Gastroenteropancreatic Neuroendocrine Tumors: Role of Imaging in Diagnosis and Management
ABSTRACT Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are a heterogeneous group of neoplasms that arise from cells of the diffuse neuroendocrine system and are characterized by a wide spectrum of clinical manifestations. All NETs are potentially malignant but differ in their biologic characteristics and the probability of metastatic disease. The pathologic classification of these tumors relies on their proliferation and differentiation. In the past decades, several nomenclatures have been proposed to stratify neuroendocrine tumors, but the World Health Organization classification is the one that is most widely accepted and used. The diagnosis of neuroendocrine tumor relies on clinical manifestation, laboratory parameters, imaging features, and tissue biomarkers in a biopsy specimen. With improved understanding of the natural history and lesion biology, management of GEP-NETs has also evolved. Although surgery remains the only potentially curative therapy for patients with primary GEP-NETs, other available treatments include chemotherapy, interferon, somatostatin analogs, and targeted therapies. Recent improvements in both morphologic and functional imaging methods have contributed immensely to patient care. Morphologic imaging with contrast agent-enhanced multidetector computed tomography and magnetic resonance imaging is most widely used for initial evaluation and staging of disease in these patients, whereas functional imaging techniques are useful both for detection and prognostic evaluation and can change treatment planning. ©RSNA, 2013.
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ABSTRACT: Pancreatic endocrine tumors (PETs) are rare neoplasms of this organ. The majority of PETs are tumors without hormonal activity. In this publication, we present the diagnostic and therapeutic guidelines for the management of these tumors proposed by the Polish Network of Neuroendocrine Tumors. These guidelines refer to biochemical and location diagnostics, including scintygraphy of somatostatin receptors, endoscopic ultrasonography and other anatomical and functional imaging methods. High importance is attached to correct histopathological diagnosis which determines further management of patients with PETs. Antitumor therapy requires multidirectional procedure, and therefore the rules of surgical treatment, biotherapy, chemotherapy and peptide receptor radionuclide therapy are discussed.Endokrynologia Polska 01/2013; 59(1):68-86. DOI:10.5603/EP.2013.0031 · 1.21 Impact Factor
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ABSTRACT: Midgut neuroendocrine tumors (MNETs) are rare, and the primary tumor is usually small and difficult to visualize at imaging. Patients often present late with extensive liver and nodal metastases and may experience symptoms secondary to the release of active substances by the primary tumor, such as serotonin and its metabolites, which have local and systemic effects. Locally, this causes desmoplasia and vascular encasement and may lead to small bowel obstruction and ischemia, with significant morbidity and mortality. Systemically, the release of active substances into the circulation can cause flushing, diarrhea, and abdominal pain (carcinoid syndrome); these substances can be detected in urine and blood serum and used as markers for diagnosis and treatment follow-up. MNETs retain expression of specific peptide receptors such as somatostatin receptors, which will bind to synthetic somatostatin analogs such as octreotide. This feature is useful for functional imaging of patients with MNETs and for peptide receptor radionuclide therapy using somatostatin analogs. Resection of the primary tumor is advocated, even in patients with extensive metastases, because it may prevent development of local complications, can help control systemic symptoms, and has been shown to confer some survival advantage. Computed tomography and functional imaging are used to identify the primary tumor and assess its resectability. The main factors governing resectability are patient comorbidities (eg, carcinoid heart disease), vascular involvement, and desmoplasia. © RSNA, 2014.Radiographics 03/2014; 34(2):413-26. DOI:10.1148/rg.342135504 · 2.73 Impact Factor
- Journal of endocrinological investigation 07/2014; 37(9). DOI:10.1007/s40618-014-0119-0 · 1.55 Impact Factor