Diagnostic value of chromogranin A in pancreatic neuroendocrine tumors depends on tumor size: A prospective observational study from a single institute

Chromogranin A (CgA) is the most widely accepted biomarker for neuroendocrine tumors (NET) but its diagnostic accuracy is dependent on tumor type and the use of proton-pump inhibitors (PPI). We investigated the diagnostic value of circulating miRNAs along with CgA in pancreatic neuroendocrine tumors (pNET). 74 serum samples from patients with pNET (n = 25, nonfunctioning), pheochromocytoma/paraganglioma (PPGL, n = 20), healthy individuals with normal CgA (n = 29) including 10 samples from 5 healthy individuals with and without current PPI treatment were collected. MiRNA expression profiles were determined using next-generation sequencing, followed by validation with individual TaqMan assays. A global downregulation of miRNAs was observed in patients with NET compared to controls. MiRNA expression of 33 miRNAs was able to discriminate tumor samples from controls. No miRNA alone could be considered as an applicable biomarker for pNET or PPGL. However, using a logistic model, the combination of a set of miRNAs increased the discriminatory role of CgA irrespective of PPI treatment. In pNET patients with normal CgA level our regression model yielded high (89.4%) diagnostic accuracy (AUC: 0.904, sensitivity: 66.6%, specificity: 96.5%). A set of miRNAs increased the diagnostic utility of CgA in pNET even in patients with low CgA.

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Pre-operative Diagnosis of Pancreatic Neuroendocrine Tumors with Endoscopic Ultrasonography and Computed Tomography in a Large Series

Journal of Gastrointestinal and Liver Diseases ◽

10.15403/jgld.2014.1121.253.ned ◽

2016 ◽

Vol 25 (3) ◽

pp. 317-321 ◽

Cited By ~ 16

Author(s):

Raffaele Manta ◽

Elisabetta Nardi ◽

Nico Pagano ◽

Claudio Ricci ◽

Mariano Sica ◽

...

Keyword(s):

Computed Tomography ◽

Neuroendocrine Tumors ◽

Endoscopic Ultrasonography ◽

Fine Needle Aspiration ◽

Chromogranin A ◽

Needle Aspiration ◽

Large Series ◽

Tumor Diameter ◽

Pancreatic Neuroendocrine Tumors ◽

Fine Needle

Background & Aims: Diagnosis of pancreatic neuroendocrine tumors (p-NETs) is frequently challenging. We describe a large series of patients with p-NETs in whom both pre-operative Computed Tomography (CT) and Endoscopic Ultrasonography (EUS) were performed. Methods: This was a retrospective analysis of prospectively collected sporadic p-NET cases. All patients underwent both standard multidetector CT study and EUS with fine-needle aspiration (FNA). The final histological diagnosis was achieved on a post-surgical specimen. Chromogranin A (CgA) levels were measured. Results: A total of 80 patients (mean age: 58 ± 14.2 years; males: 42) were enrolled. The diameter of functioning was significantly lower than that of non-functioning p-NETs (11.2 ± 8.5 mm vs 19.8 ± 12.2 mm; P = 0.0004). The CgA levels were more frequently elevated in non-functioning than functioning pNET patients (71.4% vs 46.9%; P = 0.049). Overall, the CT study detected the lesion in 51 (63.7%) cases, being negative in 26 (68.4%) patients with a tumor ≤10 mm, and in a further 3 (15%) cases with a tumor diameter ≤20 mm. CT overlooked the pancreatic lesion more frequently in patients with functioning than non-functioning p-NETs (46.5% vs 24.3%; P = 0.002). EUS allowed a more precise pre-operative tumor measurement, with an overall incorrect dimension in only 9 (11.2%) patients. Of note, the EUS-guided FNA suspected the neuroendocrine nature of tumor in all cases. Conclusions: Data of this large case series would suggest that the EUS should be included in the diagnostic work-up in all patients with a suspected p-NET, even when the CT study was negative for a primary lesion in the pancreas.– . Abbrevations: CgA: chromogranin A; EUS: Endoscopic Ultrasonography; FNA: fine-needle aspiration; p-NETs: pancreatic neuroendocrine tumors.

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