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Objective:To investigate the effect of lymph node metastasis on the prognosis of patients with G2 phase stage pancreatic neuroendocrine neoplasm(pNEN).Methods:A retrospective case control study was conducted to analyze the case data of 368 patients with pancreatic neuroendocrine tumors in G2 phase stage from January 1, 2010 to December 31, 2016 in SEER database, including 174 males and 194 females. According to whether lymph nodes were metastatic, they are divided into lymph node non metastatic (N0) group ( n=272) and lymph node metastatic (N1) group ( n=96). The Kaplan-Meier method and Log-rank test were used to compare the overall survival rate (OS) of patients in the N0 and N1 groups. The COX proportional risk model was used to evaluate whether N stage was an independent risk factor affecting prognosis. Count data were expressed as cases and percentage(%), and Chi-square test was used for comparison between the groups. Results:Among all patients, the OS of patients in the N0 group was better than that of patients in the N1 group. The OS of N0 patients at 1, 3, and 5 years was 96.3%, 92.7%, and 85.6%, respectively, while the OS of N1 patients at 1, 3, and 5 years was 92.6%, 82.1%, and 82.1%, respectively ( P=0.014). Multivariate analysis showed that age ( HR=2.245, 95% CI: 1.126-4.475, P=0.022) and N stage ( HR=0.457, 95% CI: 0.237-0.883, P=0.020) were independent prognostic factors for G2 phase pNEN patients. Conclusion:Lymph node metastasis is one of the independent prognostic factors in patients with G2 phase stage pNEN.
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On March 24, 2017, a patient with Von Hippel-Lindau syndrome (VHL) characterized by bilateral adrenal pheochromocytoma and pancreatic tumors was admitted to our hospital, who underwent simultaneous pancreatic body and tail tumor resection, bilateral adrenal tumor resection and Omentum transplantation of the right adrenal gland.Intraoperative hormone therapy was used. Part of the normal adrenal tissue was preserved and embedded in the omentum, but an adrenal crisis occurred on the first day after the operation.The hormone replacement was used. Postoperative hormone replacement therapy was performed for 6 months. After 4 years of follow-up, blood pressure was normal, no cortical dysfunction, no tumor recurrence or other related lesions appeared. The preserved part of adrenal tissue during simultaneous multi-organ tumor resection for such patients can reduce long-term hormone replacement after surgery and prevent late adrenal cortex dysfunction.
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ObjectiveTo explore the value of MSCT for differentiating the hypovascular pancreatic neuroendocrine tumors (Hypo-PNETs) from mass-forming pancreatitis.Methods21 patients with histological-confirmed MPFs and 19 patients with Hypo-PNETs who underwent preoperative dynamic contrast-enhanced CT were included. The CT images were analyzed including tumor size,density, border, CT values in each phase, dilatation of pancreatic duct and bile duct and metastases. The clinical data included age, sex and clinical symptoms.ResultsMFPs often occurred in male patient compared with Hypo-PNETs (85.7% vs 52.6%, P<0.05), and the difference is statistically significant; Metastases only occurred in Hypo-PNETs (P<0.05), and the difference is drastically significant. The well-defined margin often occurred in Hypo-PNETs (52.4% vs 47.6%, P=0.032). Solid tumor more happened in MFPs(95.2% vs 47.4%, P＜0.05). The CT values in the portal of MFPs were higher than Hypo-PNETs(P<0.05). The combined features showed accepted diagnostic performance for differentiating Hypo-PNETs from MFPs (89.5% of sensitivity and 95.2% of specificity).ConclusionMFPs often occurred in male patient, and CT values of portal phase, density, border and metastases may be valuable for differentiating Hypo-PNETs from MFPs.
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Pancreatic neuroendocrine neoplasms(pNENs)might present as part of complex hereditary(familial)syndromes caused by germline mutations such as multiple endocrine neoplasia type 1(MEN1),von Hippel-Lindau disease(VHL),tuberous sclerosis,and neurofibromatosis type1(NF1).Increasing knowledge of hereditary pNENs in both their genetic underpinnings and clinical implications has affected the entire spectrum of their surgical management.However,the appropriate surgical timing and management of concomitant pNENs inhereditary tumor syndromes is still debated.
