MULTIHORMONAL ISLET CELL CARCINOMAS IN THREE KOMODO DRAGONS (VARANUS KOMODOENSIS).

Multihormonal pancreatic islet cell carcinomas were found in one female and two male captive geriatric Komodo dragons (Varanus komodoensis). Gross changes in the pancreas were visible in two of the cases. Clinical signs noted in the Komodo dragons were lethargy, weakness, and anorexia. Histologically, the tumors were comprised of nests and cords of well-differentiated neoplastic islet cells with scant amounts of eosinophilic cytoplasm and round, euchromatic nuclei, with rare mitoses. Infiltration by the islet cell tumor into the surrounding acinar tissue was observed in all cases, but no metastatic foci were seen. Multihormone expression was observed in all tumors, which labeled strongly positive for glucagon and somatostatin and focally positive for polypeptide. Pancreatic islet cell neoplasms should be considered in the differential diagnosis for geriatric Komodo dragons presenting with weakness, lethargy, and poor appetite.

Population-level analysis of pancreatic neuroendocrine tumors 2 cm or less in size.

BACKGROUND: There is a paucity of evidence regarding incidence and predictors of survival in pancreatic neuroendocrine tumors (PNETs)≤2 cm in size. METHODS: Patients having undergone resection for nonfunctioning PNETs were selected from the SEER database (1988-2009) and an institutional pathology database (1996-2012). PNETs≤2 cm were compared with PNETs>2 cm. Data were analyzed with χ2 tests, ANOVA, the Kaplan-Meier method, log rank tests, and Cox proportional hazard, and binary logistic regression. RESULTS: The incidence of PNETs≤2 cm in the United States has increased by 710.4% over the last 22 years. Rates of extrapancreatic extension, nodal metastasis, and distant metastasis in PNETs≤2 cm in the SEER database were 17.9, 27.3, and 9.1%, respectively. The rate of nodal metastasis in our institutional series was 5.7%. Disease-specific survival at 5, 10, and 15 years for PNETs≤2 cm was 91.5, 84.0, and 76.8%. Decreased disease-specific survival was not associated with nodal metastasis, but rather with high grade [moderately differentiated, hazard ratio (HR) 37.2, 95% confidence interval (CI) 2.7-518.8; poorly differentiated, HR 94.2, 95% CI 4.9-1,794.4; reference, well differentiated], and minority race (Asian, HR 30.2, 95% CI 3.1-291.7; Black, HR 60.1, 95% CI 2.1-1,027.9; reference, White). CONCLUSIONS: Pancreatic neuroendocrine tumors≤2 cm are increasingly common, and the most significant predictors of disease-specific survival are grade and race. The SEER database excludes PNETs considered to be benign, and rates of extrapancreatic extension, nodal metastasis, and distant metastasis are overestimated. Small size, however, does not preclude malignant behavior.

Differential regulation of telomerase activity and telomerase RNA during multi-stage tumorigenesis.

Telomeres consist of short repeated sequences that are synthesized by telomerase, a ribonucleo-protein DNA polymerase. Telomerase activity is present in many tumours and not detected in many normal tissues. Telomere shortening in human and mouse tissues and primary cell cultures may be due to the absence of telomerase activity. To determine when telomerase is activated during tumour development and progression, we examined telomerase activity and expression of the recently cloned mouse telomerase RNA component (mTR) in two different transgenic mouse models of multi-stage tumorigenesis. These mouse models allow examination of many independent tumours from genetically identical individuals. These mice reproducibly develop pancreatic islet cell carcinoma and squamous cell carcinoma of the skin. In both carcinoma types, we detected telomerase activity only in late-stage tumours; in contrast, we found mTR levels were upregulated in the early preneoplastic stages, and further increased during progression. Surprisingly, mTR levels did not parallel the amount of telomerase activity detected and a subset of tumours lacked telomerase activity and yet expressed telomerase RNA. Regulation of telomerase activity may therefore be separable from expression of its RNA component. These results clearly demonstrate telomerase is activated in late stages of tumour progression, and show for the first time that the initial up regulation of telomerase RNA is an early event, concurrent with the hyperproliferation elicited by viral oncogenes.

Survival impact of malignant pancreatic neuroendocrine and islet cell neoplasm phenotypes.

