Overview of the 2022 WHO Classification of Neuroendocrine Neoplasms

Approaching Gallium-68 radiopharmaceuticals for tumor diagnosis: a Medicinal Chemist's perspective

Nuclear medicine has revolutionized disease diagnosis and treatment, particularly in oncology, by enabling precise imaging and targeted therapies using radiopharmaceuticals. Recently, Gallium-68 (68Ga) has emerged as a powerful positron emission tomography (PET) imaging agent, with a growing role in theranostics when paired with 177Lu for cancer treatment. The ability to obtain 68Ga from 68Ge/68Ga generators, along with its favorable radiochemical and pharmacokinetic properties, has driven an increasing number of clinical applications, which culminated with the approvals of 68Ga-DOTA-TOC and 68Ga-DOTA-TATE for the treatment of neuroendocrine tumors, and 68Ga-PSMA-11 for prostate cancer over the past decade. This review provides a comprehensive overview of 68Ga radiochemistry, chelators, and key compounds in clinical trials, highlighting the potential of this radionuclide in precision oncology.

Pancreato-hepatobiliary neuroendocrine tumors diagnosed through endoscopic ultrasound: Clinical characteristics and factors associated with high-grade lesions

BACKGROUND

Neuroendocrine tumors (NETs) are an important type of neoplastic disease of the digestive tract. There is little data on NETs originating from the pancreato-hepatobiliary region of the digestive tract in Pakistan.

AIM

To evaluate different types of pancreato-hepatobiliary NETs (PHB-NET) diagnosed with endoscopic ultrasound (EUS) and to identify factors associated with high-grade NETs.

METHODS

All patients diagnosed with PHB-NET through EUS-guided biopsy were included in the study. The site of origin, histology, and grade of PHB-NETs were noted and factors associated with high-grade lesions were analyzed. SPSS, version 20.0 was used for statistical analysis.

RESULTS

A total of 36 patients with PHB-NET were included. Males and females were equal in numbers, i.e., 18 (50%) each. The mean age was 48 ± 15.7 years with an age range of 17-70 years. The most common sites of origin of PHB-NET were: Pancreas 20 (55.6%), porta hepatis mass 8 (22.2%), perigastric mass 3 (8.3%) and others 5 (13.9%). The mean size of the PHB-NETs was 34.7 ± 22.5 mm. Among pancreatic NETs, the most commonly affected areas were body 9, tail 5, and head 5. Only 4 (11.1%) PHB-NETs were functioning, all of which were insulinomas originating from the body or tail of the pancreas. Two-thirds of PHB-NETs, 24 (66.6%), were benign (WHO grade I: 19; grade 2: 5) while one-third 12 (33.3%) were neuroendocrine cancers (NEC) (WHO grade III). Histological types were large cell 17 (47.2%), small cell 8 (22.2%), mixed 1 (2.8%), and undetermined 10 (27.8%). Factors associated with NECs were age > 40 years (P = 0.016), extra-pancreatic origin of the lesion (P = 0.014), and small cell histologic type (P < 0.001).

CONCLUSION

The most common site of PHB-NET detected through EUS was the pancreas. Although most were benign, about one-third were high-grade cancers. Insulinoma was the most common functioning tumor. NECs were associated with advanced age, extra-pancreatic origin, and small-cell histology.

Management paradigm for ovarian neuroendocrine carcinoma: a systematic review

INTRODUCTION

Neuroendocrine neoplasms (NENs) of the female genital tract are rare, comprising only 1-2% of gynecologic tumors, with ovarian neuroendocrine carcinoma (O-NEC) accounting for less than 1% of all ovarian cancers. Despite its rarity, O-NEC is a highly aggressive tumor with poor prognosis and significant diagnostic complexity, warranting focused clinical attention and demand greater awareness to improve diagnostic and therapeutic strategies.

METHODS

This systematic review analyzed management paradigm for O-NEC through a comprehensive search on the databases PubMed, Science Direct, Wiley, Springer Link, Google Scholar and Cochrane Central Register of Controlled Trials that was performed on August 1st, 2024.

RESULTS

A comprehensive search on August 1st, 2024, identified 21 eligible studies (6 retrospective cohorts, 12 case reports, 3 case series), encompassing 923 cases of O-NEC. The most common subtypes were small-cell (40%) and large-cell (39.8%) NEC. Most patients presented with advanced-stage (Stage III-IV: 52%). Immunohistochemical markers included synaptophysin (84%), chromogranin A (64.2%), CD56 (69%), and NSE (77.7%). Treatment varied from surgery alone (35%) or surgery plus chemotherapy (32%) being most common. No standardized regimen of chemotherapy was identified with etoposide/cisplatin and paclitaxel/carboplatin were most frequently used. Survival outcomes were poor, with median overall survival ranging from 11 to 23.5 months. The stage at diagnosis was a crucial prognostic factor.

CONCLUSIONS

The O-NEC is a rare, heterogeneous malignancy with diverse histopathology, variable immunohistochemical profiles, and generally poor prognosis. Early-stage disease may be managed with surgery alone, while advanced stages require multimodal treatment including surgery with adjuvant platinum-based chemotherapy. Due to limited cases and predominantly retrospective data, standardized diagnostic and treatment protocols are lacking. Prospective multicenter studies and centralized registries are needed to improve understanding and patient outcomes.

Transarterial radioembolization in neuroendocrine liver metastases 25 years later: A systematic review

Transarterial Radioembolization (TARE) currently lacks a defined role in treating neuroendocrine liver metastases (NELM). This systematic review aims to clarify TARE's role based on its prognostic impact. A search identified 138 studies onPubMed/MEDLINE over the past 25 years, focusing on TARE for NELM patients. Of these, 46 studies met eligibility criteria, and 11 were selected for their similar settings, populations, and outcomes. These were grouped into three clusters based on survival outcomes: overall survival (OS), hepatic progression-free survival (HPFS), and imaging response (IR) per RECIST 1.1 criteria. Statistical analyses showed a median OS of 33 months for 809 patients, a median HPFS of 24 months for 414 patients, and an IR of 28.6 % complete or partial response, 57.8 % stable disease, and 13.6 % disease progression in 581 patients. This evidence supports TARE as a viable treatment option, but further studies are needed to optimize its use and dosimetric procedures.

One-day dual-tracer examination in neuroendocrine neoplasms: a real advantage of low activity LAFOV PET imaging

PURPOSE

Somatostatin receptor (SSTR)-PET is crucial for effective treatment stratification of neuroendocrine neoplasms (NENs). In highly proliferating or poorly differentiated NENs, dual-tracer approaches using additional [18F]FDG PET can effectively identify SSTR-negative disease, usually requiring separate imaging sessions. We evaluated the feasibility of a one-day dual-tracer imaging protocol with a low activity [18F]FDG PET followed by an SSTR-PET using the recently introduced [18F]SiFAlin-TATE tracer in a long axial field-of-view (LAFOV) PET/CT scanner and its implications in patient management.

METHODS

Twenty NEN patients were included in this study. Initially, a low activity [18F]FDG PET was performed (0.5 ± 0.01 MBq/kg; PET scan 60 min p.i.). After 4.2 ± 0.09 h after completion of the [18F]FDG PET, a standard activity of [18F]SiFAlin-TATE was administered (3.0 MBq/kg; PET scan 90 min p.i.). To ensure the quantification accuracy of the second scan, we evaluated the potential impact of residual [18F]FDG activity by segmenting organs with minimal physiological SSTR-tracer uptake, such as the brain and myocardium, and assessing the activity concentrations (ACTs) of tumor lesions. Residual tumor lesion ACTs of [18F]FDG were calculated by factoring fluorine-18 decay, identifying a maximum residual ACT of 15% (R15%). To account for increased [18F]FDG trapping over time, higher residual ACTs of 20% (R20%) were considered. These simulated [18F]FDG ACTs were compared with those measured in the second PET scan with [18F]SiFAlin-TATE. The influence of the dual-tracer PET/CT results on therapeutic strategies was evaluated.

RESULTS

[18F]FDG cerebral uptake significantly decreased in the subsequent SSTR-PET (mean uptake [18F]FDG: SUVmean 6.0 ± 0.4; mean uptake in [18F]SiFAlin-TATE PET: SUVmean 0.2 ± 0.01; p < 0.0001); with similar results recorded for the myocardium. Simulated residual [18F]FDG ACTs represented only a minimal percentage of ACTs measured in the tumor lesions from the second PET scan (R15%: mean 5.2 ± 0.9% and R20%: mean 6.8 ± 1.2%), indicating only minimal residual activity of [18F]FDG that might interfere with the second PET scan using [18F]SiFAlin-TATE and preserved semi-quantification of the latter. Dual-tracer PET/CT findings directly influenced changes in therapy plans in eleven (55%) of the examined patients.

CONCLUSION

LAFOV PET scanners enable a one-day dual-tracer protocol, providing diagnostic image quality while preserving the semi-quantification of two 18F-labeled radiotracers, potentially simplifying the assessment of tumor biology and improving the clinical patient management while reducing logistical challenges. Additionally, low-activity PET imaging facilitates one-day dual-tracer PET examinations.

Non-hypervascular pancreatic neuroendocrine neoplasms differentiation from CA19-9 negative pancreatic ductal adenocarcinomas based on contrast CT: A large sample series

PROPOSE

This study aims to evaluate the effectiveness of contrast-enhanced computed tomography (CT) in distinguishing non-hypervascular pancreatic neuroendocrine neoplasms (PNENs) from pancreatic ductal adenocarcinomas (PDACs) with a normal serum level of carbohydrate antigen 19-9 (CA19-9) levels.