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Objective To analyze the CT and MRI features of high and low grade pancreatic neuroendocrine tumors (PNET). Methods The clinical, imaging and pathological data of 32 patients with PNET collected from January 2011 to May 2017 were retrospectively analyzed.There were 21 cases with low grade PNET(G1,G2)and 11 cases with high grade PNET(G3).All of the 32 patients were performed with CT or MRI examination before operation,and pathology analysis was confirmed after operation.The imaging findings were compared between high-and low-grade PNET groups.Results In 32 patients,31 cases were with single lesion,only 1 case with two lesions.Twelve cases were in G1,9 cases in G2 and 11 cases in G3.Lesion location:10 lesions were in pancreatic head,10 lesions in body and 12 lesions in tail.Lesion shape:19 lesions were round,and 13 lesions were irregular.Lesion internal components:16 cases were solid lesion,14 cases were as a cystic-solid lesion and 2 cases were cystic lesion.Calcification was found in 5 cases.Pancreatic bile tract dilatation was found in 3 cases(both were G3).The other organs or lymph gland metastasis were found in 4 cases(both were G3),in which 2 cases were with liver metastasis, 2 cases with lymphatic metastasis. High-grade PNET was usually located in the head of the pancreas,tumors were large in size,and the shape was often irregular,showing low enhancement on enhanced CT or MRI, which can be accompanied by dilation of the pancreatic bile tract and other organs or lymph node metastasis. Conclusion High-grade and low-grade PNET shows certain imaging characteristics, such as tumor diameter, shape, location, internal components,enhancement pattern,pancreatic bile tract dilatation and metastases features,which has important value for the forecast of preoperative pathology grade of PNET.
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Objective: To determine whether microtubule-associated protein 2 (MAP2) and microtubule-associated protein 1B (MAP1B) could be prognostic biomarkers for patients with pancreatic neuroendocrine tumors (PNETs). Methods:With immunohisto-chemical staining, the expressions of MAP2 and MAP1B were examined in 193 and 120 primary tumors and peritumoral tissues, re-spectively. Then, the relationship between the expression of each protein and clinicopathological characteristics, including prognosis was analyzed. Results:MAP2 and MAP1B were expressed in 88 of 193 (45.6%) and 77 of 120 (64.2%) tumors, respectively. The expres-sion of MAP2 was significantly associated with the favorable overall survival of patients with PNETs (P=0.012). Moreover, MAP2 expres-sion was associated with the improved overall survival in a subset of patients with stageⅡand stageⅢtumors (P=0.017). The MAP1B expression did not correlate with other clinicopathological features and prognosis. Conclusion:MAP2 could be a novel, independent prognostcbiomarker for PNETs.
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Pancreatic neuroendocrine tumors (P-NETs) are a group of heterogeneous tumors,including functional and nonfunctional ones.With the enhancement of clinicians' awareness about this disease and the improvement of imaging diagnostic techniques,the incidence of P-NETs has obviously increased in the past years.Based on the mitotic counting and Ki-67 positive index,the grading classification is of great value for the diagnosis,treatment and even prognosis of P-NETs.P-NETs are a group of malignant tumors with inert biological behaviors,whose surgical resection rate and long-term survival is much better than those of pancreatic ductal adenocarcinoma.P-NETs have different malignant potentials.Clinicians need to develop a comprehensive treatment plan in combination with the patient's symptoms,tumor grading classification and TNM staging information.Surgery is the only curable way to cure P-NETs.Even if radical resection is not suitable,palliative surgery may alleviate the patients,symptoms,and even prolong their survival time.According to the tumor location,size,quantity,degree of grading,local invasion and distant metastasis,different surgical procedures should be selected.
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Objective: To investigate the clinical characteristics, diagnosis, treatment, and prognostic factors of pancreatic neuroendocrine neoplasms (PNENs). Methods: From August 2004 to August 2016, the clinical data of 63 patients with PNENs in the Sir Run Run Shaw Hospital, an affiliate of the Zhejiang University School of Medicine, were retrospectively analyzed. The data included age, gender, function, tumor location, tumor size, pathological characteristics, lymph nodes, metastasis, and treatment. Association of these factors with PNEN prognosis was proven by univariate analysis and multivariate analysis. Results: In our study, the patients' overall survival time was between 5 and 127 months; the median time was about 46.6 months. Moreover, the survival rates in three years and five years are 88.8％ and 84.1％ respectively. Univariate analysis showed that factors such as lymph node metastasis, liver metastasis, vascular invasion, TNM staging and pathological grading, and radical operation were associated with prognosis (P<0.05). We did not prove any of the factors to be an independent factor associated with poor short-term outcome by multivariate analysis. Conclusion: PNENs are rare low-grade malignant tumors with heterogeneity, which is why they can be erroneously diagnosed. AJCC TNM staging in 2017 and the WHO pathological classification in 2010 can actively guide the prognosis evaluation. The lymph node metastasis, liver metastasis,and vascular invasion affected the prognosis of PNENs. Patients with radical operation had improved prognosis.