BACKGROUND: The low incidence of malignant "functional" (F) or "nonfunctional" (NF) neuroendocrine islet cell tumors (ICTs) of the pancreas represents a challenge to precise post-therapeutic survival prediction. This study examined the survival impact of malignant pancreatic ICT morphologic subtypes. METHODS: A pancreatic ICT data set was created from a US-based population database from 1980-2004. Prognostic factors with survival impact and relationships between surgical therapy and overall survival (OS) were analyzed. RESULTS: There were 2,350 individuals with malignant ICTs. Histologic subtypes included carcinoid tumors, islet cell carcinomas, neuroendocrine carcinomas, and malignant gastrinomas, insulinomas, glucagonomas, or VIPomas. There was no difference in resection rates between FICTs and NFICTs (23% vs. 20%, P = ns). Median OS was 30 months, with group differences ranging from NE carcinomas (21) to VIPomas (96; P < 0.0001). Median OS of resected versus unresected FICTs was 172 versus 37 months, while that of NFICTs was 113 versus 18 months (P < 0.0001). Compared to neuroendocrine carcinomas, hazard ratios were: VIPomas 0.48, gastrinomas 0.65, carcinoid tumors 0.76, insulinomas 0.84, glucagonomas 0.93, and islet cell carcinomas 1.0. CONCLUSIONS: When controlled for other established prognostic parameters, histopathologic subtype assignment of pancreatic ICTs affects survival prediction. Resection is associated with superior survival for all tumor types.

Cathepsin cysteine proteases are effectors of invasive growth and angiogenesis during multistage tumorigenesis.

Tumors develop through successive stages characterized by changes in gene expression and protein function. Gene expression profiling of pancreatic islet tumors in a mouse model of cancer revealed upregulation of cathepsin cysteine proteases. Cathepsin activity was assessed using chemical probes allowing biochemical and in vivo imaging, revealing increased activity associated with the angiogenic vasculature and invasive fronts of carcinomas, and differential expression in immune, endothelial, and cancer cells. A broad-spectrum cysteine cathepsin inhibitor was used to pharmacologically knock out cathepsin function at different stages of tumorigenesis, impairing angiogenic switching in progenitor lesions, as well as tumor growth, vascularity, and invasiveness. Cysteine cathepsins are also upregulated during HPV16-induced cervical carcinogenesis, further encouraging consideration of this protease family as a therapeutic target in human cancers.

Xenon-inhalation computed tomography for noninvasive quantitative measurement of tissue blood flow in pancreatic tumor.

BACKGROUND AND AIMS: The purpose of this prospective study was to demonstrate the ability to measure pancreatic tumor tissue blood flow (TBF) with a noninvasive method using xenon inhalation computed tomography (xenon-CT) and to correlate TBF with histological features, particularly microvascular density (MVD). METHODS: TBFs of pancreatic tumors in 14 consecutive patients were measured by means of xenon-CT at diagnosis and following therapy. Serial abdominal CT scans were obtained before and after inhalation of nonradioactive xenon gas. TBF was calculated using the Fick principle. Furthermore, intratumoral microvessels were stained with anti-CD34 monoclonal antibodies before being quantified by light microscopy (×200). We evaluated MVD based on CD34 expression and correlated it with TBF. RESULTS: The quantitative TBF of pancreatic tumors measured by xenon CT ranged from 22.3 to 111.4 ml/min/100 g (mean ± SD, 59.6 ± 43.9 ml/min/100 g). High correlation (r = 0.885, P < 0.001) was observed between TBF and intratumoral MVD. CONCLUSION: Xenon-CT is feasible in patients with pancreatic tumors and is able to accurately estimate MVD noninvasively.

Prognostic relevance of survivin in pancreatic endocrine tumors.

BACKGROUND: Better prognostic markers are needed for pancreatic endocrine tumors. Survivin is an apoptosis inhibitor that is suggested to have a negative prognostic impact in several tumor types. Contradictory data exist, especially regarding the significance of a nuclear versus cytoplasmic location of survivin. The prognostic relevance of nuclear and cytoplasmic survivin expression in pancreatic endocrine tumors-controlled for the tumor Ki-67 index, World Health Organization classification, and TNM stage-was investigated. METHODS: A total of 111 patients treated at a tertiary referral center were retrospectively evaluated. Clinical data were gathered from medical records. Immunohistochemistry for survivin and Ki-67 was performed on paraffin-embedded tissue. Univariate and multivariate Cox analyses were performed. RESULTS: Patients with tumors that had <5% survivin-positive nuclei had a mean survival of 225 months [95% confidence interval (CI) 168-281]. The corresponding figure for patients with 5 to 50% survivin-positive tumor cell nuclei was 101 months [95% CI 61-140; hazard ratio (HR) 2.4; P < 0.01) and with >50% survivin-positive nuclei 47 months (95% CI 24-71; HR 4.9; P < 0.001). Nuclear survivin expression in >50% of the tumor cells was an independent marker of a poor prognosis (HR 5.7; P < 0.01). Cytoplasmic survivin was not a significant prognostic factor in the multivariate analysis (HR 0.94; P = 0.90). CONCLUSIONS: High expression of nuclear survivin is a significant marker of a poor prognosis in patients with a pancreatic endocrine tumor.