METHODS

This retrospective study included 134 patients with pathologically confirmed non-hypervascular PNENs and 128 patients with CA19-9-negative PDACs, all of whom underwent contrast-enhanced CT prior to surgery between January 2015 and March 2024. Following independent evaluation by two radiologists, qualitative features from both groups were extracted in the arterial and portal venous phase and subsequently compared using univariate and multivariate analysis.

RESULTS

Patients with CA19-9 negative PDACs were significantly older than those with non-hypervascular PNENs (p < 0.001), and the majority of PDACs were located in the head of the pancreas (p < 0.01).Univariate analysis showed that non-hypervascular PNENs exhibited a higher frequency of well-defined tumor margins (p < 0.001) and calcification (p = 0.032) and a lower frequency of local invasion (p < 0.001), peripancreatic vascular invasion (p = 0.001), intra- or extrahepatic bile duct dilatation (p < 0.001), distal main pancreatic duct dilatation (p < 0.001), regional lymphadenopathy (p < 0.001) and tumor homogeneity (p < 0.001) when compared to CA19-9 negative PDACs. Multivariate analysis identified the absence of local invasion (Odds Ratio (OR) = 0.233; 95 % Confidence Internals (95 % CI):0.114-0.476; p < 0.001), absence of peripancreatic vascular invasion (OR = 0.434; 95 % CI:0.217-0.870; p = 0.019), a normal distal main pancreatic duct diameter (OR = 0.398; 95 % CI:0.202-0.785; p = 0.008), absence of regional lymphadenopathy (OR = 0.455; 95 % CI:0.238-0.870; p = 0.017) and tumor heterogeneity (OR = 0.240; 95 % CI:0.126-0.456; p < 0.001) as significant predictors of non-hypervascular PNENs. The area under the receiver operating characteristic curve for the radiological feature model was 0.829 based on logistic regression.

CONCLUSIONS

Qualitative features in contrast-enhanced CT images could be beneficial in differentially diagnosing non-hypervascular PNENs and CA19-9 negative PDACs.

Locally advanced pheochromocytoma/paraganglioma exhibit high metastatic recurrence and disease specific mortality rates: long-term follow-up of 283 patients

IMPORTANCE

Data on locally advanced (LAP) pheochromocytoma/paraganglioma (PPGL), based on capsular, vascular or periadrenal fat invasion, tumor emboli and extra-adrenal extension, are scarce.

OBJECTIVE

To compare outcomes of patients with LAP and without (nLAP).

DESIGN

Retrospective cohort study, 1981-2024, prospectively supplemented 2020-2024.

SETTING

Referral center.

OUTCOMES

Overall, metastatic and nonmetastatic recurrence, overall (OAS) and disease-specific survival (DSS).

RESULTS

Of 283 patients followed for 11.3 ± 8.8 (mean ± SD) years, 79 (27.9%) had LAP. Compared to patients with nLAP (n = 204), patients with LAP had more overall (n = 17 vs. 31, hazard ratio 2.4, 95% CI 1.4-5.0) and metastatic (11 vs. 9, HR 6.8, 2.2-20.6) and similar (6 vs. 22, HR 1.2, 0.5-3.0) nonmetastatic recurrences. OAS was comparable (12 vs. 42 nonsurvivors, HR 1.2, 0.6-2.3), but mortality from metastatic disease was higher with LAP (2 vs. 4 deaths, HR 12.2, 1.8-82.8). Extra-adrenal tumor location was predictive of metastatic and nonmetastatic recurrence but not of OAS or DSS, tumor size of metastatic recurrence and of DSS, cluster 1 and 2 pathogenic variants of overall and nonmetastatic recurrence but not of OAS or DSS. LAP with tumor emboli and extra-adrenal extension predicted overall (HR 4.5, 1.3-14.2 and 5.0, 1.4-13.7) and metastatic recurrence (HR 24.6, 6.4-91.8 and 6.5, 1.6-23.4), OAS (HR 21.2, 2.8-108, tumor emboli only) and DSS (HR 22.6, 3.5-183 and 13.1, 1.7-120), LAP with vessel invasion nonmetastatic recurrence (HR 3.6, 1.2-10.0).

CONCLUSION

Patients with LAP vs. nLAP have higher metastatic recurrences and worse DSS. Tumor emboli and extra-adrenal extension indicated lower DSS, warranting a close follow-up.

Transcriptomic analysis of transformed small-cell lung cancer from EGFR-mutated lung adenocarcinoma reveals distinct subgroups and precision therapy opportunities

BACKGROUND

Small-cell lung cancer (SCLC) transformation is one of the major mechanisms of resistance to Epidermal Growth Factor Receptor tyrosine kinase inhibitors (EGFR-TKIs). Chemotherapy is typically the recommended treatment for transformed SCLC (T-SCLC), similar to primary SCLC. However, the benefits of chemotherapy alone are minimal. Prior research highlights differences between the biological traits of T-SCLC and primary SCLC or EGFR-mutated lung adenocarcinoma (LUAD). This study aims to elucidate the molecular characteristics of T-SCLC and identify potential treatment modalities.

METHODS

We retrospectively collected tissue samples from LUAD, T-SCLC post-EGFR-TKI resistance, and primary SCLC. Genomics, transcriptomics, and proteomics were performed to clarify the differences between T-SCLC, LUAD, and primary SCLC. Hierarchical clustering analysis was then used to categorize the molecular subtype of T-SCLC, followed by a survival analysis based on these subtypes.

RESULTS

A study involving 61 patients investigated differences between LUAD, SCLC, and primary SCLC. RNA sequencing revealed distinct gene expression variations, particularly up-regulation in PPM1E, INSM1, and KCNC1 genes in T-SCLC. Pathway analysis linked T-SCLC to the cell cycle and neural differentiation. By conducting Hierarchical clustering analysis on RNA-seq data, the entire population can be categorized into two distinct groups. While certain T-SCLC showed similarities and differences compared to SCLC, with subtypes: LUAD-like and Non-LUAD-like. Notably, the LUAD-like subtype had significantly higher NKX2-1 expression (mean 371.8 vs. 41.8, P < 0.0001). T-SCLC treatment approaches were categorized into matched and unmatched groups, delineated by the alignment of specific therapies with corresponding pathologies. The matched group (13 cases) exhibited a significantly prolonged median progression-free survival compared to the unmatched group (10 cases) (5.4 months vs. 3.6 months, P = 0.02).

CONCLUSIONS

T-SCLC exhibits marked molecular distinctiveness, setting it apart not only from LUAD but also from classical SCLC. This distinction extends to its classification into two discernible molecular subtypes: LUAD-like and Non-LUAD-like. Customizing therapeutic protocols to align with these specific subtypes have the potential to identify the most appropriate treatment for T-SCLC.

Novel framework for response evaluation criteria in grade 1/2 neuroendocrine tumors (RECIN) following [177Lu]Lu-DOTATATE therapy: post-hoc analysis of the phase 2 LuCAP trial

PURPOSE

Treatment response assessment in grade 1/2 neuroendocrine tumors (NETs) has been a key challenge due to their indolent nature. Here, we propose the novel response evaluation criteria with [68Ga]Ga-somatostatin analogue (SSA)-PET/CT in grade 1/2 NETs (RECIN) following [177Lu]Lu-DOTATATE therapy and evaluate its survival impact vis-à-vis conventional radiographic response assessment.

METHODS

This was a post-hoc analysis of the phase 2 LuCAP trial, wherein somatostatin receptor-positive, advanced grade 1/2 gastroenteropancreatic NET patients were treated with [177Lu]Lu-DOTATATE ± capecitabine. Tumor response assessment was done with serial [68Ga]Ga-DOTANOC-PET/CECT. Up to five target lesions were evaluated according to Response Evaluation Criteria in Solid Tumors (RECIST 1.1) for radiographic response. Summed SULpeak of maximum five hottest lesions were evaluated for molecular response. Associations with progression-free survival (PFS) were evaluated using hazard ratios (HRs) and their 95% confidence intervals (95%CIs) along with Harrell's C-index.

RESULTS

Seventy-two patients were included with 23/72 (32%) patients achieving RECIST-partial response (PR). The novel RECIN-PR was defined as ≥ 25% decrease in summed SULpeak or conventional RECIST-PR with no signs of radiographic progression. Based on this, 40/72 (56%) patients achieved RECIN-PR. In particular, of the 42 patients with RECIST-stable disease, 17 (40%) had RECIN-PR. RECIN-PR was associated with significantly better PFS (HR: 0.33, 95%CI: 0.15-0.76; C-index: 0.67) and had better predictive ability compared to RECIST-PR (HR: 0.52, 95%CI: 0.21-1.29; C-index: 0.60).

CONCLUSION

In advanced grade 1/2 NETs treated with [177Lu]Lu-DOTATATE, [68Ga]Ga-SSA-PET/CT-based novel RECIN framework proved superior to conventional radiographic response assessment in terms of early response detection in indolent disease and better predictive ability.

CLINICAL TRIAL REGISTRATION

Clinical Trials Registry-India, CTRI/2020/01/022636.

Genes of the "regulation of lymphocyte activation" pathway may influence immune cells infiltration in growth hormone secreting pituitary tumors

PURPOSE

The tumor microenvironment (TME) may provide a useful framework for understanding the heterogeneous behavior of growth hormone (GH) secreting pituitary adenomas. Although the interest in TME in somatotropinomas has increased exponentially over the last few decades, there is limited elucidation of its mechanisms, particularly in relation to genes expression involved in its regulation.

METHODS

A retrospective, observational, single-center study was conducted on 85 subjects: 46 patients diagnosed with acromegaly and 39 controls. After DNA extraction, clinical exome sequencing was performed and genomic alterations were detected, classified, and filtered using a dedicated bioinformatics pipeline.

