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Arterial enhancement is the commonly described characteristic of canine insulinomas in contrast-enhanced computed tomography (CECT). However, this finding is also reported as inconsistent. The main aim of this single-center retrospective observational study was to describe the contrast enhancement (CE) pattern of canine presumed and confirmed insulinomas and presumed metastases in three consecutive (early, mid, and late) arterial phases. Included dogs had a medical-record-based clinical or cytological/histopathological diagnosis of insulinoma and quadruple-phase CECT. The arterial phases were identified according to published literature. The arterial enhancement of confirmed and presumed lesions was assessed using a visual grading score. Twelve dogs with a total of 17 pancreatic nodules were analyzed. Three dogs had multiple pancreatic nodules and nine had solitary findings. Four insulinomas were histopathologically confirmed. Late arterial phase (LAP) images demonstrated the largest number of pancreatic nodules reaching the highest enhancement scores (n = 13, 76%). All analyzed dogs had CT evidence of arterially enhancing nodules in the liver (n = 12), seven in the hepatic, splenic, or colic lymph nodes, and three in the spleen. Three out of five sampled livers and three lymph nodes were metastatic. All sampled spleens were benign. Avid arterial enhancement was the most dominant feature of canine presumed and confirmed insulinomas and presumed metastases in quadruple-phase CECT. The highest enhancement scores were observed primarily in LAP, followed by MAP. Authors, therefore, recommend including LAP in the standard CT protocol for dogs with suspected pancreatic insulinomas., (© 2023 The Authors. Veterinary Radiology & Ultrasound published by Wiley Periodicals LLC on behalf of American College of Veterinary Radiology.)

An ~10-y-old male sheep had anorexia and progressive weight loss for ~1 mo. The sheep was emaciated, and 20 d later, became recumbent and lethargic, and was hypoglycemic (0.33 mmol/L; RI: 2.6-4.4 mmol/L). The sheep was euthanized because of poor prognosis, and submitted for autopsy. We found no gross lesions in the pancreas; however, histologically, focal proliferations of round-to-polygonal cells were separated by connective tissue into small nests. These proliferating cells, which had abundant eosinophilic-to-amphophilic cytoplasm and hyperchromatic nuclei, were immunopositive for insulin and negative for glucagon and somatostatin; the lesion was diagnosed as an insulinoma. Insulinoma has not been reported previously in sheep, to our knowledge. In addition, autopsy and histologic examination revealed the presence of an adrenocortical carcinoma with myxoid differentiation and a thyroid C-cell carcinoma. Our case indicates that multiple endocrine neoplasms can occur in sheep, as in other animal species.

Background: Information regarding serum insulin concentration in dogs newly diagnosed with insulinoma and its association with clinical stage and survival time is lacking., Objective: Examine association between serum insulin concentration and survival and clinical disease stage in dogs with insulinoma., Animals: Fifty-nine client-owned dogs with a diagnosis of insulinoma from 2 referral hospitals., Method: Retrospective observational study. The χ 2 test was used to compare the proportion of dogs with increased insulin concentration in groups with or without metastasis at the time of diagnosis. Linear mixed-effect models were built to compare differences in insulin concentration between dogs with and without evidence of metastasis at the time of original diagnosis. Cox's proportional hazards regression and Kaplan-Meier graphs were used to evaluate the association between insulin concentration and insulin groups and survival., Results: Median serum insulin concentration was 33 mIU/L (range, 8-200 mIU/L) in dogs with World Health Organization (WHO) stage I disease and 45 mIU/L (range, 12-213 mIU/L) in dogs with WHO stage II and III disease. No difference was found in the proportion of dogs with increased insulin concentration with or without metastasis (P = .09). No association was identified between insulin concentration and survival (P = .63), and between dogs grouped by insulin concentration and survival (P = .51)., Conclusions and Clinical Importance: Serum insulin concentrations were not different between dogs with or without metastasis at diagnosis. The degree of insulinemia does not provide further information regarding the stage of the disease and is not associated with survival time in dogs with insulinoma., (© 2023 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objective: To report the clinical signs, histopathology results, and prognostic factors for outcomes following excision for feline insulinoma (INS)., Study Design: Retrospective study., Sample Population: Twenty client-owned cats., Methods: Medical records from 2006 to 2020 were reviewed by Veterinary Society of Surgical Oncology members for cats with hypoglycemia resulting from INS, with surgical excision and follow up. Clinical signs and histopathology results were summarized. Factors potentially related to disease-free interval (DFI), disease-related death (DRD), and overall survival time (OST) were analyzed with a Cox proportional hazards regression analysis., Results: All cats were hypoglycemic on presentation with neurologic signs in 18 out of 20 and inappropriate insulin levels in 12/13. Excision of insulinomas resulted in immediate euglycemia or hyperglycemia in 18 cats. Eighteen cats survived to hospital discharge. The median time to death or last postoperative follow up was 664 days (range: 2-1205 days). Prognostic factors included age at presentation (for DFI); time to postoperative euglycemia (for DRD); preoperative and postoperative serum blood glucose concentrations; metastasis at the time of surgery (DFI and DRD), and histopathologic tumor invasion (for OST). The median OST for all cats was 863 days. The 1-, 2- and 3-year survival rates were 75%, 51%, and 10%, respectively., Conclusion: Excision of insulinoma resulted in euglycemia or hyperglycemia in most cats. Negative prognostic factors included young age, low serum glucose concentrations, metastasis at time of surgery, tumor invasion, and shorter time to euglycemia., Clinical Significance: Surgical excision resulted in survival times comparable to those of canine INS., (© 2022 The Authors. Veterinary Surgery published by Wiley Periodicals LLC on behalf of American College of Veterinary Surgeons.)

Objective: To evaluate whether intraoperative detection of rising levels of blood glucose could improve the completeness of resection of insulin-secreting tumor tissue and whether this improves long-term outcomes., Animals: 11 client-owned dogs diagnosed with insulinoma., Procedures: Retrospective review of medical records of dogs undergoing partial pancreatectomy as treatment for insulinoma. A blood glucose reading was obtained at induction, following removal of the pancreatic mass and/or after each suspected metastatic lesion until blood glucose had normalized. Disease-free interval and survival time were measures of outcome., Results: A positive increase in blood glucose was detected in all cases, with a mean rise of 6.35 ± 4.5 mmol/L. Mean follow-up was 611 days, mean disease-free interval was 382 days, and median survival time was 762 days. Tumor stage was not associated with outcome. Three cases underwent a second surgery (metastasectomy), achieving further prolongation of disease-free survival., Clinical Relevance: A sustained increase in intraoperative blood glucose provided the surgeon with confidence of more complete resection of insulinoma tissue and resulted in improved outcomes in all cases included in this study. Subsequent metastasectomy of recurrent insulinoma lesions also provided good outcomes. Intraoperative monitoring of blood glucose during surgical treatment of insulinoma resulted in the surgeon continuing to explore and resect abnormal tissue until an increase of glycemia was observed. This was shown to provide the surgeon with more confidence of resection of all active insulinoma tissue and improved clinical outcomes.

