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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

If the final pathologic examination reveals a carcinoid tumor of the kidney, additional evaluation to rule out another occult primary tumor site is necessary. If the primary origin of the tumor is confirmed to be from the kidney, additional evaluation is required for the detection of metastasis. Renal carcinoid tumors are extremely rare; however, both primary and metastatic renal carcinoid tumors have been reported. We report a case of a 40-year-old woman with primary carcinoid of the kidney and metastatic disease in the liver not evident by computed tomography and magnetic resonance imaging but identified by somatostatin receptor scintigraphy.
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PMID:Primary renal carcinoid tumor with liver metastases detected with somatostatin receptor imaging. 1588 49

Gastroenteropancreatic endocrine tumors (GEP ETs) constitute a spectrum of tumors that arise throughout the entire body but are drawn together under a common definition based on the expression of proteins derived from granules, vesicles, or both. GEP ET characterization is dependent on the primary tumor, and encompasses various factors: the WHO classification; hormone-related symptom recognition; hormone marker measurements; screening for inherited syndromes; staging; and somatostatin receptor characterization. Hypervascularization and somatostatin expression constitute major features of endocrine tumors that affect diagnosis, imaging, and therapy. GEP ET prognosis is characterized by its diversity, including a subgroup of patients with slowly progressive disease even at the metastatic stage. Prognosis assessment is mainly based on WHO classification and staging. A second cancer and cardiovascular comorbidity might also play a major prognostic part when present. Mastery of several key points analyzed in this Review, to be applied during the diagnostic and prognostic processes, is essential for defining a tailored therapeutic management.
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PMID:Gastroenteropancreatic endocrine tumors: clinical characterization before therapy. 1731 31

Carcinoid tumors are a fascinating group of neuroendocrine neoplasms that develop either sporadically or as part of an inheritable syndrome. Many tumors arise in the bronchopulmonary or gastrointestinal tract, but a neuroendocrine tumor can arise in almost any organ. The tumors have varied malignant potential depending on the site of their origin, and the clinical manifestations often are nonspecific. Metastases may be present at the time of diagnosis, which often occurs at a late stage of the disease. Imaging plays a pivotal role in the localization and staging of neuroendocrine tumors and in monitoring the treatment response. Imaging is often challenging, and a combination of anatomic and functional techniques is usually required, depending on the tumor type and location. Techniques include ultrasonography, barium studies, endoscopy, computed tomography, magnetic resonance imaging, somatostatin receptor scintigraphy, iobenguane scintigraphy, and, in select cases, positron emission tomography. Coregistration of structural and functional images is often of incremental value for accurate localization of the primary tumor and any meta-static disease. Radiologists must understand the contribution of each imaging modality in the assessment of different neuroendocrine tumors. In addition, knowledge of the optimal technique for each radiologic and radionuclide imaging examination is essential. Familiarity with the protean imaging appearances of both primary and metastatic disease is essential for accurate staging, treatment monitoring, and surveillance. Finally, an understanding of the wide variety of treatment options for patients with carcinoid tumors is vital for optimal management.
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PMID:Anatomic and functional imaging of metastatic carcinoid tumors. 1737 63