Proceedings of the 2010 National Toxicology Program Satellite Symposium.

The 2010 annual National Toxicology Program (NTP) Satellite Symposium, entitled "Pathology Potpourri," was held in Chicago, Illinois, in advance of the scientific symposium sponsored jointly by the Society of Toxicologic Pathology (STP) and the International Federation of Societies of Toxicologic Pathologists (IFSTP). The goal of the annual NTP Symposium is to present current diagnostic pathology or nomenclature issues to the toxicologic pathology community. This article presents summaries of the speakers' presentations, including diagnostic or nomenclature issues that were presented, along with select images that were used for voting or discussion. Some topics covered during the symposium included a comparison of rat and mouse hepatocholangiocarcinoma, a comparison of cholangiofibrosis and cholangiocarcinoma in rats, a mixed pancreatic neoplasm with acinar and islet cell components, an unusual preputial gland tumor, renal hyaline glomerulopathy in rats and mice, eosinophilic substance in the nasal septum of mice, INHAND nomenclature for proliferative and nonproliferative lesions of the CNS/PNS, retinal gliosis in a rat, fibroadnexal hamartoma in rats, intramural plaque in a mouse, a treatment-related chloracne-like lesion in mice, and an overview of mouse ovarian tumors.

Concurrent insulinoma and pancreatic adenocarcinoma: report of a rare case and review of the literature.

Pancreatic adenocarcinoma is the 5th leading cause of cancer-related death in Western countries and insulinomas are rare endocrine neoplasms of the pancreas. The concurrent appearance of pancreatic adenocarcinoma and insulinoma is very rare and to the best of our knowledge has never been reported again. Herein, we present such an occurrence in a 74-year-old man. Resection of a mass in the uncinate process of the pancreas revealed pancreatic adenocarcinoma with severe desmoplastic reaction. Two years later, due to symptomatology persistence the patient was re-examined and a new 2 cm mass in the uncinate process was found leading to surgery, which demonstrated a 2 cm endocrine islet-cell tumor. Establishing a diagnosis in patients with insulinoma is difficult and the imaging studies still have low sensitivity and specificity except for intra-operative ultrasonography, which is the most accurate method detecting 90% of these lesions.

Nonfunctioning pancreatic endocrine tumor with extension into the main pancreatic duct: report of a case.

Pancreatic endocrine tumors (PETs) rarely involve the main pancreatic duct. We report a case of malignant nonfunctioning pancreatic endocrine tumor (NFPET) with prevalent intraductal growth. A 47-year-old woman was referred to us after ultrasonography at a routine health check showed diffuse swelling of the pancreas. Preoperative imaging showed a solid mass in the tail of the pancreas and a bulging intraductal mass in the main pancreatic duct. We performed total pancreatectomy because the tumor occupied almost the entire lumen of the main pancreatic duct. Histological examination confirmed well-differentiated endocrine carcinoma. We review reported cases of the intraductal growth of NFPETs and discuss the pathogenesis of these unusual tumors.

A bioluminescent mouse model of pancreatic {beta}-cell carcinogenesis.

The Rip1Tag2 transgenic mouse model of pancreatic beta-cell carcinogenesis has been instrumental in identifying several hallmarks of cancer, including tumor cell evasion from apoptosis, tumor angiogenesis and tumor invasion. Moreover, Rip1Tag2 mice have been helpful in the development and testing of innovative cancer therapies and tumor imaging protocols. However, based on tumor localization in the mouse, primary tumor growth and metastatic dissemination cannot be easily monitored in a longitudinal axis by non-invasive and low-technology approaches. Here, we report the generation of a new transgenic mouse line as a versatile tool to study beta-cell carcinogenesis. Transgenic expression of a bicistronic messenger RNA encoding simian virus large T antigen and firefly luciferase in pancreatic beta-cells recapitulates insulinoma development in a reproducible multistage process. In the mouse line called RipTag-IRES-Luciferase line (RTL) 1, the beta-cell-specific expression of luciferase allows the non-invasive monitoring of primary tumor growth over time in vivo and the detection and quantification of disseminated tumor cells and micrometastases in distant organs ex vivo. When crossed to mouse lines in which the expression of cancer 'modifier' genes has been manipulated, tumor initiation and tumor progression are similarly affected as previously reported for Rip1Tag2 mice, indicating a robust tumor progression pathway shared between the two different transgenic mouse lines. Together, the data indicate that the RTL1 mouse line will be of great value to study anti-tumoral therapeutic approaches as well as to define the functional roles of cancer- and metastasis-related genes when crossed to appropriate transgenic or gene-targeted mouse lines.