Background: Contrast-enhanced ultrasound (CEUS) features of pancreatic lesions are poorly reported in veterinary literature., Methods: Qualitative and quantitative features of pancreatic benign (nodular hyperplasia [NH], cyst and abscess) and malignant (adenocarcinoma and insulinoma) lesions during B-mode and CEUS examinations are described in 75 dogs., Results: Adenocarcinomas (n = 23) had mixed echogenicity at B-mode, and they were hypoenhancing or non-enhancing at CEUS, with a non-homogeneous and cystic enhancement pattern. Insulinomas (n = 23) appeared as hypoechoic lesions at B-mode, and as hyperenhancing, homogeneous and solid lesions at CEUS. NH (n = 17) had an constant appearance, being hypoechoic at ultrasound (US) and isoenhancing at CEUS. Cysts (n = 7) were all anechoic, with acoustic enhancement clearly detectable at US, but were non-enhancing at CEUS. Lastly, abscesses (n = 5) had mixed echogenicity, and they showed both hyperenhancement and non-enhancement at CEUS. Hypoenhancement and non-homogeneous appearance had a moderate diagnostic accuracy in the detection of adenocarcinomas. In particular, hyperenhancement was evident only in malignant lesions (adenocarcinomas and insulinomas)., Conclusion: CEUS, in combination with B-mode US features, is a valuable tool for distinction of benign and malignant abnormalities of the pancreas and can potentially differentiate insulinomas from adenocarcinomas., (© 2022 The Authors. Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association.)

We report a rare case of functional insulinomas in a 16.7-year-old female Rhesus macaque (Macaca mulatta) that was presented with neuroglycopenic signs to the breeding colony hospital at the Tulane National Primate Research Center. At initial and follow-up examinations, the animal was consistently hypoglycaemic and was clinically maintained with additional fruits, other high-sugar food items and dextrose supplementation. Occasional episodes of seizure and collapse resolved quickly on administration of high-sugar food items. At necropsy, the uncinate process of the pancreas had a 2.2 cm diameter, red, round, firm neoplastic mass, and another neoplasm was identified on histological examination of the head of pancreas. Histologically, neoplastic cells exhibited neuroendocrine packeting, resembled pancreatic islet cells and immunolabelled for chromogranin A, synaptophysin and insulin but not for somatostatin, gastrin or pancreatic polypeptide. A few cells immunolabelled for glucagon. The clinical signs and gross and histological findings were consistent with functional insulinomas., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

An 11-year-old neutered male Domestic Shorthair cat presented with a 3-month history of hypoglycemia, two episodes of seizure, and intermittent tick-like signs. Serum biochemistry revealed severe hypoglycemia associated with high insulin concentrations. Dynamic abdominal computed tomography (CT) indicated two pancreatic masses, which were enhanced most during the late arterial phase but had different degrees and variations of attenuation. Partial pancreatectomy was performed. Histopathology and immunohistochemistry confirmed that one mass was an insulinoma and the other was an ectopic splenic tissue, consistent with the differences in imaging findings. When an intrapancreatic lesion with hyper-attenuation on dynamic abdominal CT is detected, not only insulinoma or metastasis of malignancies but also intrapancreatic accessory spleen (IPAS) should be considered as differential diagnoses.

Objectives: Canine insulinomas are uncommon malignant functional pancreatic neuroendocrine tumours with a high metastatic rate. Diagnostic imaging aids with staging and surgical planning of these tumours; however, identification is unpredictable across modalities. High-grade human pancreatic neuroendocrine tumours display increased avidity on 18 F-fluorodeoxyglucose positron emission tomography-CT., Materials and Methods: Dogs with clinicopathologic findings consistent with pancreatic insulinoma were prospectively enrolled. Patients underwent 18 F-fluorodeoxyglucose positron emission tomography-CT and CT angiography, followed by exploratory laparotomy., Results: Three patients met the inclusion criteria and had histologically confirmed insulinomas. Both metastatic lesions in patient 1 were mildly avid (SUV max 2.79 and 3.01). In patient 2, the primary pancreatic insulinoma was minimally avid (SUV max 2.16). The primary pancreatic lesion in patient 3 had similar avidity to normal pancreatic parenchyma (SUV max 1.54) and was undetected on 18 F-fluorodeoxyglucose positron emission tomography-CT. Insulinomas demonstrated variable attenuation and contrast enhancement patterns on CT angiography and certain lesions were more conspicuous than on 18 F-fluorodeoxyglucose positron emission tomography-CT. Two metastatic lesions not visible on either imaging modality were discovered in patient 2 at surgery., Clinical Significance: Canine insulinomas were inconsistently avid on 18 F-fluorodeoxyglucose positron emission tomography-CT. This finding is likely attributable to the confounding clinicopathological features and multifaceted transformation of these tumours, in addition to the influence of variable tumour size, composition and vascularity. Unpredictable tumoural avidity limits the value of 18 F-fluorodeoxyglucose positron emission tomography-CT for staging canine insulinomas., (© 2021 British Small Animal Veterinary Association.)

A 9.5 yr old Yorkshire terrier presented with chronic intermittent vomiting and lethargy of 1.5 yr duration that progressed to generalized weakness. Insulin:glucose ratio was consistent with an insulinoma. Triple-phase computed tomography revealed a mid-body pancreatic nodule. The mid-body pancreatic nodule was enucleated; histopathology was consistent with an insulinoma. Two weeks after the operation, the dog presented for anorexia and diarrhea. Abdominal ultrasound revealed a thick-walled cystic lesion along the dorsal stomach wall. An intramural gastric pseudocyst was diagnosed via exploratory laparotomy and intraoperative gastroscopy. Comparison of amylase and lipase levels of the cystic fluid with that of concurrent blood serum samples confirmed the lesion was of pancreatic pseudocyst origin. The gastric pseudocyst was omentalized. Two weeks after the operation, the dog re-presented for anorexia, regurgitation, and diarrhea. An intramural duodenal pseudocyst was identified and treated with a duodenal resection and anastomosis. The dog has remained asymptomatic and recurrence free based on serial abdominal ultrasounds 22 mo following insulinoma removal. To our knowledge, this phenomenon of pancreatic pseudocysts forming in organs other than the pancreas has not been reported in dogs. This case report and comprehensive human literature review purpose is to raise awareness of this disease process in dogs., (© 2022 by American Animal Hospital Association.)