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Objective To investigate the role and significance of neuropilin-2(NRP2)for regulating the angiogenesis of pancreatic neuroendocrine tumors(PNETs).Methods The NRP2 expression in pancreatic neuroendocrine tumer BON-1 cell line was intevened.The BON-1 cells cultural supernatants in the control group and interference group were used to treat human umbilical vein endothelial cells(HUVEC).CCK-8 was used to detect the cell proliferation,Transwell was used to detected the cell migration and the tubule formation test was used detect the pro-angiogenesis.Results The CCK-8 detection showed that there was no statistically significant difference in the supernatant treated HUVEC proliferations between the interference group and control group medium(P>0.05):the absorbancy in the control group was 0.35±0.04,while which in the interference group was 0.32±0.04.The Transwell test showed that the invasion ability of HUVEC treated with cultural supernatants in the interference group was weakened compared with the control group,the control group was(203±13)/hole,while the interference group was(100±10)/hole(P＜0.01);the tubule formation test showed that HUVEC tubular formation treated by cultural supernatant in the interference group was decreased,the control group was 40±5,while the interference group was 24±3(P＜0.01).Conclusion Interfering NRP2 expression of BON-1 cells can inhibit the vessel formation ability of co-cultured HUVEC,suggesting that NRP2 may have the pro-angiogenesis effect of PNETs,and may be a potential new target for the treatment of PNETs.
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[Summary] Pancreatic neuroendocrine tumors( P-NETs) is the most important cause of mortality for patients with multiple endocrine neoplasia type 1 ( MEN1 ) . Improved outcome depends on early diagnosis and optimal management. In this perspective, we are discussing the updated studies and challenges regarding as biochemical screening, tumor localization, prognosis prediction, surgery and therapy of advanced diseases.
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Objective To investigate the assessed value of tumor-associated macrophages ( TAMs ) and KIT expression for liver metastasis in pancreatic neuroendocrine tumors (PNETs) and patients′outcome. Methods A total of 79 patients who underwent surgical resection and pathologically diagnosed as PNETs in the Department of Hepatopancreatobiliary Surgery in Sun Yat-sen Memorial Hospital from January 1995 to May 2015 were enrolled.The immunohistochemical staining of CD68 and KIT were detected and the correlations with clinicopathological factors were analyzed.Results Of 79 PNETs cases, CD68 and KIT in tumor tissue were overexpressed in 30(38%) and 35(44.3%) cases, respectively.CD68 overexpression was associated with tumor infiltration ( P<0.001 ), AJCC stage 7 ( P<0.001 ), liver metastasis ( P<0.001 ) and early recurrence (P=0.019).Patients with low CD68 level had significantly better survival than those with high CD68 expression ( P=0.0002 ).KIT overexpression was correlated with WHO 2010 and AJCC stage 7 (P<0.001;P=0.002), nonfunctional status of the tumor (P=0.002) and liver metastasis (P=0.026). The survival period of patients with low KIT expression was greatly longer than those with high KIT level (P=0.0013).CD68 and KIT co-overexpression was observed in patients with tumor invasion (P<0.001), advanced WHO and AJCC stage (both P<0.001) and better prognostic survival (P=0.0057).Multivariate analysis showed that CD68 overexpression (HR:2.9;95%CI:1.16~7.23;P=0.033) was an independent prognostic factor for PNETs.Conclusions CD68 and KIT overexpression is correlated with advanced disease stage, higher risk for liver metastasis and worse survival.CD68 is an independent prognostic factor for PNETs.
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Pancreatic neuroendoerine tumors (PNET) is a complicated and heterogeneous group of neoplasia,and the incidence of PNET is growing rapidly recently.The current study on PNET lags behind what is known of other pancreatic tumors.Therefore,understanding of the molecular pathology is important for improving the early diagnosis,treatment and prognosis.With the development of molecular biology,there are already several potential targets proved to have application role in treatment of PNET.Here,the authors present the current knowledge about the molecular alterations of PNET.