Clinicopathological features of pancreatic endocrine tumors: a prospective multicenter study in Italy of 297 sporadic cases.

OBJECTIVES: Information on pancreatic endocrine tumors (PETs) comes mostly from small, retrospective, uncontrolled studies conducted on highly selected patients. The aim of the study was to describe the clinical and pathological features of PETs in a prospective, multicenter study. METHODS: Newly diagnosed, histologically proven, sporadic PETs observed from June 2004 to March 2007 in 24 Italian centers were included in a specific data set. RESULTS: Two hundred ninety-seven patients (mean age 58.6+/-14.7 years, females 51.2%, males 48.8%) were analyzed. In 73 cases (24.6%), the tumor was functioning (F) (53 insulinomas, 15 gastrinomas, 5 other syndromes) and in 232 (75.4%) it was non-functioning (NF); in 115 cases (38.7%), the diagnosis was incidental. The median tumor size was 20 mm (range 2-150). NF-PETs were significantly more represented among carcinomas (P<0.001). Nodal and liver metastases were detected in 84 (28.3%) and 85 (28.6%) cases, respectively. The presence of liver metastases was significantly higher in the NF-PETs than in the F-PETs (32.1% vs. 17.8%; P<0.05), and in the symptomatic than in the asymptomatic patients (34.6% vs. 19.1%; P<0.005). At the time of recruitment, the majority of patients (251, 84.5%) had undergone surgery, with complete resection in 209 cases (83.3%). CONCLUSIONS: This study points out the high number of new cases of PETs observed in Italy, with a high prevalence of NF and incidentally discovered forms. The size of the tumor was smaller and the rate of metastasis was lower than usually reported, suggesting a trend toward an earlier diagnosis.

Usefulness of EUS combined with contrast-enhancement in the differential diagnosis of malignant versus benign and preoperative localization of pancreatic endocrine tumors.

BACKGROUND: Pancreatic endocrine tumors (PETs) develop in relatively few patients, but they are often difficult to diagnose because of their small size and various clinical symptoms. OBJECTIVE: The aim of this study was to investigate the usefulness of EUS combined with contrast enhancement (CE-EUS) in the preoperative localization of PETs and the differentiation between malignant and benign PETs. DESIGN AND SETTING: Single-center retrospective study. PATIENTS: Sixty-two pathologically certified PETs of 41 patients who underwent EUS, multiphasic multidetector computed tomography (MDCT), and transabdominal US at our institute since 2001. INTERVENTIONS: Intravenous injection of US contrast media. MAIN OUTCOME MEASUREMENTS: Comparison of EUS, MDCT, and US in the preoperative identification of PETs, and the characteristic findings of EUS with malignancy. RESULTS: EUS showed high sensitivity (95.1%) in identifying PETs compared with MDCT (80.6%) and US (45.2%). Multivariable logistic regression analysis showed that heterogeneous ultrasonographic texture was the most significant factor for malignancy (OR = 53.33; 95% CI, 10.79-263.58). Most heterogeneous hypoechoic areas and anechoic areas corresponded to hemorrhage or necrosis on pathologic examination. They were identified as filling defects in CE-EUS and were more clearly recognized than in conventional EUS. LIMITATIONS: Retrospective study. CONCLUSION: EUS has higher sensitivity in preoperative localization of PETs compared with MDCT and US. The characteristics of EUS and CE-EUS findings in malignant PETs were clarified, and they will improve the diagnostic accuracy of PETs.

Pancreatic endocrine tumors: radiologic-clinicopathologic correlation.