Canine insulinoma has historically been associated with a poor prognosis; however, prolonged survival times have recently been reported. Prognostic indicators that are available preoperatively are of limited predictive accuracy, and consensus on post-operative treatment recommendations is lacking. The objectives of this study were to describe outcomes in dogs with insulinoma treated surgically, and to assess whether selected potential risk factors are strongly associated with outcomes after surgery. Medical records of two institutions were searched for dogs with insulinoma that were treated surgically. Forty-nine dogs were included. Thirty-nine dogs (80%) had immediate resolution of hypoglycaemia and 10 (20%) remained persistently hypoglycaemic postoperatively. The median survival time (MST) for all dogs was 561 days. The MST for dogs that had resolution of hypoglycaemia was 746 days. The median of the overall euglycaemic time (times from surgery to first detection of hypoglycaemia at any time point after surgery) for all dogs was 424 days. Forty-four percent of those that had resolution of hypoglycaemia experienced recurrence of hypoglycaemia by 2 years postoperatively. Pathological stage was a predictor of persistent post-operative hypoglycaemia which, in turn, was a predictor of survival time. These results show that dogs with insulinoma can have prolonged survival, and that pathological stage is a predictor of outcome., (© 2020 John Wiley & Sons Ltd.)

Objectives: To review the clinical findings and outcome in dogs diagnosed with insulinoma, and to assess which factors are predictors of overall survival. Additionally, to describe the neurological manifestations of this population and their correlation with survival., Materials and Methods: Retrospective multicentric study of canine insulinoma cases (2009 to 2020). Signalment, clinical history, neurological examination, diagnostic findings, treatment and outcome were obtained from clinical records. Univariate and multivariate analyses were used to compare the overall survival., Results: One hundred and sixteen cases were included. Median duration of clinical signs before presentation was 1.5 months. The most common presenting clinical signs were weakness (59.5%), epileptic seizures (33.6%) and changes in consciousness or behaviour (27.6%). Three dogs were suspected to have paroxysmal dyskinesia. Thirty-two dogs had an abnormal neurological examination, most commonly showing obtundation (28.1%), decreased withdrawal reflexes (21.9%) and absent menace response (18.8%). Overall survival for dogs undergoing surgery (20 months) was significantly longer than in medically treated (8 months; adjusted hazard ratio: 0.33; 95% confidence interval: 0.18, 0.59). Presence of metastases was the only other variable associated with prognosis (adjusted hazard ratio 1.72; 95% confidence interval: 1.02, 2.91)., Clinical Significance: Clinical signs of canine insulinoma are vague and non-specific. Weakness, epileptic seizures and changes in mentation or behaviour were the most commonly reported. Obtunded mentation and forebrain neurolocalisation were the main neurological manifestations. Dogs undergoing surgery had a longer overall survival compared to medically treated cases, and dogs with metastasis had a shorter overall survival regardless of treatment modality. Abnormalities in the neurological examination did not correlate with prognosis., (© 2021 The Authors. Journal of Small Animal Practice published by John Wiley & Sons Ltd on behalf of British Small Animal Veterinary Association.)

Objectives: To further evaluate the appearance of insulinoma in dogs on dual-phase CT angiography, given the disparity of findings in recent publications. To establish whether CT angiographic localisation of insulinoma correlates with surgical findings., Materials and Methods: Single centre study of dogs with a final diagnosis of insulinoma which underwent abdominal CT angiography. Scans were retrospectively re-evaluated for specific features by two board-certified veterinary radiologists. These findings were also subsequently compared to surgical and histopathological reports to determine the accuracy of lesion localisation on CT., Results: Thirty-five cases were included in final analysis, with pancreatic nodules identified in 33. Twenty-one were confirmed as insulinoma with histopathology. Jack Russell Terriers were over-represented. Twenty of 21 cases with confirmed insulinoma and 27 of 33 overall showed hyperattenuation in the arterial phase. The mean size of pancreatic insulinoma on CT was 15.1 mm, and 18.2% were larger than 20 mm. Eighteen of 21 confirmed and eight of 12 suspected insulinomas caused a deformation of the pancreatic shape, with two only identified as a result of this feature as these lesions were isoattenuating throughout the study. Pancreatic insulinoma location at surgery matched that described on the CT images in 17 of 19 cases where location was described in the surgical report., Clinical Significance: In contrast to recent publications, this study suggests hyperattenuation of insulinomas in the arterial phase is a predominant feature, and that hypoattenuation or isoattenuation are much less common. CT angiography is accurate in prediction of lesion location before surgery in most cases., (© 2021 The Authors. Journal of Small Animal Practice published by John Wiley & Sons Ltd on behalf of British Small Animal Veterinary Association.)

Aims: To compare survival in dogs with recurrent or metastatic insulinomas that were treated with palliative therapy, alone or in combination with toceranib phosphate and to assess tolerability of the combined therapy in dogs., Materials and Methods: Dogs diagnosed with insulinoma were retrospectively identified in the records of the Veterinary Teaching Hospital Complutense (Madrid, Spain). Diagnosis of insulinoma was based on clinical signs of hypoglycaemia, concentrations in serum of glucose <3.3 mmol/L and insulin >10 μIU/mL and presence of a pancreatic mass on diagnostic imaging. Dogs were treated surgically or medically, according to clinical stage established by imaging techniques, and monitored with blood and urine analyses monthly and abdominal ultrasonography every 3 months until death. Dogs that presented with metastatic disease at diagnosis or with recurrent hypoglycaemia after surgery were treated, according to the owner's decision, with one of two treatment protocols: palliative therapy alone (control group, n=7: diet, prednisone, famotidine or omeprazole, ±octreotide) or palliative therapy in combination with toceranib (treatment group, n=5; median dose of toceranib 2.52 mg/kg). Overall survival time (OST) and adverse events were compared between the two treatment groups., Results: The OST was longer in the treatment group (median 399, min 125, max 476 days) compared to the control group (median 67, min 23, max 387 days; p=0.042). Dogs in the treatment group had a higher incidence of grade 1-2 gastrointestinal toxicity (diarrhoea) than dogs in the control group (p=0.010). In all cases, gastrointestinal toxicity was solved by temporarily discontinuing toceranib., Conclusions and Clinical Relevance: The use of toceranib combined with palliative treatment in dogs with suspect metastatic or recurrent insulinomas increased survival time and was adequate tolerated.