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Objective To investigate the atypical CT ,MRI findings of pancreatic neuroendocrine tumors (PanNETs) ,in order to improve diagnosis .Methods The clinical ,imaging and pathological data of 6 patients with PanNETs confirmed by pathology were analyzed retrospectively .Results In all 6 cases ,2 lesions were located in the pancreatic head ,3 lesions in the pancreatic body ,and 1 lesion in the pancreatic tail .There were 2 functional PanNETs with an average size of 2 .1 cm × 2 .6 cm ,which showed homogeneous density or signal .There were 4 nonfunctional PanNETs with an average size of 2 .7 cm × 4 .3 cm ,one of which had calcification ,and two of which had obviously cystic change ,including intracapsular bleeding in one case .Contrast‐enhanced examinations showed that all 6 lesions had mild or moderate enhancement .Three lesions were manifested as relatively intense enhancement in the arterial and portal venous phase ,but decreased enhancement in the delayed phase ,including annular envelope enhancement in one case .Two le‐sions were manifested as progressive enhancement .The last case was manifested as inwardly filled enhancement .Three lesions had unclear boundaries ,while one lesion had splenic vein invasion .Two cases accompanied with mild expansion of the common bile duct or pancreatic duct .Conclusion PanNETs can be ma+nifested as atypical findings such as obviously cystic changes ,and(or) mild to moderate enhancement .It is suggested that the atypical imaging findings of PanNETs should be recognized well to improve the diag‐nostic accuracy .
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BACKGROUNDS/AIMS: Resection or enucleation is currently the treatment of choice for small pancreatic neuroendocrine tumors (NETs). Irreversible electroporation is a novel ablative method that is used for locally advanced pancreatic adenocarcinoma, but little data exists for its use for pancreatic NETs. We report an early experience of IRE for early pancreatic NETs. METHODS: Between April 2014 and March 2015, 3 patients with small (<2 cm) pancreatic NETs were treated with percutaneous IRE. RESULTS: There were no adverse effects during the procedure. Mean hospital stay was 2.6 days. All patients remained disease free on 12-19 months follow up. One patient developed recurrent pancreatitis with pseudocyst formation. CONCLUSIONS: IRE for small tumors of the pancreas is practical and may offer advantages over other thermal ablative techniques, since it preserves vital structures such as blood vessels, bile and pancreatic ducts. Further data regarding the long term disease free interval is required to establish efficacy.
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Humans , Adenocarcinoma , Bile , Blood Vessels , Electroporation , Follow-Up Studies , Length of Stay , Methods , Neuroendocrine Tumors , Pancreas , Pancreatic Ducts , PancreatitisABSTRACT
OBJECTIVE: The objective of the following study is to summarize the epidemiology of pancreatic neuroendocrine tumors (p‑NETs) in our single institution, analyze the diagnostic characteristics, share the experience of surgical treatments and discuss the prognostic factors. METHODS: A retrospective collection and analysis of clinical data of 125 patients with p‑NETs which were pathologically confirmed in our hospital from January 2002 to December 2012. RESULTS: A total of 125 patients of which 52 were males and 73 were females. Totally 92 patients had functional p‑NETs, while non‑functional p‑NETs were diagnosed in 33 patients. The most common operative procedures performed were local resection of pancreatic tumor (47.2%), followed by distal pancreatectomy (29.6%). Thirty patients (28%) had post‑operative complications, the most common of which was pancreatic fistula (22.4%). The overall survival rate at 5 years was 68.4%. The 5‑year survival rate for patients with functional tumors was 75.1%, compared with 50.0% for those with non‑functional tumors (P = 0.021). The survival time of patients with R0 resection was statistically longer than that of patients with Not R0 resection (P < 0.005). In univariate analysis, the most powerful predictors of poor outcome were gender, age, tumor size, functional status, surgical margins, lymph node invasion and distant metastasis. However only surgical margin and distant metastasis were significant predictors in multivariate analysis (P = 0.001, 0.047, respectively). CONCLUSION: p‑NETs are an uncommon and heterogeneous group of tumors, with a rising incidence. Surgery is the most effective treatment. Surgical margin and distant metastasis were the most significant prognostic factors. Radical resection should be taken more into considerations.
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Pancreatic neuroendocrine tumors(pNETs)have a low prevalence,and may be func-tional as secreting biologically active substance or nonfunctional. With the increased understanding of this disease,new technologies are being developed for diagnosis and treatment. However,surgical excision re-mains the primary therapy for localized tumors and the cure rate is not ideal yet. In choosing the appropri-ate therapy for locally advanced/ metastatic pNETs,medical management strategy should be made in a multidisciplinary context. In addition to chemotherapy,there have been significant advances in targeted mo-lecular therapy.
