diarrhea, electrolyte imbalances, catabolic states, steatorrhea, or hypoglycemia, among other effects. These lead to nutrient loss, malabsorption, or altered intake. Tailored dietary interventions, micronutrient supplementation (e.g., niacin, calcium, vitamin B12), and symptom-guided nutritional support are essential. Somatostatin analogs, PRRT, and cytoreductive approaches often contribute to symptom control, thereby enhancing nutritional status and patient quality of life. Conclusions: Malnutrition in functioning GEP-NENs is a significant clinical issue that requires early recognition and a multidisciplinary, individualized management plan. Integrating nutrition into the comprehensive care of these patients is essential to improve outcomes and quality of life. Full article

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are a varied group of tumors that originate from neuroendocrine cells found throughout the gastrointestinal tract. These tumors encompass a broad spectrum of biological behaviors, ranging from slow-growing, well-differentiated neuroendocrine tumors (GEP-NETs) to aggressive and poorly differentiated neuroendocrine carcinomas (GEP-NECs), complicating their accurate classification and effective treatment. While advances in molecular research have refined our understanding of these tumors, their complexity, unpredictable progression, and differential response to therapies remain major clinical hurdles. A significant clinical challenge is the accurate grading and diagnosis of GEP-NENs, which is traditionally reliant on subjective methods. However, innovative technologies, such as artificial intelligence-based diagnostics, multi-omics approaches, and precision oncology, are now offering solutions for more precise and reliable classification. Meanwhile, emerging therapies aiming to activate the immune response or modify the tumor environment present promising avenues for improved outcomes. Realizing the full potential of these advances will require a thoughtful integration of molecular insights with standardized diagnostic practices and evolving therapeutic strategies, ensuring that progress in research meaningfully informs and enhances patient care across diverse clinical settings. This review discusses new advancements and explores future directions toward personalized and effective treatments for GEP-NENs. Full article

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a family of tumors that arise throughout the gastrointestinal tract. These tumors are heterogeneous, with complex clinical symptoms and tumor behaviors, and demonstrate rising incidence rates worldwide. In addition to their nature, GEP-NETs possess limited diagnostic and therapeutic options, which results in poor survival rates for patients with metastatic tumors. Given these findings, a further analysis of these tumors’ biology is needed to determine new therapeutic strategies. The tumor microenvironment (TME) consists of several residual cell populations and non-cellular components whose altered behavior creates a tumor-supportive niche. Studies from other cancers demonstrate the TME’s significance in tumor initiation, progression, and spread. In this review, we discuss efforts to characterize the TME in GEP-NETs. Preliminary studies of the immune system in GEP-NETs have led to several major clinical trials, with limited success. Efforts to target signaling crosstalk between cancer-associated fibroblasts, vascular endothelial cells, and tumor cells has led to major discoveries and multiple approved therapies. Finally, alterations to the extracellular matrix may lead towards an improved understanding of GEP-NET development, behavior, and improved detection methods. While research has rapidly expanded our knowledge within the last decade, further work is needed to bring our understanding of the GEP-NET TME in line with other rare cancers. Full article