Objective: To develop a technique for isolation and culture of canine insulinoma cells and assess expression of cellular hexokinases (glucokinase and hexokinase I) and expression and secretion of insulin from these cells in vitro., Sample: Pancreatic insulinomas and normal pancreatic tissue from 4 and 3 dogs, respectively., Procedures: Tissues were collected by surgical excision or at necropsy. Insulinoma cells from 2 dogs were cultured for up to 10 weeks with standard techniques; insulin synthesis in vitro was confirmed by immunohistochemical analysis of freshly prepared slides of cultured cells, and insulin secretion was assessed by measurement of insulin concentrations in culture medium with an ultrasensitive mouse insulin ELISA. Expression of cellular hexokinases in insulinomas and adjacent normal (nontumor) pancreatic tissue from the same dog (n = 3) was examined by quantitative reverse transcriptase PCR assay., Results: Insulinoma cells survived for up to 10 weeks but did not proliferate in culture. Insulin was detected in isolated cells and secreted into culture medium for up to 10 weeks. Both cellular hexokinases were expressed; glucokinase appeared to be overexpressed in insulinomas, compared with normal pancreatic tissue from the same dogs., Conclusions and Clinical Relevance: Canine insulinomas expressed hexokinases responsible for glucose responsiveness. Insulinoma cells were successfully maintained in short-term culture; cultured cells remained functional for 10 weeks as evidenced by cellular insulin content and had detectable secretion of insulin into the culture medium for ≥ 5 weeks. Apparent glucokinase overexpression by insulinomas suggested a possible mechanism underlying excessive insulin release by these tumors.

Insulinomas (INS) are the most common human and canine functioning pancreatic neuroendocrine tumours. The long-term prognosis for malignant INS is poor, because micrometastases are frequently missed during surgery. As human and canine malignant INS share clinical and histopathological features, dogs have been proposed as models for INS research. Using RNA-sequencing, we conducted a pilot study to better understand the underlying molecular mechanisms of canine INS. Normal canine pancreas and lymph node control tissues were compared with primary INS and INS-metastatic lymph nodes, revealing more than 3,000 genes differentially expressed in normal pancreas compared to primary INS. Only 164 genes were differentially expressed between primary INS and INS-metastatic lymph nodes. Hierarchical clustering analysis demonstrated similar genetic profiles in normal pancreas and early clinical stage primary INS, whereas late clinical stage primary INS resembled the genetic profile of INS-metastatic lymph nodes. These findings suggest that markers of malignant behaviour could be identified at the primary site of the disease. Finally, using the REACTOME pathways database, we revealed that an active collagen metabolism, extracellular matrix remodelling, beta-cell differentiation and non-beta-cell trans-differentiation might cause disease progression and hyperinsulinism in INS, identifying major pathways worthy of future research in this currently poorly controlled disease.

Background: Information regarding outcome of dogs undergoing surgical management for insulinoma is based on studies of a small number of dogs., Objectives: To report the outcomes of dogs undergoing surgery as treatment for insulinoma, the prevalence of postoperative diabetes mellitus (DM) in this group and to determine if development of DM can be predicted., Animals: Forty-eight client-owned dogs, with a histopathological diagnosis of insulinoma, from three European referral hospitals., Methods: Retrospective observational study. Dogs were identified from a search of electronic hospital records. Cox's regression was used to determine factors associated with postoperative survival and relapse, and logistic regression was used to determine factors associated with the development of DM., Results: Median survival time (MST) was 372 days (range 1-1680 days), with dogs with stage I disease having the longest survival time. Stage I dogs had MST of 652 days (range 2-1680 days), whereas dogs with either stage II or III disease had MST of 320 days (range 1-1260 days; P = 0.045). Postoperative hyperglycemia was identified in 33% (16/48) of the dogs, of which 9 (19% of the total population) developed persistent DM. No factors that could be used as predictors for development of DM were identified., Conclusions and Clinical Importance: Stage of disease and postoperative hypoglycemia were associated with greater odds of relapse and decreased survival time; these could be used when discussing prognosis. In this study, postoperative DM developed more commonly than previously reported, but no factors were identified that might be useful predictors., (© 2020 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.)

The objective of this study was to determine risk factors for vomiting and inappetence and evaluate long-term outcome after surgical treatment of pancreatic β-cell tumors in dogs. Records of 33 dogs that underwent surgery for such tumors were retrospectively evaluated. Inappetence and vomiting occurred in 27.3% and 24.2% of dogs, respectively. Risk factors for postoperative vomiting were longer duration of clinical signs before surgery, higher preoperative total protein concentration, and lack of liver metastasis. No significant risk factors for inappetence or survival were identified. Median survival time was 723 days. Dogs with a longer duration of clinical signs before surgery may have had greater pancreatic involvement or more pronounced systemic perturbations. Higher preoperative total protein concentration may reflect preoperative dehydration or inflammation. Significance of lack of liver metastasis is unknown. The long survival time indicates a good overall prognosis with surgical treatment, justifying surgical intervention in patients with advanced disease., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Clinical and imaging diagnosis of canine insulinomas has proven difficult due to nonspecific clinical signs and the small size of these tumors. The aim of this retrospective case series study was to describe MRI findings in a group of dogs with pancreatic insulinomas. Included dogs were presented for suspected pancreatic insulinoma, MRI was used to assist with localization of the primary lesion, and the diagnosis was confirmed with surgical exploratory laparotomy and histopathology. The MRI studies for each dog were retrieved and the following data were recorded: T1-weighted and T2-weighted signal intensities, type of contrast enhancement, size and location of the primary lesion, and characteristics of metastatic lesions (if present). A total of four dogs were sampled. In all patients, the insulinoma displayed high-intensity signal on T2-weighted fat saturation images, similar to human studies. On postcontrast T1-weighted fat saturation images, the tumors were primarily isointense to normal pancreatic tissue, in contrast to human studies where a low-intensity signal is typically identified. Abnormal islet tissue was detected with MRI in all four dogs and metastases were identified in three dogs. Variations in the MRI appearance of primary and metastatic lesions were identified and could have been related to the variation of tissue composition, including the presence of neoplastic cells, hemorrhage, and fibrovascular stroma, and to the transformation of this tissue throughout the disease process., (© 2019 American College of Veterinary Radiology.)

Canine insulinoma is a highly metastatic neoplasm that is associated with a guarded to poor prognosis in dogs with distant metastases. A median survival of 6 mo has been reported for dogs with metastatic insulinoma. The dog in this report, diagnosed with stage III pancreatic insulinoma, had long-term glycemic control with survival of over 24 mo while receiving prednisone and toceranib phosphate after partial pancreatectomy. Toceranib phosphate has been shown to be an efficacious therapy for canine mast cell tumors with increasing evidence that it may be beneficial in the medical management of neuroendocrine tumors.

