Malignant Metastatic Insulinoma in a Dog

Authors

  • Ozlem Ozmen Department of Pathology, Faculty of Veterinary Medicine, Mehmet Akif Ersoy University, Burdur, Turkey.
  • Yusuf Sinan Sirin Department of Surgery, Faculty of Veterinary Medicine, Mehmet Akif Ersoy University, Burdur, Turkey.

DOI:

https://doi.org/10.22456/1679-9216.82584

Abstract

Background: Insulinomas are tumors of the pancreatic islet beta cells that secreting insulin. They are malignant neoplasms and rarely seen in dogs. Because insulinomas secrete excessive insulin and hypoglycemia occur. The most common clinical symptoms are seizures, extreme weakness, and other neurological abnormalities. The tumors typically release insulin episodically, with clinical signs being seen intermittently as a result. These are most often associated with prolonged starvation or prolonged periods of exertion. Insulinoma occurs most often in middle-aged and older dogs, averaging nine years in age. They affect both sexes and are more likely in larger breeds. The most commonly afflicted breeds are German Shepherds, Irish Setters, Boxers, Golden Retrievers and Terriers.
Case: In this study, a case of malignant insulinoma with multiorgan metastasis in a 7-year-old hunting dog that brought to the clinic with complaints of constipation and inappetence were evaluated by clinical, cytological, histopathological and immunohistochemical fndings. Owner stated that the animal suffers from constipation for 4 days, but no vomitus or nervous symptoms were present. Clinical efforts not solved the constipation. For to the defnitive diagnosis the dog decided to underwent laparotomy. After a midline abdominal approach multiple whitish, hard and irregular metastatic tumoral masses were observed in different abdominal organs. Because of the poor prognosis and according to owner’s acceptance the dog euthanatized at the same time. At necropsy, a bloody serous fluid approximately 500 mL was found in the abdominal cavity. The intestines were hyperemic and hemorrhagic in some areas. A hemorrhagic 9x5x3 cm in diameter mass was observed on the pancreas. Mesenterial adhesions were formed due to mass between duodenum and jejunum. The mass was moderately hard and cut surface was bloody, necrosis was observed in some areas. At the gross examination, whitish color, various sized and multiple metastatic masses were noted in spleen, liver, lymph nodes and lungs. Before formalin fxation, impression smears were made from the pancreatic mass. In cytological preparations of the lesion, epithelial cells in different shapes and sizes were observed. At the histopathological examination, the tumor mass consisted of anaplastic, pleomorphic cells that have pale cytoplasm, vesicular nucleus and prominent nucleolus. Diffuse necrotic areas were noted in the mass. Similar metastatic masses were seen in liver, spleen, lungs and kidneys. The tumor cells were positive for insulin and negative for glucagon immunohistochemically.
Discussion: Insulinomas generally caused nervous symptoms due to hypoglycemia. Metastasis may occur in some cases and generally lymph node metastasis occurs. Spleen metastasis are very rare in insulinoma cases. The mean age of the occurrence of insulinoma is generally older than 9-year-old. In this case, a case of malignant insulinoma with multiorgan metastasis and caused constipation due to intestinal adhesions in a dog was presented with clinical and pathological fndings. Best of the author’s knowledge insulinoma as a cause of constipation not previously reported in a dog. The aim of this study was to report a case of metastatic insulinoma without neurological symptoms but constipation in a 7 years old hunting dog by clinical, pathological, cytological and immunohistochemical fndings.


Keywords: Malignant insulinoma, constipation, cytology, histopathology, immunohistochemistry, dog.

Downloads

Download data is not yet available.

References

Capen C.C. 2007. Insulinoma. In: Maxie M.G. (Ed). Jubb, Kennedy and Palmer’s Pathology of Domestic Animals. 5th edn. v.2. Philadelphia: Saunders Elsevier, pp.421-423.