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Background: pancreatic neuroendocrine tumors (PNET) account for 1-2percent of pancreatic neoplasms. Its incidence has increased in recent years probably due to improved imaging studies. Aim: to analyze the clinical characteristics, surgical outcomes and overall survival of patients with PNET who underwent resective surgery. Methods: case series study. Data was collected from the central database and clinical records from patients with biopsy-proven PNET's who underwent surgical resection from june 2005 to june 2012. Results: twenty patients were included (10.6 percent of all pancreatic resections), 12 female, with a median age of 44 [20-77] years. Abdominal pain was the most common symptom. Two patients had a type 1 multiple endocrine neoplasia (MEN-1) syndrome. Pre-operative work up included CT, MR and/or PET/CT. Five patients had functional tumors. Five Whipple procedures, 14 distal pancreatectomies and 1 enucleation were performed. Among the postoperative complications, there were 5 type B and 1 type C pancreatic fistulas. There was no mortality. At 31 [5-90] month median follow-up, overall survival was 100%. Conclusion: PNETs represent an increasing reason for pancreatic resection in our center. Surgical resection of the tumor with negative microscopic margins is the treatment of choice.
Introducción: los tumores neuroendocrinos del páncreas (TNEP) representan el 1-2 por ciento de las neoplasias pancreáticas. Su incidencia ha aumentado en los últimos años debido probablemente a la mayor capacidad diagnóstica de los estudios por imágenes. Objetivos: analizar las características clínicas, resultados quirúrgicos y sobrevida alejada de los pacientes con TNEP operados en nuestro centro. Material y Métodos: estudio descriptivo de una serie de casos. Análisis de base de datos y registros clínicos de los pacientes con diagnóstico histológico de TNEP sometidos a cirugía resectiva en nuestro centro entre junio de 2005 y junio de 2012. Resultados: serie compuesta por 20 pacientes (10,6 por ciento de las resecciones pancreáticas), 12 de sexo femenino, con una mediana de edad de 44 (20-77) años. El dolor abdominal fue el síntoma de presentación más frecuente. Dos pacientes eran portadores del síndrome de neoplasia endocrina múltiple tipo 1 (NEM-1). La evaluación diagnóstica se realizó con CT, RM y/o PET/CT. Los tumores fueron funcionantes en 5 enfermos. Se realizaron 5 pancreatoduodenectomías (PD), 14 pancreatectomías corporocaudales (PC) y 1 enucleación. Entre las complicaciones postoperatorias, hubo 5 fístulas pancreáticas tipo B y una tipo C. No hubo mortalidad. En el seguimiento (mediana de 31 [5-90] meses), ningún paciente falleció por progresión de la enfermedad. Conclusión: los TNEP representan una patología en aumento en nuestro centro. La cirugía resectiva con márgenes microscópicos negativos es la alternativa terapéutica de elección.
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Humans , Male , Adult , Female , Middle Aged , Pancreatic Neoplasms/surgery , Pancreatic Neoplasms/mortality , Neuroendocrine Tumors/surgery , Neuroendocrine Tumors/mortality , Cohort Studies , Follow-Up Studies , Magnetic Resonance Imaging , Pancreatic Neoplasms/diagnosis , Positron-Emission Tomography , Postoperative Complications , Radiopharmaceuticals , Survival Analysis , Tomography, X-Ray Computed , Treatment Outcome , Neuroendocrine Tumors/diagnosisABSTRACT
Objective To investigate the clinical,pathologic and endoscopic ultrasound characteristics of pancreatic neuroendocrine tumors (PNETs).Methods Clinical data of 24 consecutive patients of PNETs who were admitted between January 2002 and January 2011 were reviewed.Results Among these 24 patients,19 were diagnosed to have insulinomas,1 was malignant insulinoma,2 were gastrinomas,and 2 were glucagonomas.Eighteen (75％) cases of PNETs were functional PNETs,and 6 (25％) were nonfunctional PNETs.The mean age of the patients was (42 ± 14) years old ranging from 19 ～ 64 years old,and the percentage of male patient was 33.3％.The main symptoms of insulinomas were intermittent abdominal pain or discomfort,and the main manifestations of glucagonomas were weight loss,skin migratory erythema; and the main symptoms of gastrinomas were diarrhea,vomiting with large amounts of water-like liquid.The detection rate of CT was 86.7％ (13/15),and the detection rate of EUS was 100％ (15/15),but PET-CT detected only 40％ of tumors (2/5).The endoscopic ultrasound characteristics of PNETs were circular or oval hypoechoic mass,and the volume was small with clear boundary and homogeneous echo.There was no enlarged lymph node,and liquid was detected in big tumor.Twenty-two patients received operation and 2 patients did not.PNETs expressed CgA and Syn protein.All patients of PNETs were alive with 7 to 80 months follow-up.Conclusions The clinical characteristics of PNETs were unique.EUS has a high accuracy for detecting and localizing PNETs.The surgical method is similar to that of pancreatic cancer,and the prognosis is relatively good.