Objectives: To determine 1) the sensitivity of contrast-enhanced CT (CECT) for detection of primary canine insulinomas and metastases 2) the sensitivity of CECT to locate canine insulinomas within the pancreas and 3) the CECT attenuation pattern of canine insulinomas and post-contrast phase in which insulinomas have the best visibility., Methods: A retrospective review was performed of the medical records of 27 canine insulinoma patients. Simultaneous occurrence of blood glucose < 3.5 mmol/L (reference interval: 4.2-5.8 mmol/L) and plasma insulin > 10 mIU/L (reference interval: 1.4-24.5 mIU/L) were considered diagnostic for insulinoma. The dogs had a mean age of 9.0 ± 1.7 (SD) years and comprised 11 males and 17 females., Results: Using CECT-scans, 26/27 insulinomas were successfully detected. However, CECT-scans predicted the correct location of insulinomas within the pancreas in only 14/27 dogs. In 9/13 inaccurately located insulinoma cases, the location error was major. There was no significant difference between triple, double and single-phase CECT-scans with location accuracies of 54%, 50% and 50%, respectively. Also, there was no specific post-contrast phase in which insulinomas could be visualised best. Detection of lymph node metastases with CECT-scans had a sensitivity of 67% (10/15 lymph node metastases). Detection of liver metastases had a sensitivity of 75% (6/8 liver metastases). This study highlights that major location errors mainly occurred if single- or double-phase CECT-scans were used (6/9 cases)., Conclusion: It is suggested that triple-phase CECT-scans have superior outcome over single- or double-phase CECT-scans in pre-operative imaging of canine insulinomas.

Laparoscopic partial pancreatectomy has been performed in experimental canine studies and has been evaluated in human medicine but has not been reported in a clinical veterinary case. The authors present a 9 yr old field spaniel with weakness and hypoglycemia with insulin levels and Amended Insulin: Glucose Ratio results equivocal for a pancreatic insulinoma. Multiple abdominal ultrasounds did not detect the tumor, yet dual-phase computed tomographic angiography revealed the presence of a focal hypoattenuating nodule in the left lobe of the pancreas. A 3-port laparoscopic approach to the abdomen confirmed a 1.5-cm mass in the mid-left limb of the pancreas, and resection of the mass was performed with a bipolar vessel-sealing device. The surgery was performed without complication, and the dog became normoglycemic within 4 hr following surgery. Final histopathology results revealed pancreatic neuroendocrine carcinoma of the β cells. Recurrence of hypoglycemia was noted 18 mo postoperatively; however, repeat computed tomographic angiography did not reveal pancreatic abnormalities and fine needle aspirates of liver nodules did not suggest metastatic disease. Medical management was elected and the patient was euthanized 28 mo after surgery due to refractory hypoglycemic seizures.

Insulinoma is a functional, insulin-secreting tumor, arising from the beta islet cells of the pancreas. It is one of the most common neoplasms in ferrets and has been associated with clinical signs of hypoglycemia, such as ptyalism, pawing at the mouth, seizures, lethargy, and coma. The ultrasonographic features of insulinoma in ferrets have not been previously reported. The purpose of this retrospective case series study was to describe the ultrasonographic features of confirmed insulinoma in a group of ferrets. Inclusion criteria were abdominal ultrasound examination and histological confirmed insulinoma by surgical biopsy. Six ferrets met the inclusion criteria, all of which had multiple hypoglycemic episodes. Ultrasonographic images were reviewed and the characteristics of the pancreatic nodules were recorded. Twenty-eight pancreatic nodules were observed in the six ferrets and were primarily hypoechoic (89.3%, 25/28) and homogenous (46.4%, 13/28) with a smooth margin (78.6%, 22/28). The distribution of the pancreatic nodules was 46.4% in the left lobe, 50% in the right lobe, and 3.6% in the body of the pancreas. The sizes of the pancreatic nodules varied from 1.5 × 1.5 to 4.1 × 5.6 mm. All of the pancreatic nodules removed from surgery were histopathologically confirmed as insulinoma. The findings indicated that insulinoma in ferrets could be detected through ultrasonography, which may facilitate diagnosis and preoperative surgical planning., (© 2017 American College of Veterinary Radiology.)

Little information is available regarding triple-phase computed tomography (CT) of canine pancreatic insulinoma. A few case reports with small numbers of cases have indicated that hyper-attenuation in the arterial phase was a common finding on multi-phasic CT in dogs with insulinoma. Our purpose was to clarify the characteristic findings of dogs with insulinoma on triple-phase CT. Nine dogs with insulinoma that underwent triple-phase CT were included in the present study. Attenuation patterns in the arterial phase indicated hypo-attenuation in 4 cases and hyper-attenuation in 2 cases. In the remaining 3 cases, 1 case showed hypo-attenuation and 1 case showed hyper-attenuation in the pancreatic phase, and 1 case presented hyper-attenuation in the later phase. Altogether, 5 cases showed hypo and 4 cases showed hyper-attenuation in at least one phase. The enhancement pattern was homogenous in 7 cases and heterogeneous in 2 cases. Tumor margins were well-defined in 5 cases and ill-defined in 4 cases. Capsule formation was present in 5 cases and absent in 4 cases. In conclusion, it is important to note that hypo-attenuation was as common as hyper-attenuation in dogs with insulinoma in triple-phase CT in at least one phase. Additionally, mass lesions were most conspicuous not only in the arterial phase but in the pancreatic and later phases in some cases. Therefore, it is important to perform triple-phase CT and notice about variable findings for the detection of canine pancreatic insulinoma.

Functional endocrine tumours have long been thought to be rare in guinea pigs, although conditions such as hyperthyroidism and hyperadrenocorticism have been documented with increasing frequency so the prevalence of hormonal disorders may have been underestimated. Both the clinical signs and diagnosis of hyperthyroidism in guinea pigs appear to be very similar to those described in feline hyperthyroidism, and methimazole has been proven to be a practical therapy option. Hyperadrenocorticism has been confirmed in several guinea pigs with an adrenocorticotropic hormone stimulation test using saliva as a non-invasive sample matrix; trilostane has been successfully used to treat a guinea pig with hyperadrenocorticism. Insulinomas have only rarely been documented in guinea pigs and one animal was effectively treated with diazoxide., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Case Description: A 3-year-old female domestic ferret (Mustela putorius furo) with an insulinoma was treated because of a hypoglycemic crisis prior to scheduled pancreatectomy with concurrent nodulectomy., Clinical Findings: Previously, the ferret had clinical signs of lethargy and hind limb weakness; at that time, blood glucose concentration was low, and a tentative diagnosis (subsequently confirmed) of insulinoma was made. Prednisolone treatment (0.3 mg/kg [0.14 mg/lb], PO, q 12 h) did not improve clinical signs; the dosage was gradually increased over a 1-month course (1.8 mg/kg [0.82 mg/lb], PO, q 12 h) and maintained for 10 days. Overall, the treatment was ineffective, and the ferret remained lethargic and developed inappetence. At a reevaluation, the ferret had severe weakness and nonresponsiveness nearing a comatose state. Standard treatment with dextrose (1 mL of 50% solution, IV), and dexamethasone (1 mg/kg [0.45 mg/lb], SC) was administered with resultant improvement in mentation. The ferret was discharged from the hospital and then returned 3 days later for stabilization prior to pancreatectomy with concurrent nodulectomy., Treatment and Outcome: The day before surgery, the ferret was administered a glucagon constant rate infusion at a rate of 15 ng/kg/min (6.8 ng/lb/min), which resulted in an increase in blood glucose concentration to a euglycemic state and resolution of clinical signs of hypoglycemia., Clinical Relevance: As illustrated by the case described in this report, a glucagon constant rate infusion can be used successfully for the emergency treatment of hyperinsulinemic-hypoglycemic crisis in insulinomic ferrets.

