Pancreatic endocrine tumors

[Neuroendocrine tumors of the pancreas]

CLINICAL/METHODOLOGICAL ISSUE

Neuroendocrine tumors (NET) of the pancreas fall into the group of gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN). The assignment of imaging morphological criteria to this heterogeneous group of complex tumors is often difficult.

STANDARD RADIOLOGICAL METHODS

Diagnostic ultrasound, computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography-CT (PET/CT) are available for the detection of pancreatic NET (also referred to as NEN) and for the diagnosis of spread and the search for metastases.

METHODOLOGICAL INNOVATIONS

In particular, nuclear medicine examination methods with somatostatin analogues are of high value, since they make tumors visible with high sensitivity via radioactively labeled receptor ligands.

PERFORMANCE

CT and MRI have high detection rates of pancreatic NET. Further developments, such as diffusion imaging, have further improved these traditional cross-sectional imaging diagnostics. However, nuclear medicine methods are an important component in detection and are superior to CT and MRI.

ACHIEVEMENTS

It is important for the radiologist to be familiar with NET of the pancreas, as it is an important differential diagnosis-also with regard to prognosis-of other pancreatic lesions.

PRACTICAL RECOMMENDATIONS

Because NET are often hypervascularized, a biphasic examination technique after contrast administration is mandatory for cross-sectional imaging. PET/CT with somatostatin analogues should be performed for further diagnosis.

Epidemiological trends for functional pancreatic neuroendocrine tumors: A study combining multiple imputation with age adjustment

Purpose

The purpose of this study was to examine trends in the incidence and incidence-based (IB) mortality of functional pancreatic neuroendocrine tumors(F-PNETs), and to identify factors associated with survival times.

Methods

Data were obtained from the Surveillance, Epidemiology, and End Results database from 2000 to 2017. Trends in the age-adjusted incidence of F-PNETs and IB mortality were examined using the Joinpoint Regression Program. Statistical analyses were run using chi-square tests, Kaplan-Meier curves, and the Cox proportional hazards model. Multiple imputation was used to deal with missing data.

Results

A total of 142 patients with F-PNETs met the study inclusion criteria. It was found that the incidence of F-PNETs decreased over the study period, with an annual percent change (APC) of -2. 5% (95% CI [-4. 3, -0. 5], P<0. 05). This decrease was found to be significant for women, and also when limited to cases with distant disease or rare F-PNETs, with APCs of -4. 2% (95% CI [-7. 4, -0. 9], P<0. 05), -6. 7% (95% CI [-10. 4, -2. 8], P<0. 05), and -9. 1% (95% CI [-13. 5, -4. 4], P<0. 05), respectively. The Cox regression analysis revealed that the tumor size, tumor stage, tumor type, and surgical resection were associated with F-PNETs mortality.

Conclusions

This was the first population-based epidemiological study of F-PNETs and we found a continual decrease in the incidence of F-PNETs from 2000 to 2017. The prognosis and survival times were closely related to the calendar year at diagnosis, tumor stage, and tumor size.

Neoplasms of the Neuroendocrine Pancreas: An Update in the Classification, Definition, and Molecular Genetic Advances

This review focuses on discussing the main modifications of the recently published 2017 WHO Classification of Neoplasms of the Neuroendocrine Pancreas (panNEN). Recent updates separate pancreatic neuroendocrine tumors into 2 broad categories: well-differentiated pancreatic neuroendocrine tumors (panNET) and poorly differentiated pancreatic neuroendocrine carcinoma (panNEC), and incorporates a new subcategory of "well-differentiated high-grade NET (G3)" to the well-differentiated NET category. This new classification algorithm aims to improve the prediction of clinical outcomes and survival and help clinicians select better therapeutic strategies for patient care and management. In addition, these neuroendocrine neoplasms are capable of producing large quantity of hormones leading to clinical hormone hypersecretion syndromes. These functioning tumors include, insulinomas, glucagonomas, somatostatinomas, gastrinomas, VIPomas, serotonin-producing tumors, and ACTH-producing tumors. Although most panNENs arise as sporadic diseases, a subset of these heterogeneous tumors present as parts on inherited genetic syndromes, such as multiple endocrine neoplasia type 1, von Hippel-Lindau, neurofibromatosis type 1, tuberous sclerosis, and glucagon cell hyperplasia and neoplasia syndromes. Characteristic clinical and morphologic findings for certain functioning and syndromic panNENs should alert both pathologists and clinicians as appropriate patient management and possible genetic counseling may be necessary.