RESULTS

5759 unique genetic variants were found in patients with acromegaly. 33 patients (72%) showed the presence of at least one pathogenic variant in at least one of the following genes: FANCD2, SPTA1, TYRO3, and ZNF335. The enrichment pathway analysis of mutated genes was performed and showed that these genes were included in the same genetic pathway called "regulation of lymphocyte activation" (GO:0051249). Inflammatory infiltrate was analyzed in histological samples in 26 patients. A significantly higher number of CD68 + macrophages (P-value = 0.008), a lower number of CD8 + T lymphocytes (P-value = 0.037) and a higher CD68 + macrophages/ CD8 + T-lymphocytes ratio (P-value = 0.004) were observed in patients with pathogenic variants of genes of "regulation of lymphocyte activation" pathway.

CONCLUSION

This study provides new insights into the genetic basis of the TME in somatotropinomas and suggests that genetics may influence immune cells infiltration in acromegaly.

Last decade of advances in gastric neuroendocrine tumors: Innovations, challenges, and future directions

BACKGROUND

Gastric neuroendocrine tumors (G-NETs) are rare tumors originating from enterochromaffin-like cells, with an incidence of 0.4 per 100000 annually. There are three main types: (1) Type I, linked to chronic atrophic gastritis and hypergastrinemia, makes up 75%–80% of G-NETs; (2) Type II, associated with Zollinger-Ellison syndrome (ZES) and multiple endocrine neoplasia, comprises 5%; and (3) Type III, sporadic tumors with a higher metastatic potential, accounting for 15%–25%. Diagnosis involves endoscopy, biopsy, and histological examination. Additional methods include serum gastrin testing, immunohistochemistry, and imaging techniques such as computer tomography or magnetic resonance imaging for detecting metastasis. Type I treatment usually involves endoscopic resection (ER), with surgical resection for recurrence. Somatostatin analogs (SSAs) can reduce tumor size, and the prognosis is generally excellent. Type II treatment centers on surgical removal of the gastrinoma, with ER for smaller lesions and SSAs for symptom management. Type III requires surgical resection (partial or total gastrectomy) with lymph node dissection, and possibly chemotherapy. This type has a worse prognosis due to its aggressive nature. Emerging treatments like Peptide Receptor Radionuclide Therapy are promising for advanced cases, and ongoing research into immunotherapies is expanding future treatment options. Regular endoscopic follow-up is crucial to monitor for recurrence or metastasis across all types. Our literature review explores the current perspectives on G-NETs and highlights the importance of further research to improve diagnostic precision and treatment, particularly for those associated with less favorable cases.

AIM

To improve diagnostic precision and treatment, particularly for those associated with less favorable cases.

METHODS

A systematic search was conducted in PubMed, Scopus, and Web of Science until September 2024. Two independent reviewers screened titles, abstracts, and full texts for eligibility based on G-NET treatment in adults. Eligible studies included cohort studies, clinical trials, case series, and case reports, while in vitro, pediatric, and non-English studies were excluded. Relevant data were extracted independently, and disagreements were resolved through discussion. Study quality was assessed using appropriate tools.

RESULTS

G-NETs are rare, classified into three types: (1) Type I; (2) Type II; and (3) Type III. Type I G-NETs, often associated with chronic atrophic gastritis, are typically slow-growing and low-grade, with favorable outcomes following surgical resection. Type II G-NETs arise in hypergastrinemia conditions like multiple endocrine neoplasia and ZES, showing moderate malignancy risk. Type III G-NETs, the most aggressive and least common, present with distant metastases and poor prognosis. Diagnosis relies on endoscopy, imaging, and biomarkers like chromogranin A. Treatment varies by type, ranging from ER to aggressive surgery and chemotherapy for advanced cases. Regular follow-up is essential to monitor recurrence, particularly for type III G-NETs.

CONCLUSION

G-NETs require tailored diagnosis and treatment based on type and stage. Types I and II generally have better prognosis, while types III and IV are linked to poorer outcomes due to invasion and metastasis. Treatment strategies vary from ER for type I to extensive surgery for type III. Emerging therapies, like somatostatin analogs and peptide-receptor radionuclide therapies, show promise in advanced cases. Further research is essential to improve early diagnosis and treatment, particularly for high-risk lesions.

Near-Infrared Photoimmunotherapy in Brain Tumors-An Unexplored Frontier

Near-infrared photoimmunotherapy (NIR-PIT) is a promising cancer treatment that uses near-infrared light to activate a conjugate of a monoclonal antibody (mAb) and a photoactivatable silica phthalocyanine dye (IRDye700DX: IR700). Unlike conventional photodynamic therapy (PDT), NIR-PIT selectively destroys targeted tumor cells while preserving the surrounding normal tissue and providing superior tissue penetration. Recently, NIR-PIT has been approved for the treatment of unresectable recurrent head and neck cancers in Japan. It induces highly selective cancer cell death; therefore, it is expected to be a new curative treatment option for various cancers, including brain tumors. In this review, we compare the principles of NIR-PIT and PDT and discuss the potential applications of NIR-PIT for brain tumors. We selected targetable proteins across various types of brain tumors and devised a strategy to effectively pass the mAb-IR700 conjugate through the blood-brain barrier (BBB), which is a significant challenge for NIR-PIT in treating brain tumors. Innovative approaches for delivering the mAb-IR700 conjugate across the BBB include exosomes, nanoparticle-based systems, and cell-penetrating peptides. Small-molecule compounds, such as affibodies, are anticipated to rapidly accumulate in tumors within intracranial models, and our preliminary experiments demonstrated rapid uptake. NIR-PIT also induces immunogenic cell death and activates the anti-tumor immune response. Overall, NIR-PIT is a promising approach for treating brain tumors. It has the potential to overcome the limitations of conventional therapies and offers new hope to patients with brain tumors.

Molecular Imaging for Response Assessment of Neuroendocrine Tumors (NET)

Assessing treatment response in neuroendocrine tumors (NET) remains a significant challenge due to their typically indolent growth and heterogenity, the frequent occurrence of disease stabilization rather than tumor shrinkage after therapy, and the inherent limitations of conventional imaging criteria. While molecular imaging-primarily somatostatin receptor (SST) PET/CT-has improved lesion detection, the absence of standardized response criteria limits its clinical utility and prevents its use as full replacement of conventional imaging. Emerging strategies, including revised thresholds for dimensional changes, criteria evaluating different features, such as lesions' density and functional tumor volumes, offer potential improvements in response evaluation but require further validation for routine clinical implementation. This review examines the current challenges in assessing NET treatment response, evaluates the strengths and limitations of available imaging modalities, and discusses emerging approaches and future directions for optimizing therapeutic monitoring in the heterogeneous panorama of NET.

Survival Benefits of GLP-1 Receptor Agonists in Patients with Neuroendocrine Neoplasms: A Large-Scale Propensity-Matched Cohort Study

Background: Neuroendocrine neoplasms (NENs) represent a heterogeneous group of malignancies that consist of two major subtypes: neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs). Glucagon-like peptide-1 receptor agonists (GLP-1Ra) have demonstrated favorable results in preclinical studies, but their impact on NEN outcomes remains unexplored. Methods: Using the TriNetX US Research Network, we identified adult patients with NEN and either diabetes or obesity. After 1:1 propensity score matching based on demographics, comorbidities, procedures, and medication use, we compared survival outcomes between patients who received GLP-1Ra after NEN diagnosis and those who did not. Results: Among 32,464 eligible patients, 3139 received GLP-1Ra and 29,325 did not. After propensity matching, each cohort included 3043 patients with well-balanced baseline characteristics. During follow-up periods extending up to 15 years, all-cause mortality occurred in 356 (11.7%) GLP-1Ra users versus 753 (24.7%) non-users, representing a 13.0% absolute risk reduction (p < 0.001). GLP-1Ra use was associated with significantly improved survival (HR = 0.56, 95%CI = 0.49-0.63, p < 0.001). Both well-differentiated (HR = 0.52) and poorly differentiated tumors (HR = 0.56) showed significant improvement. Among primary sites, lung NENs demonstrated the most pronounced benefit (HR = 0.42). Tirzepatide showed the strongest association with reduced mortality (HR = 0.16), followed by semaglutide (HR = 0.27) and dulaglutide (HR = 0.52). Results: In this large propensity-matched study, GLP-1Ra use was associated with a 44.3% reduction in mortality risk among NEN patients with diabetes or obesity. The magnitude of the observed benefit suggests a potential role for GLP-1Ra as adjunctive therapy in this patient population. Prospective clinical trials are warranted to confirm these findings and explore underlying mechanisms.

Gastric Neuroendocrine Tumor With Pancreatic Acinar Cell Differentiation in the Background of Atrophic Gastritis: A Possible Variant of Type 1 ECL-Cell NET-A Case Report

A gastric neuroendocrine tumor (NET) with pancreatic acinar cell differentiation is extremely rare. We report the case of an 87-year-old woman with a submucosal tumor in the gastric body on a background of atrophic gastritis. She also had Sjögren's syndrome. Initially 17.8 × 6.5 mm, the tumor enlarged over 10 years, leading to wedge resection. The resected mass (45 × 40 × 30 mm) was solid with a pale yellow to gray-white cut surface. Histologically, it showed trabecular or solid nests of epithelial cells with round nuclei and eosinophilic cytoplasm. Immunohistochemistry showed positivity for CKAE1/3, VMAT2, neuroendocrine markers, and pancreatic acinar markers. Ki-67 index was 11.2%. The tumor co-expressed PDX1 and ARX and showed loss of menin and ATRX. These findings support a diagnosis of gastric ECL-cell NET G2 arising in autoimmune gastritis, with secondary pancreatic acinar differentiation. This tumor may represent a variant of type 1 gastric NET.

