The Levels of Tumor Markers in Pancreatic Neuroendocrine Carcinoma and Their Values in Differentiation Between Pancreatic Neuroendocrine Carcinoma and Pancreatic Ductal Adenocarcinoma

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.

Predictors Based on the Radiologic Characteristics for Aggressiveness of Small (< 20 mm) Nonfunctioning Pancreatic Neuroendocrine Tumors

BACKGROUND AND OBJECTIVES

To find the association between preoperative computed tomography (CT) features combined with tumor marker and known high-risk factors of small nonfunctioning pancreatic neuroendocrine tumors (NF-PNETS), thereby selecting appropriate treatment strategy for these patients.

METHOD

One hundred fourteen patients with NF-PNETs< 20 mm who underwent surgical operation were retrospectively analyzed from 2009 to 2023. Univariate and multivariable logistic regression analyses were performed to find the relationship between preoperative clinical psychological and CT features and high-risk factors. The overall survival (OS) rates with and without high-risk factors were compared.

RESULTS

Of 114 patients, 29(25%) had at least one of these high-risk factors. Main pancreatic duct dilation (OR, 3.315; 95% CI, 1.079-10.184; p = 0.036), irregular tumor margin (OR, 2.955; 95% CI, 1.021-8.551; p = 0.046), positive tumor marker (OR, 6.047; 95% CI, 1.408-25.963; p = 0.015) were associated with increased odds of having any of these high-risk factors. The time to death differed significantly between patients with and without high-risk factors. Patients combining with high-risk factors were associated with lower 3- and 5-year OS (100% vs. 81.8%, 93.1% vs. 81.8%, respectively; p = 0.035 for both).

CONCLUSION

Main pancreatic duct dilation, irregular tumor margin and positive tumor marker could screen a subset of patients recommended for surgery.

Clinical and CT Quantitative Features for Predicting Liver Metastases in Patients with Pancreatic Neuroendocrine Tumors: A Study with Prospective/External Validation

RATIONALE AND OBJECTIVES

We aimed to evaluate clinical characteristics and quantitative CT imaging features for the prediction of liver metastases (LMs) in patients with pancreatic neuroendocrine tumors (PNETs).

METHODS

Patients diagnosed with pathologically confirmed PNETs were included, 133 patients were in the training group, 22 patients in the prospective internal validation group, and 28 patients in the external validation group. Clinical information and quantitative features were collected. The independent variables for predicting LMs were confirmed through the implementation of univariate and multivariate logistic analyses. The diagnostic performance was evaluated by conducting receiver operating characteristic curves for predicting LMs in the training and validation groups.

RESULTS

PNETs with LMs demonstrated significantly larger diameter and lower arterial/portal tumor-parenchymal enhancement ratio, arterial/portal absolute enhancement value (AAE/PAE value) (p < 0.05). After multivariate analyses, A high level of tumor marker (odds ratio (OR): 5.32; 95% CI, 1.54-18.35), maximum diameter larger than 24.6 mm (OR: 7.46; 95% CI, 1.70-32.72), and AAE value ≤ 51 HU (OR: 4.99; 95% CI, 0.93-26.95) were independent positive predictors of LMs in patients with PNETs, with area under curve (AUC) of 0.852 (95%CI, 0.781-0.907). The AUCs for prospective internal and external validation groups were 0.883 (95% CI, 0.686-0.977) and 0.789 (95% CI, 0.602-0.916), respectively.

CONCLUSION

Tumor marker, maximum diameter and absolute enhancement value in arterial phase were independent predictors with good predictive performance for the prediction of LMs in patients with PNETs. Combining clinical and quantitative features may facilitate the attainment of good predictive precision in predicting LMs.

Recent developments in the diagnosis of pancreatic neuroendocrine neoplasms

INTRODUCTION

Pancreatic Neuroendocrine Neoplasms (PanNENs) are characterized by a highly heterogeneous clinical and biological behavior, making their diagnosis challenging. PanNENs diagnostic work-up mainly relies on biochemical markers, pathological examination, and imaging evaluation. The latter includes radiological imaging (i.e. computed tomography [CT] and magnetic resonance imaging [MRI]), functional imaging (i.e. 68Gallium [68 Ga]Ga-DOTA-peptide PET/CT and Fluorine-18 fluorodeoxyglucose [18F]FDG PET/CT), and endoscopic ultrasound (EUS) with its associated procedures.