Abdominal ultrasonography is one of the most common diagnostic imaging modalities used for dogs with suspected insulinoma; however, pancreatic masses are clearly identified in fewer than half of affected dogs and benign pancreatic nodules can be difficult to differentiate from malignant ones. The purpose of this prospective study was to describe contrast-enhanced ultrasonography (CEUS) characteristics of confirmed pancreatic insulinoma in a group of dogs. Inclusion criteria were as follows: (1) repeated hypoglycemia (blood glucose levels <60 mg/dl, twice or more); (2) elevated blood insulin levels with hypoglycemia; (3) pancreatic nodules detected with conventional ultrasonography; and (4) histological confirmation of pancreatic islet cell carcinoma. Immediately following conventional ultrasonography of the entire abdomen, CEUS of the pancreatic nodule and adjacent parenchyma was performed using contrast-specific technology pulse inversion imaging and perflubutane microbubble contrast agent. Three dogs met inclusion criteria. Pancreatic nodules in all the three dogs became more clearly demarcated after injection of the contrast agent. Each nodule showed different enhancement patterns: markedly hyperechoic for 5 s, slightly hyperechoic for 1 s, and clearly hypoechoic for over 30 s. These results were not in complete agreement with previously reported CEUS findings in human patients with insulinoma. All nodules were surgically resected and histopathologically confirmed as malignant insulinomas. Findings from the current study indicated that contrast-enhanced ultrasound may help to increase conspicuity of pancreatic insulinomas in dogs and that enhancement characteristics may be more variable in dogs than in humans., (© 2014 American College of Veterinary Radiology.)

A 13-year-old female Boer goat with a history of chronic arthritis and recurrent episodes of recumbency, increased serum gamma-glutamyl transferase, and complete inability to stand was submitted for necropsy. Gross changes included the presence of a white, firm, smooth, 6 cm × 4 cm × 3 cm mass that diffusely expanded and partially effaced the gall bladder and infiltrated the adjacent hepatic parenchyma. On cut surface, the mass was pale yellow and had small, irregular, dark yellow areas. Scattered through the pancreas were 2 gray, well-demarcated, soft, homogeneous, 1 cm in diameter nodules that bulged out from the capsular surface. The right femoral head had a locally extensive area of cartilage erosion. Histological and immunohistochemical evaluation of the gall bladder and pancreatic nodules revealed a primary cholecystic adenocarcinoma and multifocal insulinomas, respectively. A metastatic focus from the gall bladder neoplasm was observed infiltrating the right adrenal gland medulla. The goat also had mild pulmonary infestation by Muellerius capillaris. Primary hepatobiliary and pancreatic neoplasia is rare in goats, and to the authors' knowledge, neither cholecystic adenocarcinoma nor pancreatic insulinomas have been previously reported in this species., (© 2014 The Author(s).)

Tissue microarray (TMA) technology allows analysis of multiple tumour samples simultaneously on a single slide. The aim of the present study was to develop and assess a TMA containing 32 primary canine insulinomas and 13 insulinoma metastases. The results of histopathological and immunohistochemical analyses of triplicate core biopsies were compared with those of individual tissue sections using weighted κ statistics. Inter-observer agreement of TMA immunohistochemistry scores were assessed for chromogranin A (CgA), insulin, growth hormone (GH), growth hormone receptor (GHR) and Ki67 index, as well as the prognostic utility of clinicopathological, histopathological and immunohistochemical criteria. There was substantial agreement of scores for histopathological parameters (κ = 0.64-0.70) and a substantial to near-perfect agreement for homogenous immunohistochemical parameters (κ = 0.69-1.00). Except for GH, which demonstrated heterogeneous staining, there was good to excellent inter-observer agreement for all other immunohistochemical staining scores (intra-class correlation coefficients: 0.70-1.00). On univariate analysis, the presence of nuclear atypia was significantly predictive of disease-free intervals (DFIs) for canine insulinoma, while tumour size, TNM stage, necrosis and Ki67 index were significant in terms of prognosis, with respect to both DFI and survival time. On multivariate analysis, tumour size and Ki67 index retained predictive power for survival time, as did tumour size for DFI. This study confirms the applicability of TMA technology for evaluation of canine insulinoma., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

An 11-year-old male castrated mixed-breed dog was presented for exercise intolerance, tetraparesis, and persistent hypoglycemia. Abdominal ultrasound examination revealed 2 nodules within the right limb of the pancreas. Cytology from one nodule was consistent with a carcinoma of neuroendocrine origin, with a primary differential diagnosis of insulinoma. Histologic evaluation and immunohistochemistry for synaptophysin and insulin confirmed the diagnosis of insulinoma. Additionally, there was a solitary nodule of mineralized compact bone composing approximately 60% of the mass. To the authors' knowledge, this is the first report of osseous metaplasia within an insulinoma (islet cell carcinoma)., (© 2014 American Society for Veterinary Clinical Pathology and European Society for Veterinary Clinical Pathology.)

Canine pancreatic tumours are rare compared to human medicine and the detection and differentiation of pancreatic neoplasia is challenging with B-mode ultrasonography, which often leads to late clinical diagnosis and poor prognosis. This case report describes the findings of contrast-enhanced ultrasonography in four dogs with pancreatic adenocarcinoma or insulinoma. B-mode ultrasonography of the pancreas revealed a hypoechoic nodule in three dogs and heterogenous tissue in one dog. Contrast-enhanced ultrasonography was able to differentiate between two tumour types: adenocarcinomas showed hypoechoic and hypovascular lesions, whereas insulinomas showed uniformly hypervascular lesions. Contrast-enhanced ultrasonography findings were confirmed by cytology and/or histopathology. The results demonstrated that contrast-enhanced ultrasonography was able to establish different enhancement patterns between exocrine (adenocarcinoma) and endocrine (insulinoma) tumours in dogs.