Upfront Oxaliplatin-Fluoropyrimidine Chemotherapy and Somatostatin Analogues in Advanced Well-Differentiated Gastro-Entero-Pancreatic Neuroendocrine Tumors

(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.

The Landmark Series: Surgical Management of Functioning and Non-Functioning Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are comparatively rare pancreatic malignancies that exhibit diverse biologic behavior, ranging from indolent tumors to widely metastatic cancers, with up to 15 % secreting hormones that cause symptoms. As a consequence, the management of PNETs is highly individualized and can include active surveillance of small (1-2 cm) and very small (< 1 cm) nonfunctioning tumors without worrisome features, parenchymal-sparing resection of appropriately located tumors, anatomic pancreatectomy and, in select cases, debulking of metastatic disease, particularly in the liver. This review synthesizes society recommendations and contemporary evidence guiding the surgical management of PNETs. Innovations in molecular profiling and systemic therapies hold promise to refine surgical algorithms for this heterogeneous tumor.

Imaging of the Small Bowel Tumors

Small bowel tumors are rare gastrointestinal tumors. Neuroendocrine tumors are the most common and demonstrate unique subtypes depending on their location. Adenocarcinomas are most common in the duodenum demonstrating luminal narrowing and irregularity. Gastrointestinal stromal tumors are heterogeneously enhancing lesions with endophytic and/or exophytic growth patterns. Immunotherapy is a unique treatment of these tumors with tumoral response best assessed with both routine computed tomography (CT) and PET/CT. Primary small bowel lymphoma has many imaging patterns, most commonly being aneurysmal dilation and thickening of the small bowel. Metastases are common and may present as polypoid lesions, focal wall thickening, or serosal deposits.

Emerging pathological diagnostic strategies for solid pseudopapillary neoplasm of the pancreas: insights from omics and innovative techniques

Solid pseudopapillary neoplasm (SPN) of the pancreas is a rare, low-grade malignant tumor, representing 0.9-2.7% of all exocrine pancreatic tumors. SPN patients generally have a favorable prognosis with a 5-year survival rate exceeding 95% following complete surgical resection. Accurate diagnosis is crucial to avoid unnecessary treatments. Currently, SPN diagnosis relies on imaging techniques such as CT and MRI, along with immunohistochemical analysis of biopsy and resection samples. The main challenge in diagnosis is the potential inability to accurately identify recurrent or metastatic SPN, as well as 'malignant' SPN, due to the lack of specific biomarkers. Advances in high-throughput omics technologies, including genomics, transcriptomics, proteomics and metabolomics, have opened new avenues for identifying novel biomarkers for SPN. Additional, liquid biopsy techniques have enabled more comprehensive analysis of biosamples such as pancreatic cyst fluid, offering promising prospects for preoperative diagnosis. This review highlights recent research on SPN diagnosis, focusing on immunohistochemical markers, tissue sampling methods and the potential of omics approaches. It also discusses the challenges and opportunities in improving diagnostic accuracy, particularly for high-grade and metastatic SPNs.

[Importance of peptide receptor radionuclide therapy for the management of neuroendocrine tumours]

Neuroendocrine tumours (NETs) are rare, heterogeneous neoplasms that often express somatostatin receptors (SSTRs). This allows targeted peptide receptor radionuclide therapy (PRRT) for NETs. PRRT is currently indicated as second- or third-line therapy for metastatic or unresectable, progressive, SSTR-positive NETs of grade (G) 1 or 2. Adequate bone marrow reserves as well as renal and hepatic function are required for PRRT. The most commonly used radiopharmaceutical for PRRT is 177Lu-DOTA-TATE. PRRT prolongs progression-free and overall survival, reduces or stabilises tumour burden, and improves tumour symptoms and quality of life. Adverse events associated with PRRT are mostly mild and transient. Haemato- and nephrotoxicity are the most common toxicities following PRRT. The NETTER‑2 and COMPOSE trials are investigating PRRT with 177Lu-DOTA-TATE/-TOC in G2 and G3 gastroenteropancreatic NETs.

Development and validation of a CT-based nomogram to preoperative prediction of pancreatic neuroendocrine tumors (pNETs) grade

BACKGROUND/PURPOSE

It is challenging to determine the pancreatic neuroendocrine tumors (pNETs) malignancy grade noninvasively. We aim to establish a CT - based diagnostic nomogram to predict the tumor grade of pNETs.

METHODS

The patients with pathologically confirmed pNETs were recruited in two centers between January 2009 and November 2020. PNETs were subdivided into three grades according to the 2017 World Health Organization classification: low-grade G1 NETs, intermediate-grade G2 NETs, and high-grade G3 NETs. The features on the CT images were carefully evaluated. To build the nomogram, multivariable logistic regression analysis was performed on the imaging features selected by LASSO to generate a combined indicator for estimating the tumor grade.

RESULTS

A total of 162 pNETs (training set n = 114, internal validation set n = 21, external validation set, n = 48) were admitted, including 73 (45.1%) G1 and 89 (54.9%) G2/3. A nomogram comprising the tumor margin, tumor size, neuroendocrine symptoms and the enhanced ratio on portal vein phase images of tumor was established to predict the malignancy grade of pNETs. The mean AUC for the nomogram was 0.848 (95% CI, 0.918-0.953). Application of the developed nomogram in the internal validation dataset still yielded good discrimination (AUC, 0.835; 95% CI, 0.915-0.954). The externally validated nomogram yielded a slightly lower AUC of 0.770 (95% CI, 0.776-0.789).

CONCLUSIONS

The nomogram model demonstrated good performance in preoperatively predicting the malignancy grade of pNETs, and can provide clinicians with a simple, practical, and non-invasive tool for personalized management of pNETs patients.

Neuroendocrine Neoplasms of the Lungs, Thyroid, and Thymus

Neuroendocrine neoplasms (NENs) comprise a group of tumours that can develop in various internal organs, but in this review, we will describe only those arising in the lungs, thyroid, and thymus. Pulmonary neuroendocrine neoplasms (pulmonary NENs) account for approximately 25% of all lung cancers. They are classified into four groups of tumours: typical carcinoids (TCs), atypical carcinoids (ACs), small cell lung carcinoma, and large cell lung carcinoma. This review focuses on TC and AC. The treatment consists mainly of radiotherapy, chemotherapy, and surgical resection, but novel drugs like atezolizumab are also utilised. The most common neuroendocrine neoplasm of the thyroid gland is medullary thyroid carcinoma (MTC), which commonly possesses RET protooncogene mutations. MTC is treated by a total thyroidectomy. Recently, tyrosine kinase inhibitors (TKIs) have emerged as an effective treatment option for patients with advanced MTC. Neuroendocrine tumours of the thymus (NETTs) are also being treated with a radical surgery.

Establishment and validation of a nomogram to predict overall survival for patients with primary renal neuroendocrine tumor

Our study aimed to develop a nomogram to predict overall survival (OS) at 1, 3, and 5 years for patients with primary renal neuroendocrine tumor (PRNET). The Surveillance, Epidemiology, and End Results database (2000-2021) was utilized to gather cases and extract data. We performed a multivariate analysis using a Cox proportional-hazards model to identify prognostic factors independently affecting OS. Based on these predictors, a nomogram was constructed and validated internally via a bootstrap resampling method. Finally, we included 266 PRNET patients. The multivariate analysis demonstrated that age, Fuhrman grade, surgery, summary stage, N stage, and histology were prognostic factors independently affecting OS (all P < 0.05). A nomogram was then constructed using the abovementioned predictors, except for the N stage. The bootstrap-corrected concordance index (C-index) of the nomogram was 0.820 (95% CI 0.805-0.835), surpassing the C-index of the TNM stage (0.571, 95% CI 0.550-0.592, P < 0.001). Based on time-dependent C-index results, the nomogram demonstrated a better discriminative ability compared to the TNM staging system. There was a good consistency between the observed values and predicted probabilities indicated by the calibration curves. The nomogram's clinical utility was supported by the decision curve analysis. Additionally, the nomogram can classify PRNET patients into low-risk and high-risk subgroups, with high-risk patients having poorer OS (P < 0.0001). The prognostic nomogram, based on individualized clinicopathological information, may be helpful in predicting survival outcomes for PRNET patients more accurately. Further external validation is required in future studies to confirm our developed nomogram's prognostic accuracy and clinical applicability.

Long-term survival after chemotherapy combined immunotherapy for recurrent mixed neuroendocrine-non-neuroendocrine neoplasms of the common bile duct

Mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) of the common bile duct (CBD) are extremely rare, with few literature reported. A 68-year-old male was admitted to our hospital with choledocholithiasis with acute cholangitis. Abdominal computed tomography showed that the CBD was occupied and clearly dilated. Consequently, the patient underwent pancreaticoduodenectomy with regional lymph node dissection. The resected tumor at the distal bile duct was 25 × 25 × 13 mm, consisting of 30% adenocarcinoma and 70% neuroendocrine carcinoma microscopically. The patient then received six cycles of adjuvant chemotherapy. Subsequently, regular monitoring of the patient's tumor marker CA19-9 showed progressive elevation. The patient was readmitted to hospital for tumor recurrence and metastasis and received palliative second-line Gemcitabine and cisplatin chemotherapy and three courses of combined immunochemotherapy (Tyvyt [Sintilimab] + Gemcitabine + Cisplatin). Throughout the treatment course, the tumor marker CA19-9 persistently remained elevated. The patient achieved an overall survival (OS) of 29 months. We found that the continuous elevation of the tumor marker CA19-9 during follow-up might suggest tumor recurrence and an unfavorable prognosis. For patients with multiple metastases of cholangiocarcinoma, combined immunotherapy could potentially assist in prolonging survival. Currently, there is no standardized treatment for biliary MiNENs, and larger scale studies are needed to establish diagnosis and treatment protocols to improve the overall survival of patients.