AREAS COVERED

This review provides a comprehensive assessment of the recent advancements in the PanNENs diagnostic field. PubMed and Embase databases were used for the research, performed from inception to October 2023.

EXPERT OPINION

A deeper understanding of PanNENs biology, recent technological improvements in imaging modalities, as well as progresses achieved in molecular and cytological assays, are fundamental players for the achievement of early diagnosis and enhanced preoperative characterization of PanNENs. A multimodal diagnostic approach is required for a thorough disease assessment.

Near complete remission of an inoperable pancreatic acinar cell carcinoma after BRAF-/MEK-inhibitor treatment-A case report and review of the literature

INTRODUCTION

Pancreatic acinar cell carcinomas are rare malignant neoplasms. High-quality evidence about the best treatment strategy is lacking. We present the case of a 52-year-old male with a BRAFV600E -mutated PACC who experienced a complete remission after chemotherapy with BRAF-/MEK-inhibitors.

CASE

The patient presented with upper abdomen pain, night sweat, and weight loss. CT scan showed a pancreatic tumor extending from the pancreas head to body. Histological workup identified an acinar cell carcinoma. As the tumor was inoperable, chemotherapy with FOFIRNIOX was initiated and initially showed a slight regression of disease. The regimen had to be discontinued due to severe side effects. Molecular analysis identified a BRAFV600E mutation, so the patient was started on BRAF- and MEK-inhibitors (dabrafenib/trametinib). After 16 months, CT scans showed a near complete remission with a markedly improved overall health.

DISCUSSION

Studies suggest that up to one-fourth of PACCs carry a BRAF mutation and might therefore be susceptible to a BRAF-/MEK-inhibitor therapy. This offers a new therapeutic pathway to treat this rare but malignant neoplasm.

Dual-energy CT improves differentiation of non-hypervascular pancreatic neuroendocrine neoplasms from CA 19-9-negative pancreatic ductal adenocarcinomas

PURPOSE

To evaluate the utility of dual-energy CT (DECT) in differentiating non-hypervascular pancreatic neuroendocrine neoplasms (PNENs) from pancreatic ductal adenocarcinomas (PDACs) with negative carbohydrate antigen 19-9 (CA 19-9).

METHODS

This retrospective study included 26 and 39 patients with pathologically confirmed non-hypervascular PNENs and CA 19-9-negative PDACs, respectively, who underwent contrast-enhanced DECT before treatment between June 2019 and December 2021. The clinical, conventional CT qualitative, conventional CT quantitative, and DECT quantitative parameters of the two groups were compared using univariate analysis and selected by least absolute shrinkage and selection operator regression (LASSO) analysis. Multivariate logistic regression analyses were performed to build qualitative, conventional CT quantitative, DECT quantitative, and comprehensive models. The areas under the receiver operating characteristic curve (AUCs) of the models were compared using DeLong's test.

RESULTS

The AUCs of the DECT quantitative (based on normalized iodine concentrations [nICs] in the arterial and portal venous phases: 0.918; 95% confidence interval [CI] 0.852-0.985) and comprehensive (based on tumour location and nICs in the arterial and portal venous phases: 0.966; 95% CI 0.889-0.995) models were higher than those of the qualitative (based on tumour location: 0.782; 95% CI 0.665-0.899) and conventional CT quantitative (based on normalized conventional CT attenuation in the arterial phase: 0.665; 95% CI 0.533-0.797; all P < 0.05) models. The DECT quantitative and comprehensive models had comparable performances (P = 0.076).

CONCLUSIONS

Higher nICs in the arterial and portal venous phases were associated with higher blood supply improving the identification of non-hypervascular PNENs.