The gene expression profile of 10 primary canine insulinomas was compared with that of their accompanying metastases using microarray analysis and quantitative real time-PCR. Analysis of microarray data revealed 84 genes that were differentially expressed between primary insulinomas and their metastases, along with 243 genes differentially expressed between a low-metastatic and a high-metastatic subset of primary insulinomas. The genes differently expressed between primary insulinomas and their metastases clustered together in nine signalling pathways. Comparing the low-metastatic to the high-metastatic subset of primary insulinomas, 26 pathways appeared to be significantly influenced. The acinar enzymes pancreatic lipase (PNLIP) and chymotrypsinogen B1 (CTRB1) were amongst the most down-regulated genes in the malignant group of primary insulinomas and in metastases. Immunofluorescence demonstrated co-localisation of insulin and PNLIP in tumour cells. Different subsets of canine insulinomas can be identified on the basis of their gene expression profile. Canine insulinomas appear to contain amphicrine cells, which exhibit both endocrine and exocrine cell features., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

This case report highlights an unusually prolonged, asymptomatic, disease-free interval in an aged male Labrador retriever that underwent partial pancreatectomy for a functionally active pancreatic insulinoma with histologically confirmed hepatic metastasis. The patient developed pancreatitis and nonseptic suppurative peritonitis 24 hr after surgical resection of the insulinoma and was managed medically until discharge. Three mo after surgery, the dog was diagnosed with exocrine pancreatic insufficiency (EPI) that was effectively managed with parenteral pancreatic enzymes. Due to normal glucose levels 3 mo postsurgically, liver samples from the initial surgery were resubmitted for immunohistochemistry. Results confirmed insulinoma metastasis with insulin expression. Ten mo postsurgically, the blood glucose was normal and serum insulin levels were slightly above the upper reference limit. The first hypoglycemic episode was documented 23 mo postoperatively, which was effectively managed with prednisone. The cause for the prolonged disease remission and survival was unknown, but was possibly a result of pancreatitis and peritonitis, partial spontaneous regression of metastatic lesions, or idiopathic. Despite life-threatening postoperative complications, this patient enjoyed a profoundly longer than expected survival. This case highlights the importance of removing the primary tumor (insulinoma) despite the presence of metastatic disease.

Background: Administration of streptozotocin (STZ) at a 21-day interval has been described in dogs with stage II and III insulinoma. Myelosuppression was not observed, suggesting the possibility of increasing dose intensity by decreasing the interval between doses., Objective: To describe the tolerability of a biweekly STZ protocol. A secondary objective was to describe the outcome of dogs treated with this protocol., Animals: Nineteen dogs with residual local, metastatic, or recurrent insulinoma., Methods: After surgery for insulinoma, or at the time of recurrence, dogs were treated with a previously described STZ and saline diuresis protocol. Treatments were administered every 14 days. All dogs received antiemetic treatment. Adverse events (AEs) were recorded and graded. Outcome endpoints assessed were progression-free survival (PFS) and survival., Results: None of the dogs experienced neutropenia or thrombocytopenia. Mild to moderate gastrointestinal toxicity was the most common AE. Diabetes mellitus was observed in 8 dogs and, in 6, resulted in euthanasia or death. Two dogs developed nephrotoxicity manifested as Fanconi syndrome in 1 and nephrogenic diabetes insipidus in the other. Six dogs developed increased alanine amino transferase activity. Hypoglycemia at the end of the STZ infusion, resulted in collapse in 1 dog and a generalized seizure in another. The median overall PFS and survival time were 196 and 308 days, respectively., Conclusions and Clinical Importance: Streptozotocin can be safely administered to dogs with insulinoma, but serious AEs are possible. Additional investigation is required to better define the role of STZ in managing dogs with insulinoma., (Copyright © 2013 by the American College of Veterinary Internal Medicine.)

Case Description: A 5-year-old male guinea pig (Cavia porcellus) was examined because of lethargy, weight loss, and episodic neurologic signs, including paddling in lateral recumbency, head tilt, and circling. Prior to initial examination, the animal was treated with corn syrup whenever it appeared lethargic, plus an unknown dosage of sulfadimethoxazole., Clinical Findings: The animal was thin, with abdominal distention and subtle torticollis. Chemistry panel results documented hypoglycemia (45 mg/dL). Corn syrup was discontinued in favor of a high-fiber formula fed via a syringe. Measurement of blood insulin concentration demonstrated hyperinsulinemia (> 1,440 pmol/L [> 201 μU/L]), with concurrent hypoglycemia (0.6 mmol/L [11 mg/dL])., Treatment and Outcome: Diazoxide treatment for presumptive insulinoma was started at a dosage of 5 mg/kg (2.3 mg/lb), p.o., every 12 hours. A blood glucose curve demonstrated persistent hypoglycemia, and the diazoxide dosage was gradually increased to 25 mg/kg (11.4 mg/lb), p.o., every 12 hours. A second glucose curve measurement 12 days later confirmed adequate euglycemic control. Three weeks after the initial diazoxide dosage increase, the animal was reexamined for constipation and abdominal distension and died the following day. Histologic analysis confirmed a pancreatic beta-cell tumor (insulinoma)., Clinical Relevance: To the authors' knowledge, this is the first report of premortem diagnosis and treatment of an insulinoma in a guinea pig. This case demonstrates that diazoxide treatment can help achieve euglycemia in hypoglycemic guinea pigs and is a potential treatment option for guinea pigs with insulinoma.

A 15-year old, neutered female, domestic shorthaired cat was presented for evaluation of a 3-month history of paroxysmal falling over and trembling. In laboratory work the cat displayed a mild hypoglycemia. Ultrasound revealed a nodule in the left pancreatic lobe and surgical excision was performed. The histological diagnosis was an insulinoma. To the authors knowledge this is the first ultrasound description of an insulinoma in a cat. Up to date the cat has a survival time of 32 months without recurrence of symptoms.

Case Description: A 9-year-old sexually intact male Staffordshire Bull Terrier and a 9-year-old neutered male Boxer were evaluated for intermittent neurologic signs including muscle tremors, ataxia, episodic collapse, disorientation, and seizures., Clinical Findings: Both dogs had low blood glucose and high serum insulin concentrations. Results of abdominal ultrasonography were unremarkable for both dogs. Exploratory laparotomy revealed a mass that extended from the body of the pancreas into the pancreaticoduodenal vein in each dog., Treatment and Outcome: Marginal resection of pancreatic masses was performed, and tumor thrombi were removed via venotomy in both dogs. Histologic evaluation indicated the masses were pancreatic islet cell tumors with tumor thrombi. Clinical signs resolved following surgical resection of tumors and tumor thrombi, and the dogs were euglycemic during the follow-up period (17 and 45 months after surgery)., Clinical Relevance: Although gross tumor thrombus formation has been identified in humans with insulinomas, tumor thrombi have not been previously reported for dogs with insulinomas. Surgical removal of tumor thrombi via venotomy seemed to be well tolerated by the dogs. Tumor thrombus formation did not seem to adversely affect prognosis for the 2 dogs of this report.

Insulinomas are rare malignant functional pancreatic tumors of the β cells that retain the ability to produce and secrete insulin. Insulinomas are the most common pancreatic neuroendocrine tumor in dogs that can induce a variety of clinical signs that result from hypoglycemia and secondary neuroglycopenic and adrenergic effects. Diagnosis and treatment is considered challenging, and the prognosis can be extremely variable depending on the therapeutic choices. This review aims to summarize and update classic knowledge with current trends in the diagnosis, treatment, and prognosis of insulinomas.