Neuroblastoma is the most common extracranial solid tumor of childhood. It commonly presents in children younger than 2 years of age, with 90% being younger than 5 years of age. There is marked variability in clinical behavior ranging from spontaneous regression or differentiation into benign tumors to rapid and progressive fatal disease. Approximately 50% of patients will have metastases at presentation. The management is dependent on age, stage of disease, and biological and biochemical markers. Nuclear medicine plays an important role in the initial staging, as a prognostic indicator, for assessment of response to treatment, and also in therapy. The most common nuclear medicine diagnostic studies are (99m)Tc-disphosphonate bone scintigraphy and (123)I-MIBG (metaiodobenzylguanidine) scintigraphy. Bone scintigraphy has been the main investigational modality to diagnose skeletal metastases. Whole body imaging with (123)I-MIBG has become the preferred diagnostic test because this agent accumulates in neuroblastoma in 90% to 95% of cases and will accumulate in the primary tumor and metastases particularly in bone, bone marrow, lymph nodes, and soft tissues. MIBG can be used to assess therapy response and is a significant prognostic indicator. Other diagnostic techniques include positron emission tomography (PET)/computed tomography, mainly using (18)F-fluorodeoxyglucose. Other more experimental PET agents, as well as radiolabeled antibodies and octreotide, also are being investigated. Therapy has mainly focused on palliation and has been used alone or in combination with chemotherapy in high-risk refractory or relapsed patients. Major attention is being placed on stratification of patients to try and reduce the side effects associated with intensive megatherapy in the low to intermediate risk patients. Neuroendocrine tumors (NETs) are rare in childhood, but nuclear medicine techniques, mainly using MIBG and somatostatin receptor agents, have a role in diagnosis, staging, and a limited role in therapy. Newer radiopharmaceuticals, including PET agents, are being evaluated for the assessment of NET. Nuclear medicine techniques play a major role in the management of neuroblastoma and NET.
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PMID:Neuroblastoma and other neuroendocrine tumors. 1754 28

The management of gastroenteropancreatic endocrine tumors is greatly linked to the localization of primary tumor. Morphological imaging methods are thus necessary. However, the expression of somatostatin receptors in endocrine tumors makes their detection possible thanks to radiolabeled somastotatin analogs. [(111)In-DTPA] octreotide is the main radiolabeled analog for somatostatin receptor scintigraphy. Positron emission tomography uses other tracers and currently allows improvement of the diagnosis and the tumoral staging. It also allows to affect the therapeutic management. A further step is about to be taken as far as the therapy of endocrine tumors is concerned with the peptide receptor radionuclide therapy. Those therapies are now being offered in some European and American centers for progressive metastatic tumors. Their place in the therapeutic strategy has to be defined, especially in comparison to targeted therapy. The sudden and delayed adverse events as well as the current legislation on the use of radioactive therapy-aimed products have limited their development in France so far.
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PMID:[Somatostatin receptor-based imaging and therapy of digestive endocrine tumors]. 2123 28

Neuroendocrine neoplasms of the digestive system represent a rare and heterogeneous group of malignancies with various clinical presentations and prognoses. The WHO classification for the year 2000 was updated in 2010 to take the histopathology and tumor biology of these tumors into account. Together with proliferation-based grading and the recently established staging system using the ENETS TNM classification, it forms the basis for the further diagnostic and therapeutic approach. Clinical presentation depends mainly on the primary site of the tumor and its functionality. Characteristic symptoms are seen only rarely, this being the reason these tumors are usually detected at an advanced stage. Approximately 30% of GEP-NEN are hormonally active and can cause a specific clinical syndrome. In addition to these specific hormones, chromogranin A is considered the most accurate general marker for the biochemical follow-up of these patients. In addition to commonly used radiological and endoscopic imaging modalities, somatostatin receptor-based functional imaging using either octreotide scintigraphy or novel PET-based techniques with specific isotopes such as Ga68-DOTA-octreotate play a crucial role in the detection of the primary tumor as well as in the evaluation of tumor extent and the selection of patients for receptor-based radionuclide therapy.
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PMID:[Neuroendocrine neoplasms of the gastrointestinal tract. Classification, clinical presentation and diagnosis]. 2229 Mar 17