Impact of functionality and grading on survival in pancreatic neuroendocrine tumor patients receiving peptide receptor radionuclide therapy

Background

Peptide receptor radionuclide therapy (PRRT) is a well-established treatment option for neuroendocrine tumors (NET), yet randomized controlled trials have not provided data on its impact on overall survival. The real-world efficacy of PRRT and its association with tumor functionality and grading in pancreatic neuroendocrine tumors (PanNET) remains underexplored.

Methods

A retrospective analysis of 166 patients with histologically confirmed metastatic PanNET was performed. Subgroup analyses examined progression-free survival (PFS) and overall survival (OS) following PRRT cycles, stratified by tumor grading, tumor functionality and bone metastases.

Results

Of 166 patients, 100 (60.2%) received PRRT with a median of four cycles. In the PRRT cohort, 68% of patients had deceased. PFS after four and eight consecutive cycles was 20 and 18 months, respectively (p=0.4). OS for the entire cohort was 79 months, with patients receiving 4+ cycles of PRRT having an OS of 87 months and those receiving 5+ cycles achieving an OS of 100 months. Patients with grade 1 or 2 tumors had a significantly longer median OS of 97 months compared to 74.5 months for grade 3 tumors (p = 0.0055). There was no significant difference in OS between functioning and non-functioning tumors after PRRT. Patients with bone metastases who received PRRT had a significantly shorter OS than those without (74 vs. 89 months, p = 0.013). In 19% of patients who received PRRT, therapy was discontinued due to progressive disease, toxicity or death.

Conclusions

Patients receiving extended cycles of PRRT showed improved survival outcomes in metastatic PanNET, particularly in patients with lower tumor grades and without bone metastases. No survival difference was seen between functioning and non-functioning PanNET, while patients with grade 3 tumors and bone metastases had significantly shorter survival despite PRRT.

Endoscopic intermuscular dissection for management of 10- to 20-mm rectal neuroendocrine tumors: Pilot study (with video)

Background and study aims

Endoscopic intermuscular dissection (EID) is associated with higher rates of negative margins in treating rectal neuroendocrine tumors (R-NETs), as reported in case studies. However, evidence regarding the safety and effectiveness of EID remains insufficient. This study aimed to evaluate clinical safety and effectiveness of EID in treating 10- to 20-mm R-NETs.

Patients and methods

Retrospective clinical data from patients with 10- to 20-mm R-NETs who had undergone EID from 2019 to 2024 were collected from a tertiary hospital. The primary outcome was the histological complete resection rate and secondary outcomes included en bloc resection rate and technical success rate.

Results

Twelve patients who had undergone EID were included, with one patient excluded for pathology indicative of a leiomyoma. Among the 11 patients (mean age, 42.45 years; 72.73% males), median diameter was 11.55 mm (interquartile range 10-13 mm). All patients underwent en bloc resection and postoperative pathology confirmed negative horizontal and vertical margins, achieving a histological complete resection rate of 100%. Mean procedure time was 58.55 minutes (standard deviation [SD] 13.66 minutes) and mean postoperative hospital stay was 5.7 days (SD 1.00). One patient developed fever and another experienced abdominal pain, both of which resolved within 24 hours. There were no cases of bleeding or perforation intraoperatively or postoperatively. During a mean follow-up of 31.73 months, there were no residual tumors, local recurrences, or metastases.

Conclusions

EID is a promising treatment for 10- to 20-mm R-NETs, with high initial cure rates, and a new option for endoscopic resection. More studies of the procedure are needed.

Expression rate and comparison of immunohistochemistry biomarkers in appendiceal neuroendocrine and other epithelial cell neoplasms: Systematic review and meta-analysis

Background: Immunohistochemistry (IHC) provides comprehensive information for morphology and pathologic characteristics and is a valuable tool for establishing the correct cancer diagnosis in clinical diagnostic pathology and determining prognosis. Objectives: The current study analyzes and compares the expression of Immunohistochemistry biomarkers on neuroendocrine and epithelial cell types of appendiceal neoplasms. Design: This systematic review adhered to the recommendations in the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. We performed a meta-analysis employing a random effects model with proportions to gauge the proportion of positive cases. Method: A comprehensive systematic search in PubMed, Web of Science, and Scopus databases was conducted based on the PRISMA statement up to August 2023. Studies reporting the immunohistochemistry biomarkers expression performed in patients with primary appendiceal neuroendocrine and epithelial cell neoplasms according to the most recent World Health Organization classification of malignant tumors were included. Results: Our systematic search included 56 observational articles that meet the eligibility criteria. Meta-analysis revealed an expression rate of 93%, 91%, 87%, 71%, 94%, 99%, 32%, 76%, 25%, and 91% for non-specific enolase (NSE), chromaffin A, synaptophysin, Serotonin, SATB2, Caudal-type homeobox 2 (CDX2), β-catenin, Carcinoembryonic antigen (CEA), Cytokeratin 7, and Cytokeratin 20, respectively. CDX2 and SATB2 were the most expressed markers. The expression rate had a significant association with tumor type. NSE and synaptophysin were the highest in neuroendocrine tumors, whereas CEA was more elevated in gablet cell carcinoids. Cytokeratin 20 is suitable for identifying epithelial cell neoplasms. Conclusion: The study indicates the proportion of positive cases in patients with primary neuroendocrine and epithelial cell appendiceal neoplasms.

Risk of lymph node metastases and conditional survival in appendiceal neuroendocrine neoplasms

BACKGROUND

National Comprehensive Cancer Network guidelines recommend segmental colectomy for appendiceal neuroendocrine neoplasms >2.0 cm given the risk for lymph node involvement. However, additional clinicopathologic factors are associated with nodal metastases, and thus survival. Given dynamic changes of prognosis over time, conditional overall survival, the probability of surviving after a specific interval, has emerged as a novel oncologic outcome, but is scarcely available for appendiceal neuroendocrine neoplasms.

METHODS

Adults with stage I-III appendiceal neuroendocrine neoplasms who underwent colectomy from 2010-2017 were identified in the National Cancer Database. Tumor histologies included neuroendocrine tumor grade 1, neuroendocrine tumor grades 2 and 3, neuroendocrine carcinoma, mixed neuroendocrine non-neuroendocrine neoplasm, and goblet cell carcinoma.

RESULTS

Of 3,541 patients (median age 51 years, 43% male, 88% White), 16% had positive lymph nodes. Overall, 40% had neuroendocrine tumor grade 1, 4% neuroendocrine tumor grades 2 and 3, 10% neuroendocrine carcinoma, 12% mixed neuroendocrine non-neuroendocrine neoplasm, and 30% goblet cell carcinoma. Increasing depth of invasion, lymphovascular invasion, and increasing size were associated with lymph node metastases. Eighty-seven percent were alive at 2 years. Mortality after 2 years was associated with older age, mixed neuroendocrine non-neuroendocrine neoplasm and goblet cell carcinoma histology, penetration through serosa, nodal involvement, and tumor size.

CONCLUSIONS

In a national cohort, 1 in 6 patients had positive lymph nodes, which was associated with depth of invasion, lymphovascular invasion, and size. These findings indicate additional factors should be considered when determining the extent of surgical resection and surveillance to improve survival outcomes. Additionally, patients with penetration through serosa, and mixed neuroendocrine non-neuroendocrine neoplasm or goblet cell carcinoma histology had worse conditional overall survival, potentially reflecting more aggressive tumor biology that warrants closer follow-up.

Long-term experience with octreotide and lanreotide for the treatment of gastroenteropancreatic neuroendocrine tumors

INTRODUCTION

The somatostatin analogs (SSA) octreotide and lanreotide are a mainstay in the treatment of neuroendocrine tumors (NET). The two pivotal trials differed considerably in terms of patient characteristics and are not directly comparable. Further comparative data are lacking.

METHODS

This retrospective chart review study included patients with gastroenteropancreatic NET grade 1 or 2 who were treated with octreotide LAR or lanreotide autogel. The main aim was to compare the two SSA based on progression-free survival (PFS) and overall survival (OS) from treatment start.

RESULTS

In total, 129 patients were analyzed, 60% (n = 77) had a small intestinal NET and 31% (n = 40) a pancreatic NET. Histologically, 34% (n = 44) had NET G1, 55% (n = 71) a NET G2, and 11% (n = 14) a NET G1/G2 unclassified. Lanreotide was used in 90 patients (70%) and octreotide in 39 patients (30%). Overall, the median PFS was 32.2 months (95% CI 23.0-42.9 months). No PFS difference (p = 0.8) was observed between lanreotide (29.8 months, 95% CI 18.7-48.5 months) and octreotide (36.0 months, 95% CI 23.2-68.2 months). Median OS from treatment start was calculated at 93.5 months (95% CI 71.1-132.9 months). Again, the median OS following lanreotide (113.4 months, 95% CI 62.3-NA months) or after octreotide (90.3 months, 95% CI 71.1-NA months) did not differ significantly (p > 0.9).

CONCLUSIONS

Our long-term experience with octreotide and lanreotide in NET did not reveal differences in antitumor effectiveness. This is consistent with previous reports and might suggest that both SSA can be used interchangeably if needed.

Gender impact on pancreatic neuroendocrine neoplasm (PanNEN) prognosis according to survival nomograms

PURPOSE

Personalizing care and outcome evaluation are important aims in the field of NEN and nomograms may represent useful tools for clinicians. Of note, gender difference is being progressively more considered in NEN care, as it may also impact on survival. This systematic review aims to describe and analyze the available nomograms on pancreatic NENs (PanNENs) to identify if gender differences are evaluated and if they could impact on patients' management and prognosis.

METHODS

We performed an electronic-based search using PubMed updated until June 2024, summarizing the available evidence of gender impact on PanNEN survival outcomes as emerges from published nomograms.