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Objective To investigate the value of plasma chromogranin A (CgA) in the diagnosis of neuroendocrine tumors (NETs), and to evaluate the diagnostic efficacy of plasma CgA in different gastrointestinal pancreatic neuroendocrine tumors (GEP NETs). To investigate the role of monitoring plasma CgA in the progress of GEP NETs. Methods ELISA kits were used to measure the CgA plasma level in 56cases of GEP NETs, 52 cases of pheochromocytoma, and 7 cases of small cell lung cancer (SCLC) and 52cases of normal controls respectively. The sensitivity and specificity of plasma CgA in diagnosis of gastrointestinal pancreatic endocrine tumor; pheochromocytomas and SCLC were calculated. The group of GEP NETs included 13 cases of gastrointestinal carcinoid tumors, 13 cases of gastrinomas, 12 cases of islet cell tumors and 18 cases of other type tumors of GEP NETs. The differences of plasma CgA levels and various sensitivities were compared in different types tumors of GEP NETs. Meanwhile the value of plasma CgA in the diagnosis of metastatic and nonmetastatic tumors in GEP NETs was determined. Results The median CgA levels and quartile of the groups of GEP NETs, pheochromocytomas and SCLCs were 84. 5U/L and 38. 3-175.5 U/L, 154.0 U/L and 53. 3-243.8 U/L, and 55.0 U/L and 19.0-79.0 U/Lrespectively, which were significantly higher than that of ( 18. 5 U/L and 12. 3-25. 8 U/L) normal controls (P＜0. 001 ). The sensitivities of CgA in diagnosis of GEP NETs, pheochromocytomas and SCLCs were 82. 1%, 88.5% and 57. 1% respectively, and the specificities were all 96.2%. In the group of GEP NETs, the CgA level of gastrinoma was significant higher than the groups of carcinoid, islet cell tumor, and other type tumors of GEP NETs. The sensitivities of CgA in diagnosis of gastrinoma, carcinoid tumors, and islet cell tumors were 92. 3%, 84. 6% and 50. 0% respectively. In the group of GEP NETs, it showed significant differences in CgA levels in patients with metastatic and non-metastatic tumors. Conclusion The plasma CgA levels were elevated significantly in the GEP NETs, and showed a high sensitivity and specificity particularly in the diagnosis of gastrinoma. CgA also can be used as a marker in monitoring tumor development and evaluating prognosis during the clinical application.
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Objective: To study the ability of somatostatin receptor scintigraphy using Tc-99m-hydrazinonicotinyl-Tyr3-octreotide (Tc-99m-HYNIC-TOC) for localization of pancreatic neuroendocrine tumors. Methods: Five patients (3 female, 2 male; age range: 53 to 80 years; mean age: 65 years) with either histologically proven or clinically suspected insulinoma were studied. Ten mCi of Tc-99m-HYNIC-TOC were intravenously injected. Whole body scans were obtained 2 and 4 hours after injection. SPECT/CT studies of areas of interest were performed after the 4-hour whole body image. Scintigraphic findings were correlated not only with the results of conventional imaging methods, including computed tomography (CT), magnetic resonance imaging (MRI), and ultrasound but also through 1-year clinical follow-up. Results: The Tc-99m-HYNIC-TOC study showed true-negatives in two patients suspected of insulinoma proven by intraoperative ultrasound in one case and 1-year clinical follow-up with no evidence of hypoglycemia in the other patient. Abnormal Tc-99m-HYNIC-TOC accumulation was demonstrated in three patients with pancreatic tumors. Additional metastatic lesions to lung and bone were detected in one patient formerly diagnosed of malignant insulinoma with multiple liver metastases. Conclusion: Tc-99m-HYNIC-TOC SPECT/CT imaging may provide more accurate staging of pancreatic neuroendocrine tumors than conventional imaging. It is an optional technique to recruit patients for somatostatin analogs therapy.