Chang S.C., Liao J.W., Lin Y.C., Liu C.I. & Wong M.L. 2007. Pancreatic acinar cell carcinoma with intracranial metastasis in a dog. Journal of Veterinary Medical Science. 69(1): 91-93.

Cordner A.P., Sharkey L.C., Armstrong P.J. & Mcateer K.D. 2015. Cytologic fndings and diagnostic yield in 92 dogs undergoing fne-needle aspiration of the pancreas. Journal of Veterinary Diagnostic Investigation. 27(2): 236-240.

Cullen J.M. & Popp J.A. 2002. Tumors of the exocrine pancreas. In: Meuten D.J. (Ed). Tumors in Domestic Animals. 4th edn. Ames: Iowa State University Press, pp.478-481.

Dennis M.M., O’Brien T.D., Wayne T., Kiupel M., Williams M. & Powers B.E. 2008. Hyalinizing pancreatic adenocarcinoma in six dogs. Veterinary Pathology. 45: 475-483.

Goutal C.M., Brugmann B.L. & Ryan K.A. 2012. Insulinoma in dogs: a review. Journal of American Animal Hospital Association. 48: 151-163.

Hess R.S. 2010. Insulin-Secreting Islet Cell Neoplasia. In: Ettinger S.J. & Feldman E.C. (Eds). Textbook of Veterinary Internal Medicine. 7th edn. Philadelphia: W.B. Saunders, pp.1779-1782.

Koenig A. 2009. Hypoglycemia. In: Silverstein D.C. & Hopper K. (Eds). Small Animal Critical Care Medicine. Philadelphia: W.B. Saunders, pp.295-299.

Kruth S.A., Feldman E.C. & Kennedy P.C. 1982. Insulin-secreting islet cell tumors: establishing a diagnosis and the clinical course for 25 dogs. Journal of American Veterinary Medical Association. 181: 54-58.

Leifer C.E., Peterson M.E. & Matus R.E. 1986. Insulin-secreting tumor: diagnosis and medical and surgical treatment in 55 dogs. Journal of American Veterinary Medical Association. 188: 60-64.

Morris J. & Dobson J. 2001. Gastro-intestinal Tract. In: Morris J. & Dobson J. (Eds). Small Animal Oncology. Oxford: Blackwell Science Ltd., pp.125-143.

Nelson R.W. & Couto C.G. 1998. Insulinoma. In: Nelson R.W. & Couto C.G. (Eds.). Small Animal Internal Medicine. 2nd edn. Missouri: Mosby Inc., pp.734-774.

Oskoui-Zadeh K., Jamshidi S.H., Ashrafhelan J. & Veshkini A. 2008. Exocrine pancreatic adenocarcinoma in a toy breed dog. Iranian Journal of Veterinary Research Shiraz University. 9(1): 87-91.

Polton G.A., White R.N., Brearley M.J. & Eastwood J.M. 2007. Improved survival in a retrospective cohort of 28 dogs with insulinoma. Journal of Small Animal Practice. 48: 151-156.

Tobin R.L., Nelson R.W., Lucroy M.D., Woolridge J.D. & Feldman E.C. 1999. Outcome of surgical versus medical treatment of dogs with beta cell neoplasia: 39 cases (1990-1997). Journal of American Veterinary Medical Association. 215: 226-230.

Trifonidou M.A., Kirpenstiin J. & Robben J.H. 1998. A retrospective evaluation of 51 dogs with insulinoma. Veterinary Quarterly. 20: 114-115.

Van Ham L., Braund K.G., Roels S. & Putcuyps I. 1997. Treatment of a dog with an insulinoma-related peripheral polyneuropathy with corticosteroids. Veterinary Record. 141: 98-100.

Published

2016-01-01

How to Cite

Ozmen, O., & Sirin, Y. S. (2016). Malignant Metastatic Insulinoma in a Dog. Acta Scientiae Veterinariae, 44(1), 5. https://doi.org/10.22456/1679-9216.82584

Issue

Section

Case Report