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Exocrine Pancreatic Neoplasia - Dogs and Cats (view source)
Revision as of 20:45, 25 June 2016
, 20:45, 25 June 2016no edit summary
==Introduction==
Primary pancreatic tumours are rare (accounting for less than 0.5% of all cancers in the dog), however the pancreas is also a site for metastasis from particularly gastro-intestinal neoplasms. Primary tumours include:
* [[Carcinoma#Pancreatic|Carcinomas]]
* Adenocarcinomas
* [[Adenoma#Pancreatic|Adenomas]]
It is important to make the distinction between pancreatic neoplasia and [[Pancreatic Nodular Hyperplasia|pancreatic nodular hyperplasia]] which frequently occurs in older dogs and cats and is non-significant.
Description (aetiology, pathogenesis etc)
Diagnosis (based on typical history, clinical signs, physical exam findings, imaging/laboratory results)
==Signalment==
[[Carcinoma#Pancreatic|Carcinomas]]:
* Usually female dogs with a mean age of 10 years
* Spaniels and Airedale terriers may have breed predispositions
<gallery>
Image:Cocker_spaniel.jpg|'''English Cocker Spaniel'''<p> Ellen Levy Finch (2004) WikiMedia Commons
Image:Airedale_Terrier.jpg|'''Airedale Terrier'''<p> Pleple2000 (2006) WikiMedia Commons
</gallery>
* Affected cats have a mean age of 12 years
==Description==
Aetiology is idiopathic. [[Adenoma#Pancreatic|Adenomas]], although they do not metastasise and are frequently small and focal, can compress the surrounding pancreas. [[Carcinoma#Pancreatic|Carcinomas]] are aggressive with local invasion of the stomach or duodenum and metastasis to the liver, regional lymph nodes (hepatic and splenic), lungs, periotoneal surface and other abdominal organs usually occurring prior to a diagnosis being reached. Other complications include blockage of the common bile duct and [[Exocrine Pancreatic Insufficiency|exocrine pancreatic insufficiency]]. [[Pancreatitis|Pancreatitis]] can also occur where pancreatic atrophy results in tumour necrosis and an inflammatory response.
==Diagnosis==
===Clinical Signs===
Non-specific including:
* Lethargy
* Weight loss - marked in cats
* Anorexia - marked in cats
* Vomiting
* Diarrhoea
* Constipation
* Abdominal pain/distension due to mass effect or abdominal effusions
* Jaundice - if biliary obstruction
* Alopecia - as a paraneoplastic syndrome, occurring ventrally, facially and on the limbs in cats with adenocarcinoma
Such signs may also occur with concurrent [[Pancreatitis|pancreatitis]]. Alternatively clinical signs may reflect those of metastatic disease.
===Physical Examination===
In cats, an abdominal mass may be palpable.
===Haematology and Biochemistry===
Potential abnormalities include:
* Mild anaemia
* Neutrophilia
* Elevated hepatic enzymes or bilirubinaemia - if there is cholestasis or biliary obstruction
* Hyperglycaemia - If there is concurrent beta cell destruction
* Hypokalaemia
===Plain and Contrast Radiography===
Plain abdominal radiography may reveal a mass or mottled appearance on account of local peritonitis. In addition, there may be diplacement of the descending duodenum and pylorus. Where there is peritoneal metastasis and effusion loss of serosal detail and increased radiodensity may be observed. Thoracic radiography is also advised for pulmonary metastases.
Positive contrast radiography can be used to evaluate gastric emptying which can be delayed with pancreatic neoplasia. Compression or invasion of the duodenum may also be seen.
===Ultrasonography===
Provides information on the extent of the tumour and its invasiveness. A guided fine needle aspirate may be taken at this time, however, cytological examination is often unrewarding as pancreatic tumour cells do not exfoliate well.
===Exploratory Celiotomy===
Excising the whole tumour if operable or taking a sample via shave biopsy or crush ligation allows histopathological confirmation.
==Treatment==
===Surgery===
Usually at the time of diagnosis adenocarcinomas have already metastasised or local invasion has already taken place. If metastasis has no yet occurred surgical resection may be attempted with care to avoid iatrogenic trauma to the vascular supply to the proximal duodenum and obstruction of the main pancreatic duct. Total pancreatectomy and pancreaticoduodenectomy (Whipple's procedure) are not advised. Tumours of the body or base of the pancreas are inoperable. Gastrojejunostomy (gastrointestinal bypass) may be performed for short term palliation. Small pancreatic adenomas may be removed via partial pancreatectomy.
===Chemotherapy===
Not recommended.
===Radiotherapy===
Not recommended.
==Prognosis==
Poor for adenocarcinomas on account of their invasiveness and early metastasis. Survival time is less than 1 year for such tumours regardless of treatment.
{{Learning
|Vetstream = [https://www.vetstream.com/canis/Content/Disease/dis01111.asp Pancreas: neoplasia of the exocrine pancreas (adenocarcinoma)]
}}
==References==
* Morris J, Dobson J (2001) Gastrointestinal Tract, in Small Animal Oncology, Blackwell Science, pp 140-142
* Liptak J. M, Withrow S.J, (2007), Cancer of the Gastrointestinal Tract, in Withrow and MacEwen's Small Animal Clinical Oncology, fourth edition, Eds Withrow S.J, Vail D.M, Missouri, Saunders Elsevier, pp 479-480
[[Category:Pancreas_-_Hyperplastic_and_Neoplastic_Pathology]][[Category:Pancreatic Diseases - Dog]][[Category:Pancreatic Diseases - Cat]]
[[Category:To_Do_-_Clinical]]
[[Category:Neoplasia]]