Background: There is limited data on somatostatin receptor (SSTR) expression of metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NETs) using modern imaging techniques and stratifying by primary site and tumor grade (G). Understanding patterns of SSTR expression and tumor heterogeneity is essential when determining the relevance of cold and radiolabeled somatostatin analog treatments. Methods: A single-institutional retrospective analysis of metastatic well-differentiated G1-3 GEP-NET patients who underwent Gallium-68 ([⁶⁸Ga])-DOTATATE or Copper-64 ([⁶⁴Cu])-DOTATATE positron emission tomography (PET) imaging from September 2016 to June 2024 was performed. Results: A total of 1192 patients were considered eligible for this study. Among them, 26 (2.2%) were completely negative on SSTR PET/computed tomography (CT), and 27 (2.3%) had weak uptake (less or equal to the normal liver). Up to 40 (3.4%) had heterogeneous SSTR expression on PET/CT: 26 (2.2%) displayed the coexistence of strongly avid lesions with the absence or near absence of SSTR uptake in measurable tumors (heterogeneous strong), while 14 (1.2%) had a combination of absent and weakly expressing SSTR tumors (heterogeneous low). An additional nine cases with prior homogeneous expression (0.8%) developed new SSTR-negative tumors along with disease progression, potentially indicating dedifferentiation. The absent or heterogeneous SSTR expression rates were greater in NET G3 than G1/G2 and in tumors originating outside the small bowel (midgut). Most NETs with absent or heterogeneous SSTR expression were fluorodeoxyglucose-F-18 ([¹⁸F]FDG)-avid. Conclusions: The large majority of metastatic GEP-NETs demonstrate strong and relatively uniform SSTR expression, but approximately 8% are SSTR-negative, weak or heterogeneous on PET/CT. Higher than average rates of absent/heterogeneous/weak SSTR expression occur in G3 NETs and lower rates among small intestine primaries. Full article

Gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs) represent a rare and varied class of neoplasms, characterized by diverse clinical presentations and prognostic trajectories. Accurate and prompt diagnosis is vital to inform and optimize therapeutic decisions. Ultrasound, including standard B-mode imaging and advanced methods such as contrast-enhanced ultrasound (CEUS) and endoscopic ultrasound (EUS), serves as a key component in the diagnostic evaluation of these tumors. B-mode US and CEUS provide non-invasive, accessible methods for early detection and characterization. On B-mode imaging, GEP-NETs typically present as well-defined, hyperechoic, or iso-echoic lesions, while CEUS highlights their characteristic vascularity, marked by arterial-phase hyperenhancement and venous-phase washout. Compared to CT and MRI, ultrasound offers real-time, dynamic imaging without ionizing radiation or nephrotoxic contrast agents, making it particularly advantageous for patients requiring frequent monitoring or with contraindications to other imaging modalities. CT and MRI are widely regarded as the preferred methods for staging and surgical planning due to their detailed anatomical visualization. However, ultrasound, especially CEUS, provides a significant adjunctive role in both early detection and the follow-up on GEP-NETs. This analysis delves into the strengths, challenges, and innovations in ultrasound technology for diagnosing pancreatic NETs, focusing on its contribution to comprehensive imaging strategies and its impact on patient care decisions. Full article

Objectives: The aim of our study is to evaluate whether texture analysis of 68Ga-DOTATOC PET/CT images can predict clinical outcome in patients with neuroendocrine tumors (NET). Methods: Forty-seven NET patients who had undergone 68Ga-DOTATOC PET/CT were studied. Primary tumors were localized in the gastroenteropancreatic (n = 35), bronchopulmonary (n = 8), and other (n = 4) districts. NET lesions were segmented using an automated contouring program and subjected to texture analysis, thus obtaining the conventional parameters SUVmax and SUVmean, volumetric parameters of the primary lesion, such as Receptor-Expressing Tumor Volume (RETV) and Total Lesion Receptor Expression (TLRE), volumetric parameters of the lesions in the whole-body, such as wbRETV and wbTLRE, and texture features such as Coefficient of Variation (CoV), HISTO Skewness, HISTO Kurtosis, HISTO Entropy-log₁₀, GLCM Entropy-log₁₀, GLCM Dissimilarity, and NGLDM Coarseness. Patients were subjected to a mean follow-up period of 17 months, and survival analysis was performed using the Kaplan–Meier method and log-rank tests. Results: Forty-seven primary lesions were analyzed. Survival analysis was performed, including clinical variables along with conventional, volumetric, and texture imaging features. At univariate analysis, overall survival (OS) was predicted by age (p = 0.0079), grading (p = 0.0130), SUVmax (p = 0.0017), SUVmean (p = 0.0011), CoV (p = 0.0037), HISTO Entropy-log₁₀ (p = 0.0039), GLCM Entropy-log₁₀ (p = 0.0044), and GLCM Dissimilarity (p = 0.0063). At multivariate analysis, only GLCM Entropy-log₁₀ was retained in the model (χ² = 7.7120, p = 0.0055). Kaplan–Meier curves showed that patients with GLCM Entropy-log₁₀ >1.28 had a significantly better OS than patients with GLCM Entropy-log₁₀ ≤1.28 (χ² = 10.6063, p = 0.0011). Conclusions: Texture analysis of 68Ga-DOTATOC PET/CT images, by revealing the heterogeneity of somatostatin receptor expression, can predict the clinical outcome of NET patients. Full article