RESULTS

34 articles were identified regarding prognostic nomograms in PanNEN fields. The most included variables were age, tumor grade, tumor stage, while only 5 papers (14.7%) included sex as one of the key model variables with a significant impact on patients' prognosis. These 5 studies analyzed a total of 18,920 PanNENs. 3 studies found a significant impact of sex on overall survival (OS), whereas the remaining 2 studies showed no significant impact of sex on OS.

CONCLUSIONS

Gender difference is being progressively more considered in PanNEN diagnosis, care and survival. Nomograms represent a potentially useful tool in patients' management and in outcomes prediction in the field of PanNENs. A key role of sex in the prognosis of PanNENs has been found in few models, while definitive conclusions couldn't be drawn. Future studies are needed to finally establish gender impact on PanNEN prognosis.

Leptomeningeal Seeding of Pituitary Adenoma in a Young Lady With Neglected Gigantism: An Extremely Rare Case Report

Pituitary neuroendocrine tumors can sometimes present with leptomeningeal seeding at their initial diagnosis, emphasizing the need for thorough evaluation in cases of leptomeningeal involvement. Additionally, it is crucial for general physicians to inquire about a patient's menstrual status, particularly in low socioeconomic conditions, as this information can provide valuable insights into the hypothalamic-pituitary axis function.

KMT2C mutation in sporadic cribriform morular thyroid carcinoma: A rare case report and review of literature

Cribriform morular thyroid carcinoma is a rare thyroid malignancy with uncertain histogenesis. It predominantly affects young women and is strongly associated with familial adenomatous polyposis. This paper reports a rare case of sporadic cribriform morular thyroid carcinoma in a female patient in her early 50s, with somatic genetic testing revealing a KMT2C mutation. She presented with a solitary lesion confined to the right thyroid lobe and had no family history of familial adenomatous polyposis. Colonoscopy and germline genetic testing revealed no abnormalities. This finding suggests a potential link between KMT2C mutations and sporadic cribriform morular thyroid carcinoma. The clinical and imaging manifestations of this malignancy lack specificity, and the final diagnosis depends on routine pathological examination and immunohistochemical analysis. This report indicates the need for the clinical investigation of family history and genetic testing, thus contributing to the clinical realization of standardized follow-up monitoring and management.

Bone and muscle mass characteristics in patients with gastroenteropancreatic neuroendocrine neoplasms

BACKGROUND

Neuroendocrine neoplasms (NEN) are rare tumors arising from neuroendocrine cells most commonly in the gastrointestinal-tract. In recent years, advancements in therapeutics have increased survival rates in patients with NEN leading to a greater clinical burden compared to the general population.

METHODS

The aim of this single-center case-control study was to investigate the incidence of low bone mass and changes in body composition in adult patients diagnosed with gastroenteropancreatic neuroendocrine tumors (GEPNET). Enrolled participants underwent measurements of bone mineral density (BMD) at the lumbar spine (LS), femoral neck (FN), and total hip (TH) and body composition analysis with calculation of total fat-mass (TFM) and relative skeletal mass index (RSMI), by dual X-ray absorptiometry.

RESULTS

Ninety GEPNET patients (28 with Pancreatic-NET, 20 with small-intestine-NET, 42 with gastric-NET), and 50 age and sex-matched controls were enrolled. The mean disease duration was 5±4.4 years, the majority of patients (54/90) was classified as stage-1, and were not receiving systemic-treatment (76/90). The incidence of osteoporosis/osteopenia was threefold higher in the patients' cohort, compared to controls (OR: 3.17 95% CI 1.16-7.8, p < 0.001). Among NEN patients, gastric-NET had the lowest bone mass, especially in LS. In addition, GEPNET patients demonstrated significantly lower TFM and RSMI, compared to controls (TFM: 31.6 ± 9.6 kg vs. 38.6 ± 6.4 kg, respectively, p = 0.03; RSMI: 6.4 ± 1.1 vs. 8.2 ± 0.6, respectively, p < 0.001). Within our patients' cohort, RSMI was significantly associated with LS-BMD (rho = 0.49, p < 0.001) and TH-BMD (rho = 0.58, p < 0.001), and TFM was associated with TH-BMD (rho = 0.31, p = 0.004).

CONCLUSIONS

Patients with GEPNET even at an early stage exhibit significantly lower bone, muscle and fat mass compared to the non-NET population, highlighting the importance of continuous monitoring of the musculoskeletal system in these patients.

Nasolabial flap with mucous membrane for repairing extensive lower lip tissue defect: A case report

The structural integrity of the lips is essential for both aesthetic appeal and oral functionality. Defects in this region, which may arise from a variety of causes, can significantly affect a patient's physical and psychological well-being. This case report introduces a novel surgical technique designed for the repair of substantial defects in the lower lip. The procedure utilizes a nasolabial flap in conjunction with the facial artery myomucous flap. This innovative approach addresses considerable lip-related defect challenges effectively. The report delineates the surgical steps implemented and highlights the successful reconstruction of the lower lip. Following the surgery, the patient demonstrated a positive recovery trajectory, marked by significant improvements in both lip symmetry and functionality, with no notable complications. The integration of the nasolabial flap with the mucous membrane has proven effective in the repair of extensive lip defects, particularly in the skin and mucous membrane areas adjacent to the corners of the mouth. This procedure not only facilitates the restoration of appearance and function but also reduces the risk of further surgical trauma. Additionally, the report underscores the necessity of thorough preoperative planning to mitigate complications at the donor site.

Primary hepatic neuroendocrine neoplasms of children, a systematic review

The term "carcinoid tumour" is no longer used and has given up its place to neuroendocrine neoplasms (NENs). Primary hepatic neuroendocrine neoplasms (PHNENs) are as rare as compromising 0.4% of all neuroendocrine neoplasms (NENs). Searching the central medical databases of PubMed/Medline, Web of Science, Scopus, Google Scholar, and the references of the articles, we have collected 10 cases of pediatric PHNENs of children. The inclusion criteria were full-text available literature in English and those under and equal to 19 years old. Diseases found during autopsy, carcinoma, and isolated gall bladder involvement also made the exclusion criteria. The mean age of the patients was 13.86 years, ranging from 8 to 19 years. Six female patients (55%) were in front of 5 males (45%). The right lobe was the most frequent site of involvement and surgery in four cases. Abdominal pain comprised the main symptom, and CT scans of most of them were common which helped in diagnosis. While a hepatic tumour is considered NEN, a detailed systemic evaluation of a primary tumour is mandatory to exclude metastatic HNEN. Secondary hepatic NENs are more common than primary ones. Surgical resection has had the most long-term success.

Prevalence of Second Primary Malignancies in Patients With Well-Differentiated Neuroendocrine Tumors

OBJECTIVE

Neuroendocrine tumors (NETs) constitute a diverse group of tumors. NETs are often diagnosed late, due to nonspecific symptoms. Second Primary Malignancies (SPMs) have been reported in up to 25% of NETs and their incidence has been described as negative predictor of overall survival. We aimed to assess the prevalence of SPMs in patients with NETs treated at a specialized center.

METHODS

We conducted a retrospective analysis of patients with metastatic well-differentiated gastro-entero-pancreatic neuroendocrine tumors and lung carcinoids treated with Somatostatin Analogs between 2017 and 2019. Control group patients with hormonally inactive pituitary lesions and microprolactinomas hospitalized between 2016 and 2019 were included.

RESULTS

One hundred thirty-five patients (85 women, 50 men) with NETs were enrolled. SPMs were more common in NETs compared to control group (P = .029). Twenty-six SPMs were diagnosed in 24 patients (17.8%). The control group comprised 94 patients, among whom 7 patients (7.7%) developed SPMs. Mean (standard deviation) age at the end of follow-up was 64.8 (10.2) years, with duration from NETs diagnosis to the end of follow-up of 5.3 (3.8) years.

CONCLUSION

The risk of SPMs is high in NETs, with multiple neoplasms diagnosed in over one sixth of patients. Active surveillance for SPMs is strongly indicated and should be integral to the follow-up of NETs.

Incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs): An updated systematic review of population-based reports from 2010 to 2023

There is a general perception that the incidence of neuroendocrine neoplasms (NENs) has been increasing. Nevertheless, reports of actual population-based studies are scarce, and pertinent data from some geographical regions still need to be available. In this systematic literature review of population-based studies, we aimed to evaluate the available data to provide updated figures on the incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). Guided by the PRISMA 2020 statement reporting items for systematic reviews, this study conducted a systematic search using Ovid in the bibliographic databases Embase, Medline, and Web of Science Core Collection. Only incidence-reporting studies were included. In total, 847 articles were identified, and through a strict evaluation process using predefined inclusion and exclusion criteria, we found 19 papers that reported the general incidence of GEP-NENs from all sites. In addition, we considered another 15 papers that focused on the epidemiologic aspects of single-organ studies. While the incidence rates of GEP-NEN vary across similar countries, the general incidence of GEP-NEN has been increasing worldwide in recent decades. The incidence of GEP-NENs has increased worldwide over the last two decades, and reliable figures from new regions add to this pattern. Nevertheless, variations in the classification, grading, and reporting of GEP-NENs in various studies make direct comparisons difficult.

Neuroendocrine carcinoma causing common bile duct obstruction: a case report

A 46-year-old male with no comorbidities was referred to our hospital because of jaundice and elevated LFT markers. After further investigations, he underwent magnetic resonance cholangiopancreatography (MRCP), which revealed a hypo-enhancing periampullary mass measuring 15 mm in size causing common bile duct (CBD) dilatation of 12 mm in cross diameter with intrahepatic biliary obstruction, which explained the patient's symptoms. Side-view endoscopy was performed to obtain a specimen of the mass. Further histopathological workup revealed poorly differentiated neuroendocrine carcinoma (NEC). A multidisciplinary team (MDT) was conducted, and the patient was planned to undergo positron emission tomography-computed tomography (PET-CT) scan to investigate any further organ metastasis. Unfortunately, the patient missed his upcoming appointments and was lost to follow-up. Nevertheless, more research is needed to understand pathogenesis and the best course of management for small periampullary NETs.