Pancreatic endocrine tumors (PETs) are primarily well-differentiated tumors composed of cells that resemble normal islet cells but that arise from pancreatic ductal cells. They are classified as functioning or nonfunctioning according to their associated clinical symptoms; insulinoma, gastrinoma, and glucagonoma are the most common functioning PETs. They also are classified according to their biologic behavior, although all PETs have malignant potential. Most are sporadic, but some are associated with familial syndromes such as multiple endocrine neoplasia type 1, von Hippel-Lindau syndrome, and neurofibromatosis type 1. At imaging, PETs typically appear as well-defined hypervascular masses, a finding indicative of their rich capillary network. Cystic change, calcification, and necrosis are common in large tumors, which are associated with a poorer prognosis and a higher prevalence of local and vascular invasion and metastases than are smaller tumors. Even when metastases are present, many well-differentiated PETs have an indolent course. Poorly differentiated PETs are rare and have an infiltrative appearance; patients with such tumors have a poor prognosis. Knowledge of the characteristic clinical, pathologic, and radiologic features of PETs is important in the evaluation and management of patients with a suspected clinical syndrome or a pancreatic mass.

Cell adhesion molecule 1 is a novel pancreatic-islet cell adhesion molecule that mediates nerve-islet cell interactions.

BACKGROUND & AIMS: Cell adhesion molecule 1 (CADM1), mediates nerve-mast cell attachment and communication through homophilic binding. An immunohistochemical screen showed that CADM1 is expressed in pancreatic islets. Here, we determined the cell types expressing CADM1 and examined its role in nerve-islet cell interactions. METHODS: Immunohistochemistry and double-staining immunofluorescence were performed on murine and human pancreases and on islet cell tumors (ICTs). alphaTC6 cells, a murine alpha cell line, were cultured on neurite networks of superior cervical ganglia. Neurite-alphaTC6 cell attachment and communication were examined after nerves were activated specifically by scorpion venom. RESULTS: CADM1 was expressed on the plasma membrane in all 4 major types of islet cells, alpha, beta, D, and pancreatic polypeptide in human beings, but primarily in alpha cells in mice. In cocultures, alphaTC6 cell to neurite attachment was inhibited dose-dependently by an anti-CADM1 function-blocking antibody. In response to scorpion venom-evoked nerve activation, 36% of the alphaTC6 cells mobilized Ca(2+), and introduction of a CADM1-targeting small interfering RNA reduced the fraction of responding cells to 7%. In 21 human ICTs, CADM1 was present in the plasma membrane of 7, and the others were negative for CADM1. Six of the CADM1-expressing tumors were functional hormonally, whereas all but 2 of the CADM1-negative tumors were nonfunctional (P = .0032). CONCLUSIONS: CADM1 is a novel islet cell adhesion molecule mediating nerve-islet cell interactions. The strong correlation between CADM1 expression and hormonally functional phenotypes suggests that CADM1 is involved in hormone secretion from ICTs.

Effects of angiogenesis inhibitors on multistage carcinogenesis in mice.

Solid tumors depend on angiogenesis for their growth. In a transgenic mouse model of pancreatic islet cell carcinogenesis (RIP1-Tag2), an angiogenic switch occurs in premalignant lesions, and angiogenesis persists during progression to expansive solid tumors and invasive carcinomas. RIP1-Tag2 mice were treated so as to compare the effects of four angiogenesis inhibitors at three distinct stages of disease progression. AGM-1470, angiostatin, BB-94, and endostatin each produced distinct efficacy profiles in trials aimed at preventing the angiogenic switch in premalignant lesions, intervening in the rapid expansion of small tumors, or inducing the regression of large end-stage cancers. Thus, anti-angiogenic drugs may prove most efficacious when they are targeted to specific stages of cancer.

Pancreatic endocrine tumor EUS-guided FNA DNA microsatellite loss and mortality.

BACKGROUND: The clinical course of pancreatic endocrine tumors (PET) depends on tumor size, the presence of invasion or metastasis, the Ki-67 index, mitoses per high power field, and mutational damage. Most of this information is not available before surgery for clinical decision making or prognostication. OBJECTIVE: To evaluate PET EUS-guided FNA (EUS-FNA) microsatellite loss analysis in the context of PET-related mortality. DESIGN: A single institution retrospective cohort. PATIENTS: Patients with PET diagnosed by EUS-FNA who underwent DNA microsatellite loss analysis and at least 1 year of follow-up or subsequent death. INTERVENTION: PET microsatellite loss analysis results and current clinical status were compared. RESULTS: Twenty-nine patients were included in the final analysis; the mean age of the patients was 57 years, and 10 were women (35%). The mean follow-up was 33.7 months (median 30 months, range 2-66 months). Twelve patients had disease progression, and 8 died, all from disease-specific causes. Malignant PET contained multiple microsatellite losses, with a median fractional allelic loss (FAL) of 0.37 (range 0.12-0.69, interquartile range [IQR] 0.23-0.42), significantly different from benign PET, median FAL 0 (range 0-0.18, IQR 0-0.08, P < .0001). Survival analysis revealed a significant difference in disease recurrence or progression at 2 years (P < .0001) and in the 5-year survival between patients with FAL 0.2 (P < .0001). Logistic regression could not be performed because of the perfect association between an FAL >0.2 and disease status or mortality. LIMITATIONS: Retrospective design, referral bias, and DNA analysis availability. CONCLUSIONS: PET EUS-FNA microsatellite loss analysis provides preoperative prognostic information. An FAL >0.2 is not only associated with disease progression but also with mortality.