(1) Background: GEP-NETs are frequently diagnosed at advanced stage. For well-differentiated somatostatin receptor-positive (SSTR+) NETs, SSA are the preferred first-line therapy. However, in newly diagnosed patients with G2/G3 and a high tumor burden, SSA alone might not be enough; (2) Methods: We conducted a retrospective analysis to assess the effectiveness of combining oxaliplatin–fluoropyrimidine chemotherapy with SSA as an upfront strategy in newly diagnosed metastatic G2/G3 GEP-NET patients treated with oxaliplatin–fluoropyrimidine-based chemotherapy; (3) Results: Between March 2017 and October 2023, 32 pts (19 males, 13 females; M:F = 1.5:1; median age 54 years, range 31–82) were deemed eligible to receive oxaliplatin–fluoropyrimidine chemotherapy in addition to SSA; 14 received XELOX and 18 FOLFOX. After a median follow-up of 26 mo., each patient had completed at least two cycles of chemotherapy. The ORR was 25%, with a median DoR of 21.3 mo. The DCR was 87.5%. Notably, 28.1% of patients experienced tumor shrinkage sufficient for radical surgery on residual tumor lesions, encompassing both primary tumors and metastases; (4) Conclusions: Upfront treatment with the combination of oxaliplatin–fluoropyrimidine and SSA demonstrated effectiveness and safety. This approach may be considered to facilitate conversion surgery in eligible patients. Full article

Neuroendocrine neoplasms (NENs) comprise a heterogeneous tumor group arising from neuroendocrine cells, commonly originating in the gastroenteropancreatic tract and bronchopulmonary system. Their incidence has risen significantly, owing to improved diagnostic techniques and increased clinical recognition. While previous reviews have explored the molecular and genetic basis of NENs, limited attention has been given to the role of epigenetic modifications, particularly DNA methylation, in tumorigenesis and disease progression. This review focuses on lung, pancreas, and thyroid well-differentiated neuroendocrine tumors (NETs), highlighting epigenetic mechanisms, particularly DNA methylation, as promising biomarkers for early diagnosis and risk stratification. Aberrant DNA methylation can silence key tumor suppressor genes, including RASSF1A and CDKN2A, thereby promoting tumorigenesis. Integrating DNA methylation profiles with conventional biomarkers such as chromogranin A (CgA) may enhance diagnostic accuracy and inform therapeutic strategies. Emerging epigenetic therapies offer potential avenues for personalized treatment based on molecular profiling. Unlike prior reviews that broadly cover genetic and epigenetic changes in NENs, this review uniquely emphasizes the translational potential of epigenetic biomarkers in clinical practice. By synthesizing recent findings and evaluating their clinical implications, we aim to bridge the gap between molecular research and practical applications in diagnosis, prognosis, and therapy. Full article