The radiologic spectrum of neuroendocrine tumors in emergent care

Neuroendocrine tumors (NETs) are a diverse group of neoplasms whose prevalence is increasing globally, primarily due to advancements in diagnostic techniques. NETs arise from cells of the diffuse endocrine system and can occur in various locations, with the gastrointestinal tract being the most common. Their diverse clinical presentations, which range from asymptomatic to severe hormone-induced syndromes, pose significant diagnostic challenges. In emergency care, prompt recognition and management of complications such as bowel obstruction, ischemic events, hormonal crises, and metastases are critical. This review discusses the radiologic spectrum of NETs in emergent care, emphasizing the role of imaging in timely diagnosis and intervention.

Towards a better registration of neuroendocrine neoplasms: The results of the Italian retrospective population-based study

BACKGROUND

The increasing incidence, rapidly evolving classification, rarity and heterogeneity of neuroendocrine neoplasms (NENs) pose challenges to NEN registration including difficulty in distinguishing neuroendocrine carcinoma (NEC) and neuroendocrine tumours (NETs). Thus, in Italy a higher NEC incidence was reported. Focusing on gastroenteropancreatic (GEP) NEN, we aimed to review GEP NEN, and in particular cases of neuroendocrine carcinoma, not otherwise specified (NOS) and estimate the incidence of NEN, NET and NEC of the GEP.MethodsWe launched a pilot study examining cases of neuroendocrine carcinomas NOS (ICD-O3 code 8246) of GEP incidents in the years 2012-2020. Cancer registries (CRs) reviewed information included in the pathology report regarding differentiation and tumour cells proliferation to decide whether to confirm the case as neuroendocrine carcinoma NOS or register it as NET or NEC. After the review, we estimated the GEP NEN, NET and NEC incidence.

RESULTS

Nine CRs contributed to the pilot study. After review, in all CRs, only 31% of GEP NOS neuroendocrine carcinomas were confirmed; 50% were recoded as NETs, and approximately 17% of cases were non-NENs. The IR of GEP NENs was 2.99/100,000, and the incidence of NETs was higher than that of NECs.

CONCLUSION

After the review, the incidence of GEP NEN, NET and NEC in the eight Italian CRs involved was comparable to that reported in other European countries.

IMPACT

Our results confirmed that heterogeneity of cancer registries in the registration of NEN requires collaborative work to define and promote a standard definition to be extended to all Italian registries.

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.

Mixed neuroendocrine-non-neuroendocrine neoplasm of the colon treated with laparoscopic resection and adjuvant chemotherapy: a case report

Mixed neuroendocrine-non-neuroendocrine neoplasm (MiNEN) of the colon is rare with a poor prognosis. Since the first description of a mixed neoplasm 100 years ago, the nomenclature has evolved, most recently with the 2022 World Health Organization (WHO) classification system. We describe our experience of a case of locoregionally advanced MiNEN of the descending colon treated with curative laparoscopic resection and adjuvant chemotherapy. The patient is a 72 year old woman who presented with haematochezia. Initial clinical diagnosis was poorly differentiated adenocarcinoma of the descending colon, cT2N0M0, cStage I. Laparoscopic partial colectomy of the descending colon with D3 lymph node dissection and intracorporeal overlap anastomosis was performed. The pathological diagnosis however, returned mixed adenocarcinoma-neuroendocrine carcinoma (MANEC) of the descending colon, pT4aN1bM0, pStage IIIB, a subgroup of MiNEN: 70% was neuroendocrine carcinoma (NEC), whilst poorly differentiated mucinous carcinoma constituted 30% of the tumour. She completed 4 courses of irinotecan plus cisplatin (IP) adjuvant chemotherapy and is currently recurrence-free at postoperative year 2. The clinical course of MiNEN depends on the biology of the two components, both of which must be pathologically characterised. Even quantitatively discrete components should be carefully subtyped as their prognostic relevance is undetermined.

Nonfunctioning paraganglioma of the bladder mimicking nested variant of urothelial cancer: A case report and clinical management

INTRODUCTION AND IMPORTANCE

Non-functioning paraganglioma of the bladder is extremely rare disease. It is important to know the presence of paraganglioma of the bladder as the early and correct diagnosis affects the management and prognosis of the patient. Pathologists may misinterpret it as part of cystitis cystica/glandularis or nested variant urothelial carcinoma, or secondary bladder involvement by prostatic adenocarcinoma. This report will contribute to the existing literature and provide valuable insights into the clinical characteristics and treatment options for this rare tumor.

PRESENTATION OF CASE

35 years old female patient presented after incidental finding of bladder mass on abdominal ultrasound during routine antenatal follow up. Cystoscope showed 2 × 2 cm single solid bladder mass. Microscopic examination was suggestive of neuroendocrine tumor with paragangliom as a differential diagnosis. Imminohistochemical studies showed positive for synaptophysin, S100, GATA-3 and negative for panCK. The patient was managed with partial cystectomy.

CLINICAL DISCUSSION

Non-functioning paragnaglioma of the urinary bladder is a rare extra-adrenal pheochromocystoma. The diagnosis is usually challenging and it may mimic urothelial carcinoma. Histopathology and immunohistochemistry are almost always confirmatory.

CONCLUSION

Urinary bladder paraganglioma may mimic nested variant of the bladder tumor. High clinical suspicion is important. Confirmation is with histopathology and immunohistochemistry. Partial cystectomy is treatment of choice.

Pituitary adenomas: biology, nomenclature and clinical classification

An 'adenoma' is a benign neoplasm composed of epithelial tissue, and has been standard nomenclature for primary pituitary neoplasms. In 2022, the fifth edition of the WHO Classification of Endocrine Tumours and of Central Nervous System Tumours, renamed pituitary adenomas as neuroendocrine tumours (NETs), assigning an oncology label to pituitary invariably benign neoplasms. Multidisciplinary workshops convened by the Pituitary Society have questioned the process, validity, and merit of this arbitrary change, while addressing the adverse clinical implications of the proposed new nomenclature. Unlike NETs, pituitary adenomas are highly prevalent, indolent and very rarely become malignant, and in general do not affect life expectancy when appropriately managed. A nomenclature change to NET does not advance mechanistic insight, treatment or prognosis but confers a misleading oncology connotation, potentially leading to overtreatment as well as engendering unnecessary patient anxiety. As the majority of pituitary adenomas do not require surgery, exclusion of these disorders is a major shortcoming of the pathology-based WHO classification system which is limited to patients undergoing surgery. Many factors influence prognosis other than histopathology. A new clinical classical classification has been developed for guiding prognosis and therapy of pituitary adenomas by integrating clinical, genetic, biochemical, radiological, pathological, and molecular information for all adenomas arising from anterior pituitary cell lineages. The system uses an evidence-based scoring of risk factors to yield a cumulative grade score that reflects disease severity. It can be used at the bedside to guide pituitary adenoma management. Once validated in prospective studies, this simple classification system could provide a standardised platform for assessing disease severity, prognosis, and effects of therapy on pituitary adenoma outcomes.

Utility of the manual hematology cell counter for Ki-67 assessment in gastrointestinal and pancreatobiliary well-differentiated neuroendocrine tumors

In the World Health Organization (WHO) 5th edition, prognosis of gastrointestinal (GI) well-differentiated neuroendocrine tumors (WDNET) depends on proliferation rate, commonly assessed by ki-67 immunohistochemical stain. In daily practice, the gold standard for WHO grade assessment by ki-67 staining, printing a photo of a tumor hotspot, counting the number of ki-67-positive cells out of 500 tumor cells, and calculating a percentage, is time-consuming and many cases are eyeballed. This study investigates the utility of a common tool, the manual cell counter used in hematology smear cell counting, for GI WDNET ki-67 counting. Of 59 resections, the number of cases with a WHO grade difference between gold standard print-and-count and the original report, eyeballing, and hematology counter method, was 23 (39 %), 14 (24 %) and 7 (12 %) cases, respectively. Of 37 biopsies, the number of cases with a WHO grade difference between gold standard print-and-count and the original report, eyeballing, and hematology counter method, was 10 (27 %), 12 (32 %) and 7 (19 %) cases, respectively. For resections, Chi square analysis comparing hematology counter method versus original report, where many cases were likely eyeballed, showed statistically significantly less cases with differing WHO grades from gold standard print-and-count for hematology counter-assessed cases (P = 0.0007), and the same Chi square analysis was marginally not significant (P = 0.09) for hematology counter versus eyeballing. Times taken to perform hematology counter method were statistically significantly lower than times taken for print-and-count. This study suggests the hematology cell counter could strike a reasonable balance between time and accuracy for WDNET resections.