Neuroendocrine neoplasms are a rare and heterogeneous group of diseases that account for only 2% of all gynecologic malignancies. The most common types are ovarian carcinoid tumor and small cell neuroendocrine carcinoma of the cervix. The tumors are staged according to FIGO clinical staging system. The diagnosis is usually made retrospectively after obtaining the results of histopathological evaluation of the primary tumor They rarely cause syndromes related to hormone overexpression. Neuroendocrine neoplasms are characterized by aggressive behaviour Even at an early stage there is high incidence of nodal and distant metastases. Survival is poor regardless of stage at diagnosis. The most important is to diagnose the neuroendocrine tumor accurately and treat it in multimodal, aggressive approach to control the disease better and reduce the incidence of reccurences. Apart from typical therapeutic approach, treatment may encompass isotope therapy using radiolabeled somatostatin analogs. This method should be reserved for patients with expression of somatostatin receptors detected by the somatostatin receptor scyntygraphy. Data concerning the management of neuroendocrin tumors are based mainly on retrospective studies and clinical case series. Lack of randomized trials makes it impossible to select the best treatment option. Better understanding of the biology of neuroendocrine tumors, especially the molecular genetics, will in the future help to determine the optimal treatment strategies for these tumors.
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PMID:[Contemporary management of neuroendocrine neoplasms of the female genital organs]. 2237 29

Neuroendocrine neoplasms (NEN) occur in the entire gastrointestinal tract. The updated classification of the WHO (2010) and current TNM-classification provide a basis for the therapeutic decision and assess the prognosis. Endoscopy and different imaging techniques are important for the localization of the primary tumor as well as local and distant metastases. The most important diagnostic imaging technique is somatostatin receptor scintigraphy. Therapeutic strategy should be discussed within the scope of a multidisciplinary tumor board. Surgery of NEN is the sole curative option. The treatment options for liver metastases include surgical resection as well as radiofrequency ablation and hepatic artery embolization. In advanced stage, systemic therapy should be used. Recent studies demonstrated a significantly prolonged progression-free survival using octreotide in well differentiated NEN. Besides the well established steptozotocine based chemotherapy regimens for pancreatic NEN, novel agents such as the mTOR-inhibitor everolimus and multityrosine kinase inhibitor sunitinib have recently also shown a prolonged progression-free survival. Moreover, temozolomide-based chemotherapy appears to be effective in pancreatic NEN. Finally, somatostatin receptor targeted radionuclide therapy can be effective in progressing gastroenteropancreatic NEN.
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PMID:[Gastroenteropancreatic neuro-endocrine neoplasms]. 2302 85

Inhibition of mTOR is commonly considered a valid target in cancer treatment, but this assertion does not address effects on the immune microenvironment that may be detrimental to cancer treatment. Here we show how administration of the mTOR inhibitor RAD001 (everolimus) results in the occurrence of distant metastasis in a rat model of pancreatic cancer. RAD001 was administered twice weekly for 4.5 weeks as a single treatment or combined with [(177)Lu-DOTA,Tyr3]octreotate ((177)Lu-DOTATATE), where the latter targets the somatostatin receptor-2. The hypothesized synergistic therapeutic effect of RAD001 combined with (177)Lu-DOTATATE was, however, not observed in our experiments. The combination was shown to be less effective than (177)Lu-DOTATATE alone. Unexpectedly, tumor metastasis was observed in 77% of the subjects treated with RAD001, either alone or as part of the combination treatment. This was a striking effect, because metastasis did not occur in control or (177)Lu-DOTATATE-treated animals, including those where the primary tumor was surgically removed. These findings may be important clinically among noncompliant patients or patients that discontinue RAD001 therapy because of adverse effects.
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PMID:mTOR inhibitor RAD001 promotes metastasis in a rat model of pancreatic neuroendocrine cancer. 2314 18

Neuroendocrine tumors constitute a heterogeneous group of neoplasms arising from the cells of the neural crest. We present a rare case of primary sinonasal neuroendocrine carcinoma in a 61-year-old male patient where somatostatin receptor PET/CT with 68Ga-DOTANOC correctly delineated the extent of primary tumor as compared to contrast-enhanced CT, thereby changing patient management.
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PMID:68Ga DOTANOC PET/CT for accurate delineation of disease extent in a case of sinonasal small cell neuroendocrine carcinoma. 2360 89


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