Background/Objectives: Neuroendocrine tumors (NETs) can arise in any organ and are most commonly found in the lungs and gastroenteropancreatic (GEP) system. GEP-NETs represent a small percentage of gastrointestinal cancers, and therefore, the standard treatment is not well-defined, especially for advanced disease. Our objective is to review GI NETs among veterans and analyze their therapeutic outcomes. Methods: A total of 61 GI NET cases were identified from our institution from 2019–2024. In total, twenty-seven review papers, ten population-based/multicenter/outcome studies, six case reports, and one case series were reviewed for the literature review. Results: The incidence of GI NETs at our institution was higher than the known epidemiology of GI NETs. Small intestine NETs were one of the most common sites of GEP-NETs at our institution, with only one of nineteen cases being grade 3 poorly differentiated neuroendocrine carcinoma. All cases of colonic and rectal NETs had good clinical outcomes consistent with findings from the literature. Most of the gastric NETs were type 1 and had benign courses of disease, except for one case with an intermediate grade and metastatic liver lesions. One case of esophageal neuroendocrine carcinoma (E-NEC) showed a complete response to chemotherapy despite a significant tumor burden on presentation and high-grade pathology, while another case of ENEC had recurrent disease despite systemic therapy. Conclusions: While the role of surgery or endoscopic resection is limited to localized tumors, combined treatment with chemoradiation can significantly improve patient outcomes, especially in high-grade, poorly differentiated tumors. Further studies are needed to establish systemic (i.e., chemotherapy and radiation) treatment strategies for poorly differentiated GI NETs. Full article

The Eastern Canadian Gastrointestinal Cancer Consensus Conference was an annual meeting that was held in St. John’s, Newfoundland and Labrador, from 26 to 28 September 2024. This included experts in medical oncology, radiation oncology, surgical oncology, nuclear medicine, and general practitioners in oncology (GPO) from across the eastern Canadian provinces who are involved in the management of patients with gastrointestinal malignancies. This consensus statement generated by the conference addresses multiple topics, including the management of localized rectal cancer, liver-limited colorectal cancer, systemic therapy for advanced biliary tract cancers, radioligand therapy for gastroenteropancreatic neuroendocrine tumors (GEP-NETs), systemic therapy for pancreatic and midgut well-differentiated NETs, and systemic therapy for HER2-positive gastroesophageal cancers. Full article

Background and Objectives: At diagnosis, the initial staging of well-differentiated neuroendocrine tumors (WD NETs) aids in treatment planning. The somatostatin receptor (SSTR)-PET has been recommended for staging of WD NETs although limited data are available on its impact on non-gastroeneteropancreatic (GEP) NETs. The main purpose of this study was to compare the stage migration after the addition of SSTR-PET to the workup of patients at the initial staging of GEP NETs to those with non-GEP NETs, and its potential impact on patient management. Methods: This prospective study included patients with WD NETs at initial staging. Demographic data, results of conventional and SSTR-PET staging, and SUVmax were recorded. Three panels of experts assessed the potential impact of SSTR-PET to management. Results: There were 482 patients, including 376 with gastroenteropancreatic (GEP) NETs and 106 non-GEP NETs with a median SUVmax of 34.7 [Q1, Q3: 22.8, 59.1]) and 19.0 [Q1, Q3: 7.9, 39.8]), respectively; p < 0.001. The discordant M-stage was recorded in 111/473 patients (23.5%). PET suggested a higher stage in 78/369 GEP NETs (21.1%), including the detection of extrahepatic metastatic disease in 42/114 (36.8%) patients with liver metastases only on CI. For non-GEP NETs, PET suggested a higher stage in 10/104 (9.6%) and CI suggested a higher stage in 15/104 (14.4%), with CI detecting liver metastases more frequently. The potential impact to management for patients with discordant M-stage was scored as moderate to high between 57/101 (56.4%) and 79/101 (78.2%) of patients. Conclusions: One in five patients are upstaged following SSTR-PET, more frequently with GEP NETs than others. SSTR-PET identifies extrahepatic metastatic disease in >1/3 of patients with presumed liver-only metastases on CI. Stage migration following SSTR-PET may result in frequent moderate or significant management change. Full article