Diagnostic role and prognostic value of tumor markers in high-grade gastro-enteropancreatic neuroendocrine neoplasms

OBJECTIVES

High-grade gastro-enteropancreatic neuroendocrine neoplasms (GEP-NENs) are a heterogeneous group of rare tumors of two different types: well differentiated neuroendocrine tumors grade 3 (NETs G3) and poorly differentiated neuroendocrine carcinomas (NECs). This study aimed to explore the value of eight common preoperative markers in differentiating NETs G3 from NECs and the prognosis prediction of high-grade GEP-NENs.

METHODS

Seventy-two patients diagnosed with high-grade GEP-NENs who underwent surgery at our institution were recruited for this study. Demographic and clinicopathological characteristics, preoperative serum tumor markers, and survival data were collected and analyzed. Kaplan-Meier methods were used to analyze survival rates, and a Cox regression model was used to perform multivariate analyses.

RESULTS

Serum carcinoembryonic antigen (CEA) was dramatically higher in NECs than in NETs G3 (P = 0.025). After follow-up, 57 of the 72 patients remained for survival analysis. Elevated serum carbohydrate antigen 19-9 (CA19-9), CEA, cancer antigen 125 and sialic acid (SA) levels indicated poorer survival of high-grade GEP-NEN patients. Only CA19-9 (HR: 6.901, 95% CI: 1.843 to 25.837, P = 0.004) was regarded as an independent risk factor for overall survival. Serum CA19-9 (HR: 4.689, 95% CI: 1.127 to 19.506, P = 0.034) was also regarded as an independent factor for overall survival in NECs.

CONCLUSIONS

Serum CEA levels can be used to distinguish NETs G3 from NECs. Preoperative CA19-9, CEA, cancer antigen 125 and SA levels have predictive value in the prognosis of high-grade GEP-NENs. Preoperative CA19-9, neuron-specific enolase, and SA levels can predict the prognosis of NECs.

Radiomics Combined with Multiple Machine Learning Algorithms in Differentiating Pancreatic Ductal Adenocarcinoma from Pancreatic Neuroendocrine Tumor: More Hands Produce a Stronger Flame

The aim of this study was to assess the diagnostic ability of radiomics combined with multiple machine learning algorithms to differentiate pancreatic ductal adenocarcinoma (PDAC) from pancreatic neuroendocrine tumor (pNET). This retrospective study included a total of 238 patients diagnosed with PDAC or pNET. Using specialized software, radiologists manually mapped regions of interest (ROIs) from computed tomography images and automatically extracted radiomics features. A total of 45 discriminative models were built by five selection algorithms and nine classification algorithms. The performances of the discriminative models were assessed by sensitivity, specificity and the area under receiver operating characteristic curve (AUC) in the training and validation datasets. Using the combination of Gradient Boosting Decision Tree (GBDT) as the selection algorithm and Random Forest (RF) as the classification algorithm, the optimal diagnostic ability with the highest AUC was presented in the training and validation datasets. The sensitivity, specificity and AUC of the model were 0.804, 0.973 and 0.971 in the training dataset and 0.742, 0.934 and 0.930 in the validation dataset, respectively. The combination of radiomics and multiple machine learning algorithms showed the potential ability to discriminate PDAC from pNET. We suggest that multi-algorithm modeling should be considered for similar studies in the future rather than using a single algorithm empirically.

A Case of Pancreatic Neuroendocrine Tumor G3 Which Responded Remarkably to Chemotherapy

Pancreatic neuroendocrine carcinoma (NEC) as classified in the World Health Organization (WHO) 2010 was reclassified in the WHO 2017 as either neuroendocrine tumor (NET) G3 or NEC. An accurate diagnosis based on the WHO 2017 classification is important in order treating this disease appropriately. We report a case diagnosed as NET G3 that responded remarkably well to treatment with streptozocin. The patient would likely not have received the streptozocin treatment if she had been diagnosed with NEC. The WHO 2017 classification is reasonable for the treatment of advanced pancreatic neuroendocrine neoplasms.

Serum Biomarker Status with a Distinctive Pattern in Prognosis of Gastroenteropancreatic Neuroendocrine Carcinoma

OBJECTIVE

Gastroenteropancreatic neuroendocrine carcinoma (GEPNEC) is a major research focus, but the application of biomarkers to guide its prognostication and management is unsatisfying. Clinical values of conventional serum biomarkers, neuron-specific enolase (NSE), carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA199) warrant scrutiny.