EUS-FNA predicts 5-year survival in pancreatic endocrine tumors.

BACKGROUND: Pancreatic endocrine tumors (PETs) differ in clinical behavior and prognosis. Determination of malignant potential through specimens obtained by EUS-FNA can help in the management of these patients. OBJECTIVE: To determine the value of EUS-FNA for diagnosing PETs and for classifying their underlying malignant potential based on the World Health Organization (WHO) classification. DESIGN: Single-center, retrospective, cohort study. SETTING: Tertiary referral hospital. PATIENTS: This study involved 86 consecutive patients (44 men, mean age 58 +/- 14 years) who had been diagnosed with PETs and submitted to EUS-FNA from January 1999 to August 2008. INTERVENTION: EUS-FNA of a pancreatic mass and/or a metastasis site. Immunohistochemistry on microbiopsies or on monolayer cytology was routinely used. The lesions were classified as recommended by the WHO. MAIN OUTCOME MEASUREMENTS: EUS-FNA sensitivity and 5-year survival rate. RESULTS: Overall, in 90% (77 of 86) of patients in this study, PET was diagnosed with EUS-FNA. The sensitivity did not vary with tumor size, type, location, or the presence of hormonal secretion. Of 86 patients, 30 (35%) were submitted to surgical resection. The kappa correlation index between the WHO classification obtained by EUS-FNA and by surgery was 0.38 (P = .003). Major discrepancies were found in the group of patients diagnosed with endocrine tumor of uncertain behavior by EUS-FNA, because 72% turned out to have well-differentiated endocrine carcinoma. Sixteen patients (27%) died during a mean follow-up period of 34 +/- 27 months. The 5-year survival rates were 100% for endocrine tumors, 68% for well-differentiated endocrine carcinomas, and 30% for poorly differentiated endocrine carcinomas (P = .008, log-rank test). LIMITATIONS: Retrospective design, selection bias, and small sample size. CONCLUSIONS: This largest single-center experience to date demonstrated the accuracy of EUS-FNA in diagnosing and determining the malignant behavior of PETs. EUS-FNA findings predict 5-year survival in patients with PETs.

Neuroendocrine tumors of the pancreas.

Pancreatic endocrine tumors are rare neoplasms accounting for less than 5% of pancreatic malignancies. They are broadly classified into either functioning tumors (insulinomas, gastrinomas, glucagonomas, VIPomas, and somatostatinomas) or nonfunctioning tumors. The diagnosis of these tumors is difficult and requires a careful history and examination combined with laboratory tests and radiologic imaging. Signs and symptoms are usually related to hormone hypersecretion in the case of functioning tumors and to tumor size or metastases with nonfunctioning tumors. Surgical resection remains the treatment of choice even in the face of metastatic disease. Further development of novel diagnostic and treatment modalities offers potential to greatly improve quality of life and prolong disease-free survival for patients with pancreatic endocrine tumors.

An unusual mixed tumor of the pancreas: sonographic and MDCT features.

CONTEXT: Mixed tumors of the pancreas are exceedingly rare. CASE REPORT: We herein report on a 54-year-old female who presented with an enlarging cystic lesion in the head of the pancreas. Right upper quadrant ultrasound and multidetector-row CT scan showed a well-defined unilocular cystic tumor located in the head of the pancreas and surrounded, in part, by a hypervascular solid mass. CONCLUSION: Although mixed exocrine/endocrine pancreatic tumors have been described previously, to the best of our knowledge, this is the first case of a pancreatic mixed intraductal papillary mucinous neoplasm/endocrine tumor with illustration of its ultrasound and CT features. Moreover, the importance of preoperative analysis of imaging features in the assessment of pancreatic neoplasms is discussed.