Background: Gastro-entero-pancreatic neuroendocrine tumors (GEP-NETs) are the most prevalent subgroup among NETs and include heterogeneous tumors characterized by different clinical behavior and prognosis. The NETest is a tool based on real-time PCR combined with deep learning strategies to specifically identify tumors with a neuroendocrine genotype. Despite the promising results achieved regarding its utility in the field of GEP-NETs, the NETest has not yet entered into routine clinical practice. Methods: We performed a systematic review aimed at summarizing available evidence on the application of the NETest in both the diagnosis and the prognostic stratification of GEP-NETs. Results: We identified five studies evaluating the diagnostic role of the NETest and nine studies evaluating its prognostic value. The NETest emerged as a reliable biomarker for GEP-NET diagnosis with an accuracy higher than 90%, regardless of tumor stage and grade. However, according to some studies, the NETest showed a low specificity, mainly attributed to interferences with other gastro-intestinal malignancies. In terms of prognostic value, the NETest correlated with the detection of residual disease after surgery in six studies. The NETest was also associated with patients’ survival outcomes, namely progression-free survival (PFS) and overall survival (OS) in three studies. Conclusions: According to current systematic review, the value of the NETest both for diagnosis and for prognosis of GEP-NET emerged as robust across different studies. Further prospective analysis on larger GEP-NET series is encouraged to validate this tool, improving patients’ diagnosis, management, and follow-up. Full article

Background: Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) are rare tumors originating from neuroendocrine cells in the gastroenteropancreatic system. They are increasingly recognized as being potentially associated with chronic intestinal inflammatory conditions, namely Crohn’s disease and ulcerative colitis. Celiac disease (CD) is an immune-mediated chronic gastrointestinal inflammation triggered by gluten in genetically predisposed individuals. This study aimed to explore the relationship between GEP-NENs and CD, providing a detailed review of the existing literature and addressing the (possible) gaps in current knowledge. Methods: We conducted an extensive search of international databases using relevant keywords, with the last update on 1 November 2024. A total of 19 studies, published between 1983 and 2024, were included: two prospective studies, five retrospective studies, and 12 case reports. Results: Overall, we included 107 GEP-NENs in our analysis. Among the 94 GEP-NENs identified in prospective and retrospective studies, the small intestine was the most common site (88.3%). The small intestine was also the most frequently reported site in the case report series (46.2%), accounting for 13 GEP-NENs in 12 patients with CD. Conclusions: Although most studies on the association between CD and GEP-NENs are heterogeneous, and while some lack crucial data, emerging evidence suggests that screening GEP-NEN patients for CD could offer valuable insights. Testing for the presence of CD might reveal whether the observed association is more than coincidental and possibly pave the way for exploring and understanding the role of chronic inflammation in the tumorigenesis of GEP-NENs in CD. Full article

Background/Objectives: Neuroendocrine tumors (NETs) are heterogeneous malignancies arising from enterochromaffin cells that can arise from the gastrointestinal (GI) tract and pancreas. Surgical management is the cornerstone of treatment, with the optimal approach tailored by tumor grade, size, location, and presence of metastasis. This review discusses the current strategies for the surgical management of NETs of the gastroenteropancreatic tract. Methods: A review of the available literature was conducted to evaluate surgical approaches to NETs. Consensus guidelines were incorporated to synthesize evidence-based recommendations. Results: For gastric NETs, surgical approach depends on Rindi Classification, WHO grade, and tumor size, with endoscopic approaches favored for smaller and low-grade lesions. Small bowel NETs can be multifocal and thus often require a surgical approach with careful evaluation of the entire intestine. Pancreatic NETs are categorized as functional or non-functional, with enucleation or formal resection strategies based on size, location, functional status, and risk of malignancy. Colorectal NETs are primarily treated with transanal localized or formal surgical resection, depending on lesion size and depth of invasion or presence of lymph node involvement. Appendiceal NETs are either treated with appendectomy or right hemicolectomy, depending on the size, location, and invasiveness of the lesions. For metastatic NETs, cytoreduction, liver transplantation, and targeted therapies offer symptom relief and possible survival benefits. Conclusions: Surgical resection provides curative potential for localized NETs and symptom control in metastatic cases. Future research is essential to refine guidelines for intermediate-risk lesions and multifocal tumors, ensuring optimal outcomes for patients with gastroenteropancreatic NETs. Full article