METHODS

Patients diagnosed with GEPNEC with baseline NSE, CEA, and CA199 levels provided in Peking University Cancer Hospital were retrospectively studied. Relationships between biomarkers and prognosis were investigated by the χ2 test, Kaplan-Meier analysis, and univariate and multivariate Cox regression analyses.

RESULTS

A total of 640 GEPNEC patients were enrolled. NSE, CEA, and CA199 were elevated in 59.5%, 28.5%, and 21.3% of the population, respectively. Higher NSE had worse median overall survival (OS) (17.0 months vs. not reached, hazard ratio = 2.77 [2.06, 3.73], p < 0.001), and so did patients with higher CEA and CA199. Multivariable analysis confirmed that NSE and CA199 correlated with OS independently. Baseline NSE level and NSE remission predicted OS and the response of patients with first-line etoposide plus cisplatin (EP) treatment. Furthermore, we combined NSE/CEA/CA199 to segregate GEPNEC into novel subgroups, namely, adenocarcinoma-like NEC (ALN), neuroendocrine-like NEC (NLN), and triple-normal NEC (TNN). The groups shared distinctive clinicopathologic features and prognosis (21.0 months vs. 17.1 months vs. not reached, p < 0.001). The EP regimen remained the priority treatment option in NLN/TNN, while ALN was predisposed to "adenocarcinoma-like chemotherapy."

CONCLUSIONS

Elevation of NSE, CEA, or CA199 was common and independently indicates poor prognosis in GEPNEC patients. Serum biomarker-based subtypes suggest meaningful clinical implications and appropriate therapeutic approaches, illuminating promising ways to characterize the prognosis of GEPNEC.

Increased carbohydrate antigen 19-9 expression in a thymic neuroendocrine tumor

Here, we report a case of carbohydrate antigen (CA) 19‐9‐producing mediastinal neuroendocrine tumor (NET) (atypical carcinoid). A 54‐year‐old woman with no specific relevant medical history was referred to our hospital because of increased CA19‐9 (95.3 U/ml) detected on health screening. Chest computed tomography (CT) revealed an anterior mediastinal mass without localized lymphadenopathy. Thoracic surgery was performed and the histopathological diagnosis was thymic CA19‐9‐positive NET. The patient developed mediastinal lymph node metastasis at 1 year (CA19‐9: 413 U/ml) and multiple bone metastases 4 years (CA19‐9: 2303 U/ml) after surgery. Increased CA19‐9 levels paralleled the clinical courses of relapse. To our knowledge, this is the first report of CA19‐9‐producing thymic NET.

Molecular drivers and cells of origin in pancreatic ductal adenocarcinoma and pancreatic neuroendocrine carcinoma

Pancreatic cancer is one of the most common causes of cancer-related deaths worldwide. The two major histological subtypes of pancreatic cancer are pancreatic ductal adenocarcinoma (PDAC), accounting for 90% of all cases, and pancreatic neuroendocrine neoplasm (PanNEN), which makes up 3-5% of all cases. PanNEN is classified into well-differentiated pancreatic neuroendocrine tumor and poorly-differentiated pancreatic neuroendocrine carcinoma (PanNEC). Although PDAC and PanNEN are commonly thought to be different diseases with distinct biology, cell of origin, and genomic abnormalities, the idea that PDAC and PanNEC share common cells of origin has been gaining support. This is substantiated by evidence that the molecular profiling of PanNEC is genetically and phenotypically related to PDAC. In the current review, we summarize published studies pointing to common potential cells of origin and speculate about how the distinct paths of differentiation are determined by the genomic patterns of each disease. We also discuss the overlap between PDAC and PanNEC, which has been noted in clinical observations.