The long-term prognosis after surgical resection of canine insulinoma is poor. Signs of hypoglycaemia often recur soon after surgery because tumour tissue has only been resected partially and/or functional (micro-)metastases were present. Using quantitative real-time PCR, the expression of 16 target genes was compared between primary canine insulinomas and their corresponding metastases. There was significantly higher expression of genes encoding for growth hormone (GH) and insulin-like growth factor-1 (IGF-1) in metastases compared to their primary tumours. Immunohistochemical examination of proteins of the GH-IGF-1 axis revealed expression of GH, IGF-1 and GH receptor (GHR) in both primary insulinomas and metastases. Immunohistochemical staining for IGF-1 was significantly higher in metastases compared to primary tumours., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Metabolic complications of endocrine surgery occur commonly and precautions should be taken to avoid potentially life-threatening situations and to lessen expense associated with a more extended hospital stay. Common complications of endocrine surgery as well as prevention strategies will be reviewed for pancreatic, parathyroid, and adrenal surgery.

A 5.5-y-old spayed female ferret (Mustela putorius furo) with a history of adrenal disease, respiratory disease, and chronic obesity was evaluated for progressive lethargy and ataxia, diminished appetite, and possible polyuria and polydipsia. Physical examination revealed obesity, lethargy, tachypnea, dyspnea, a pendulous abdomen, significant weakness and ataxia of the hindlimbs, prolonged skin tenting, and mild tail-tip alopecia. Clinicopathologic analysis revealed severe hyperglycemia, azotemia, an increased anion gap, glucosuria, ketonuria, proteinuria, and hematuria. Abdominal ultrasonography showed hyperechoic hepatomegaly, bilateral adrenomegaly, splenic nodules, mild peritoneal effusion, and thickened and mildly hypoechoic limbs of the pancreas with surrounding hyperechoic mesentery. Fine-needle aspirates of the liver were highly suggestive of hepatic lipidosis. In light of a diagnosis of concurrent diabetic ketoacidosis and pancreatitis, the ferret was treated with fluid therapy, regular and long-acting insulin administration, and pain medication. However, electrolyte derangements, metabolic acidosis, dyspnea, and the clinical appearance of the ferret progressively worsened despite treatment, and euthanasia was elected. Necropsy revealed severe hepatic lipidosis, severe suppurative pancreatitis and vacuolar degeneration of pancreatic islet cells, a pancreatic β islet cell tumor, bilateral adrenal cortical adenomas, and myocardial fibrosis. To our knowledge, this case represents the first report of concurrent diabetes mellitus, pancreatitis, pancreatic β islet cell tumor (insulinoma), and adrenal disease in a domestic ferret. The simultaneous existence of 3 endocrine diseases, pancreatitis, and their associated complications is a unique and clinically challenging situation., (Copyright 2011 by the American Association for Laboratory Animal Science)

Background: Measurement of canine serum insulin has relied on methods developed to measure human insulin. A species-optimized test for measurement of serum insulin in dogs is now commercially available., Objective: The purpose of this study was to validate the canine ELISA for determination of serum insulin concentration in dogs., Methods: Precision was determined by evaluating intra- and interassay coefficient of variation (CV), and accuracy was determined by dilution and spike recovery studies. A method comparison study with samples from 34 clinically healthy dogs and 73 dogs examined for various illnesses and disorders ("patients") was performed using the canine ELISA and an ELISA for human insulin. Biologic relevance of the canine assay was evaluated by measuring insulin in samples collected from 8 healthy dogs after administration of glucagon. A stability study was preformed with 6 samples stored at 20°C, 4-8°C, and -20°C., Results: For the canine ELISA, intra- and interassay CVs were 4.3-7.8% and 4.4-7.7%, respectively. Mean recovery after dilution was 99% and recovery after spiking with porcine insulin was 116%. The canine and human ELISAs correlated well (r(2) =.94 for healthy dogs, r(2) =.88 for patient samples). After glucagon injection serum insulin concentrations increased significantly in 8 dogs. Insulin was stable for 30 days in 6 serum samples stored at -20°C and in most samples for 8 days at 4-8°C. Insulin was stable for <3 days at room temperature (20°C)., Conclusions: The new canine serum insulin ELISA had good precision and accuracy and correlated well with the previously used assay., (©2011 American Society for Veterinary Clinical Pathology.)

Objectives: To describe partial pancreatectomy using a bipolar vessel-sealing device (BVSD) and compare this novel technique to the conventional suture-fracture (SF) method for canine insulinoma., Methods: Pre-, intra- and postoperative data of eight dogs with insulinoma, which underwent resection using the BVSD (LigaSure V), were prospectively collected and compared with those of eight randomly selected case-matched patients that underwent resection using the conventional SF technique., Results: Mean surgical time was significantly (P=0·022) shorter in the BVSD (107 ± 9 minutes) than in the SF (135 ± 22 minutes) group. The BVSD technique was negatively associated with surgical time and duration of the hospitalisation period. Neither technique caused intraoperative complications, such as bleeding, collateral damage to adjacent tissues or problems with sealing or suturing the pancreatic tissue. Three dogs in the SF group and none in the BVSD group developed postoperative clinical signs associated with pancreatitis., Clinical Significance: BVSD is a safe and viable alternative to conventional methods of pancreatectomy for canine insulinoma. It provides the possibility to remove insulinomas in the pancreatic limbs and corpus with relative ease. BVSD pancreatectomy in dogs with insulinoma significantly decreases operative and hospitalisation times and is not associated with more clinical complications than SF pancreatectomy., (© 2011 British Small Animal Veterinary Association.)

Pancreatic islet cell adenoma, oral squamous cell carcinoma, peripheral polyneuropathy, and multiple age-associated degenerative lesions were diagnosed in an aged Sprague-Dawley rat presenting with polyuria, polydypsia, dehydration, anorexia, weight loss, and posterior weakness. Microscopically, the islet cell adenoma was encapsulated by fibrous tissue and composed of packets of oval-to-polygonal monomorphic cells in a fibrovascular stroma. Immunohistochemically, the majority of cells within the mass expressed insulin. In light of the histologic and immunohistochemical findings, a diagnosis of insulinoma was made. The oral squamous cell carcinoma, grossly presenting as gingival ulceration, was composed of nests and cords of squamous epithelial cells that focally eroded and infiltrated the hard palate and resulted in degeneration of the maxillary nerve. The peripheral polyneuropathic lesions were characterized by extensive axonal degeneration and microangiopathic changes that were highly suggestive of a hypoglycemic etiopathogenesis secondary to insulinoma.