The Usefulness of the International Grading System in the Management of Sporadic Medullary Thyroid Carcinoma

Background: The international medullary thyroid carcinoma (MTC) grading system (IMTCGS) has been proposed as an independent tool to predict disease-specific survival (DSS), distant metastasis-free survival (DMFS), and locoregional recurrence-free survival (LRFS). We aimed to evaluate the performance of IMTCGS in our series of sporadic MTCs and to compare its predictive power with conventional prognostic factors. Methods: In a retrospective cohort study, we evaluated data from 314 patients with sporadic MTC, all managed at the Pisa University Hospital. We divided patients according to the extent of the disease at diagnosis into localized (183/314, 58.3%) (confined to the thyroid), regional (100/314, 31.8%) (limited to the neck, involving surrounding thyroid tissues and/or regional lymph nodes), and distant (31/314, 9.9%) (distant metastases) disease. Data about somatic mutations were available in 212/314 (67.5%) patients. Expert pathologists differentiated high- and low-grade tumors. Results: According to the IMTCGS, 115/314 (36.6%) had high- and 199/314 (63.4%) patients had low-grade tumors. Patients with high-grade tumors showed higher preoperative calcitonin levels compared with low-grade (542 vs. 76 pg/mL, p < 0.01) as well as larger tumor size (2.3 vs. 1.1 cm, p < 0.01) and more frequent multifocality (22.6 vs. 12.1%, p = 0.01), minimal extrathyroidal extension (30.4 vs. 9.5%, p < 0.01), and lymph node metastases (63.5 vs. 27.6%, p < 0.01). Overall, patients with high-grade showed lower DSS, LRFS, and DMFS (p < 0.01). Grouping the whole cohort according to different disease extent at diagnosis, only in the case of localized disease, patients with high-grade tumors had significantly lower LRFS compared with low-grade. Similarly, in the other subgroups, we did not identify any difference in DSS, LRFS, and DMFS. Moreover, in the case of RET aggressive mutations, no differences in DSS, LRFS, and DMFS were observed between high- and low-grade tumors. Conclusions: We confirmed the usefulness of IMTCGS in predicting DSS, LRFS, and DMFS. However, it finds the best utility in patients with a lower risk of recurrence and mortality, identifying those rare cases with more aggressive clinical behavior. Conversely, when laterocervical lymph nodes (N1), distant metastasis (M1), or RET mutations, particularly M918T or indels, are already present at diagnosis, the role of IMTCGS in predicting DSS, DMFS, and LRFS becomes less relevant.

Small Cell Lung Cancer: A Review

Importance

Small cell lung cancer (SCLC) is a high-grade neuroendocrine carcinoma with an incidence of 4.7 cases per 100 000 individuals in 2021 in the US and a 5-year overall survival of 12% to 30%.

Observations

Cigarette smoking is the primary risk factor for development of SCLC, as 95% of patients diagnosed with SCLC have a history of tobacco use. Patients with SCLC may present with respiratory symptoms such as cough (40%), shortness of breath (34%), hemoptysis (10%), or metastases with corresponding local symptoms (30%) such as pleuritis or bone pain; approximately 60% of patients with SCLC may be asymptomatic at diagnosis. Chest imaging may demonstrate central hilar (85%) or mediastinal lymphadenopathy (75%). At diagnosis, approximately 15% of patients have brain metastases, which may present as headache or focal weakness. Diagnosis is confirmed by biopsy of a primary lung mass, thoracic lymph node, or metastatic lesion. Small cell lung cancer is classified into limited stage (LS-SCLC; 30%) vs extensive stage (ES-SCLC; 70%) based on whether the disease can be treated within a radiation field that is typically confined to 1 hemithorax but may include contralateral mediastinal and supraclavicular nodes. For patients with LS-SCLC, surgery or concurrent chemotherapy with platinum-etoposide and radiotherapy is potentially curative in 30% of patients. More recently, median survival for LS-SCLC has reached up to 55.9 months with the addition of durvalumab, an immunotherapy. First-line treatment for ES-SCLC is combined treatment with platinum-etoposide chemotherapy and immunotherapy with the programmed cell death 1 ligand 1 (PD-L1) inhibitors durvalumab or atezolizumab followed by maintenance immunotherapy until disease progression or toxicity. Although initial rates of tumor shrinkage are 60% to 70% with platinum-etoposide and immunotherapy treatment, the median overall survival of patients treated for ES-SCLC is approximately 12 to 13 months, with 60% of patients relapsing within 3 months. Second-line therapy for patients with ES-SCLC includes the DNA-alkylating agent lurbinectedin (35% overall response rate; median progression-free survival, 3.7 months) and a bispecific T-cell engager against delta-like ligand 3, tarlatamab (40% overall response rate; median progression-free survival, 4.9 months).

Conclusions and Relevance

Small cell lung cancer is a smoking-related malignancy that presents at an advanced stage in 70% of patients. Three-year overall survival is approximately 56.5% for LS-SCLC and 17.6% for ES-SCLC. First-line treatment for LS-SCLC is radiation targeting the tumor given concurrently with chemotherapy and followed by consolidation immunotherapy. For ES-SCLC, first-line treatment is chemotherapy and immunotherapy followed by maintenance immunotherapy.

Molecular Classification and Characterization of Noninsulinoma: Ready for Prime Time in Clinical Practice?

Pancreatic neuroendocrine tumors are a heterogeneous group of rare clinical tumors, which can be classified into functional pancreatic neuroendocrine tumor (insulinoma is the most common) and noninsulinoma. Insulinoma and noninsulinoma have different mutation profiles. In noninsulinoma, ATRX/DAXX mutation is associated with alternative lengthening of telomeres-positive phenotype and positively correlated with poor prognosis. Copy number variation is also a prognostic marker for a high risk of recurrence. Scholars have used epigenetics as well as a multiomics approach (combining epigenetics, metabolomics, proteomics, etc) to molecularly type noninsulinoma, and there are huge differences in molecular expression and patient prognosis between different groups. In this manuscript, we summarize the published studies that utilized genome, epigenome, transcriptome, and proteome data to classify noninsulinoma.

Oncocytic subtype of well differentiated neuroendocrine tumor: clinicopathologic and molecular associations of a cohort diagnosed on fine needle aspiration (FNA)

INTRODUCTION

Classical well differentiated neuroendocrine tumors (C-NETs) have plasmacytoid morphology and neuroendocrine differentiation. Oncocytic NETs (O-NETs) have been shown to be more clinically aggressive. Whether O-NETs are more akin to C-NETs or poorly differentiated neuroendocrine carcinomas (PDNECs) is not established.

MATERIALS AND METHODS

Clinicopathologic characteristics and immunohistochemical expression of death domain-associated protein (DAXX), α-thalassemia/mental retardation syndrome X-linked genes (ATRX), retinoblastoma 1, p53, and SMAD4 in 30 O-NETs (25 pancreatic and 4 from luminal gastrointestinal tract) was compared to 32 C-NETs (23 pancreatic and 8 from luminal gastrointestinal tract). Whole exome sequencing was performed in a subset of each cohort.

RESULTS

O-NETs were male-predominant (65.6%) and had higher mean Ki-67 index (7.4% versus 2.9% in C-NETs) (P = 0.03), corresponding to more grade 2 or above (53.3%) tumors. O-NET patients had more advanced disease (pT3/pT4, 75% versus 36.8%) (P = 0.024), distant metastasis (50% versus 25%) (P = 0.042), progression (increased size/recurrence/new metastases) (n = 8 versus 3; P = 0.1), and death (n = 3 versus 1; P = 0.32). Forty percent of O-NETs (versus 12.5% of C-NETs; P = 0.041) showed DAXX/ATRX loss, with one showing coexisting retinoblastoma 1 and SMAD4 loss. P53 staining pattern was wild type in all cases. Whole exome sequencing of 10 cases showed DAXX, ATRX, and multiple endocrine neoplasia type 1 alterations in O-NETs and C-NETs, and coexisting DNMT3A and MTOR alterations in one O-NET.

CONCLUSIONS

O-NET subtype is associated with advanced disease and unfavorable outcomes compared to C-NETs. O-NETs are cytologically distinct, male-predominant tumors that often present with higher grade and advanced disease. Their aggressive behavior is possibly related to frequent DAXX/ATRX loss and less likely PDNEC-related molecular alterations. Pathologists should be mindful of this aggressive morphologic subtype and clearly convey its presence in pathology reports.

Identification of metabolite biomarkers for pancreatic neuroendocrine tumours using a metabolomic approach

IMPORTANCE

Metabolic flexibility, a key hallmark of cancer, reflects aberrant tumour changes associated with metabolites. The metabolic plasticity of pancreatic neuroendocrine tumours (pNETs) remains largely unexplored. Notably, the heterogeneity of pNETs complicates their diagnosis, prognosis, and therapeutic management.

OBJECTIVE

Here, we compared the plasma metabolomic profiles of patients with pNET and non-cancerous individuals to understand metabolic dysregulation.

DESIGN, SETTING, PARTICIPANTS, INTERVENTION AND MEASURE

Plasma metabolic profiles of 76 patients with pNETs and 38 non-cancerous individuals were analyzed using LC-MS/MS and FIA-MS/MS (Biocrates AbsoluteIDQ p180 kit). Statistical analyses, including univariate and multivariate methods, were performed along with the generation of receiver operating characteristic (ROC) curves for metabolomic signature identification.

RESULTS

Compared with non-cancerous individuals, patients with pNET exhibited elevated levels of phosphoglyceride metabolites and reduced acylcarnitine levels, indicating an upregulation of fatty acid oxidation (FAO), which is crucial for the energy metabolism of pNET cells and one-carbon metabolism metabolites. Elevated glutamate levels and decreased lipid metabolite levels have been observed in patients with metastatic pNETs. Patients with the germline MEN1 mutations showed lower amino acid metabolites and FAO, with increased metabolites related to leucine catabolism and lipid metabolism, compared to non-MEN1 mutated patients. The highest area under the ROC curve was observed in patients with pNET harbouring MEN1 mutations.

CONCLUSION AND RELEVANCE

This study highlights the distinct plasma metabolic signatures of pNETs, including the critical role of FAO and elevated glutamate levels in metastasis, supporting the energy and biosynthetic needs of rapidly proliferating tumour cells. Mapping of these dysregulated metabolites may facilitate the identification of new therapeutic targets for pNETs management.