Tumour markers and their utility in imaging of abdominal and pelvic malignancies

The utility of tumour biomarkers has increased considerably in the era of personalised medicine and individualised therapy in oncology. Biomarkers may be prognostic or predictive, and only a handful of markers are currently US Food and Drug Administration (FDA)-approved for clinical use. Tumour markers have a wide array of uses such as screening, establishing a differential diagnosis, assessing risk, prognosis, and treatment response, as well as monitoring disease status. Major overlap exists between biomarkers and their associated pathologies; therefore, despite suggestive imaging features, establishing a differential diagnosis may be challenging for the radiologist. We review common biomarkers that are of interest to radiologists such as carcinoembryonic antigen (CEA), lactate dehydrogenase (LDH), prostate-specific antigen (PSA), beta human chorionic gonadotropin (β-hCG), carbohydrate antigen 19-9 (CA 19-9), alpha fetoprotein (AFP), and carbohydrate or cancer antigen 125 (CA 125), as well as their associated malignant and non-malignant pathologies. We also present relevant case examples from our practice.

Grade 3 Pancreatic Neuroendocrine Tumors on MDCT: Establishing a Diagnostic Model and Comparing Survival Against Pancreatic Ductal Adenocarcinoma

OBJECTIVE. The purpose of this study is to establish a diagnostic model for differentiating grade 3 (G3) pancreatic neuroendocrine tumors (PNETs) from pancreatic ductal adenocarcinomas (PDACs) and to analyze survival outcomes. MATERIALS AND METHODS. Twenty patients with G3 PNETs and 58 patients with PDACs confirmed by surgery or biopsy were retrospectively included. Demographic and radiologic information was collected. Univariate analyses and binary logistic regression analyses were performed to identify independent factors and establish a diagnostic model. An ROC curve was created to determine diagnostic ability. Kaplan-Meier survival analysis was performed. RESULTS. Patients with G3 PNETs were more likely to present with normal carbohydrate antigen (CA) 19-9 levels, normal pancreatic ducts, and round tumors with well-defined margins and higher portal enhancement ratios than were patients with PDAC (p < 0.05). After multivariate analysis, a normal CA 19-9 level (odds ratio, 0.0125; 95% CI, 0.0008-0.2036), round tumor shape (odds ratio, 0.0143; 95% CI, 0.0004-0.5461), and pancreatic duct dilation of 4 mm or less (odds ratio, 17.9804; 95% CI, 1.0098-320.1711) were independent predictors of G3 PNETs. The AUC of the ROC curve was 0.916, and sensitivity and specificity were 90.0% and 81.0%, respectively. Furthermore, patients with G3 PNETs had better overall survival than patients with PDACs. Among patients in the G3 PNET subgroup, patients with liver or lymph node metastases had worse overall survival than patients without metastases. CONCLUSION. A diagnostic model was established to differentiate G3 PNETs from PDACs. A normal CA 19-9 level, round tumor shape, and pancreatic duct dilation of 4 mm or less were factors that were strongly predictive of G3 PNET.

CA 19-9 levels in patients with acute pancreatitis due to gallstone and metabolic/toxic reasons

OBJECTIVE

Acute pancreatitis (AP) is an important clinical event with an increased frequency due to increased life expectancy, obesity, and alcohol use. There are some data about the elevation of carbohydrate antigen (CA) 19-9 levels in benign and malignant pancreaticobiliary events in the literature, but in AP they are limited. The aim of this study was to evaluate the CA 19-9 level in patients with AP and determine its relationship according to the cause.

METHODS

Between 2010-2018, 173 patients evaluated with CA 19-9 levels as well as by standard laboratory tests were included in the study. CA 1 9-9 levels and laboratory findings were compared in patients with pancreatitis due to gallstone (group 1) and metabolic/toxic reasons such as hyperlipidemia, alcohol, or drug use (group 2).

RESULTS

There were 114 (66%) patients in the group 1 and 59 (34%) patients in the group 2. The majority of patients with high CA 19-9 level were in group 1 (92.1% vs 6.8%). CA 19-9 level, as well as amylase, lipase, AST, ALT and bilirubin levels were found to be statistically higher in patients with AP due to gallstone compared to patients with metabolic/toxic AP.

CONCLUSIONS

Patients with AP due to gallstone, were found to have a high level of CA 19-9 at admission. Early stage CA 19-9 levels may contribute to standard laboratory tests in the etiology of the disease in patients diagnosed with AP.