Difference between revisions of "Exocrine Pancreatic Neoplasia - Dogs and Cats"
Michuang0720 (talk | contribs) |
|||
| (22 intermediate revisions by 5 users not shown) | |||
| Line 1: | Line 1: | ||
| − | + | {{Unfinished}} | |
| + | |||
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: | 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: | ||
| − | * | + | * Carcinomas |
* Adenocarcinomas | * Adenocarcinomas | ||
| − | * | + | * Adenomas |
| + | |||
| + | It is important to make the distinction between pancreatic neoplasia and pancreatic nodular hyperplasia which frequently occurs in older dogs and cats and is non-significant. | ||
| − | |||
==Signalment== | ==Signalment== | ||
| − | + | Carcinomas: | |
* Usually female dogs with a mean age of 10 years | * Usually female dogs with a mean age of 10 years | ||
* Spaniels and Airedale terriers may have breed predispositions | * Spaniels and Airedale terriers may have breed predispositions | ||
| + | * Affected cats have a mean age of 12 years | ||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
| − | |||
==Description== | ==Description== | ||
| − | Aetiology is idiopathic. | + | Aetiology is idiopathic. Adenomas, although they do not metastasise and are frequently small and focal they can compress the surrounding pancreas. 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 occurring prior to a diagnosis being reached. Other complications include blockage of the common bile duct and exocrine pancreatic insufficiency. Pancreatitis can also occur where pancreatic atrophy results in tumour necrosis and an inflammatory response. |
| Line 32: | Line 29: | ||
* Diarrhoea | * Diarrhoea | ||
* Constipation | * Constipation | ||
| − | * Abdominal pain/distension due | + | * Abdominal pain/distension due mass effect or abdominal effusions |
* Jaundice - if biliary obstruction | * Jaundice - if biliary obstruction | ||
| − | * Alopecia - as a paraneoplastic syndrome, | + | * Alopecia - as a paraneoplastic syndrome, ventral, facial and limbs in cats with adenocarcinoma |
| − | Such signs may also occur with concurrent | + | Such signs may also occur with concurrent pancreatitis. Alternatively clinical signs may reflect those of metastatic disease. |
===Physical Examination=== | ===Physical Examination=== | ||
| − | In cats, | + | In cats, a mass may be palpable in the abdomen |
===Haematology and Biochemistry=== | ===Haematology and Biochemistry=== | ||
| Line 62: | Line 59: | ||
==Treatment== | ==Treatment== | ||
===Surgery=== | ===Surgery=== | ||
| − | + | Often 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 erm palliation. Small pancreatic adenomas may be removed via partial pancreatectomy. | |
===Chemotherapy=== | ===Chemotherapy=== | ||
| Line 72: | Line 69: | ||
==Prognosis== | ==Prognosis== | ||
| − | Poor for adenocarcinomas on account of their invasiveness and early metastasis. Survival time is less than 1 year for such tumours | + | Poor for adenocarcinomas on account of their invasiveness and early metastasis. Survival time is less than 1 year for such tumours. |
| − | |||
| − | |||
| − | |||
==References== | ==References== | ||
* Morris J, Dobson J (2001) Gastrointestinal Tract, in Small Animal Oncology, Blackwell Science, pp 140-142 | * Morris J, Dobson J (2001) Gastrointestinal Tract, in Small Animal Oncology, Blackwell Science, pp 140-142 | ||
| − | * | + | * Withrow S.J, Vail D.M (2007), Cancer of the Gastrointestinal Tract, in Withrow and MacEwen's Small Animal Clinical Oncology, fourth edition, Missouri, Saunders Elsevier, pp 479-480 |
| − | |||
| − | |||
| − | |||
Revision as of 15:57, 12 August 2009
 |
This article is still under construction. |
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:
- Carcinomas
- Adenocarcinomas
- Adenomas
It is important to make the distinction between pancreatic neoplasia and pancreatic nodular hyperplasia which frequently occurs in older dogs and cats and is non-significant.
Signalment
Carcinomas:
- Usually female dogs with a mean age of 10 years
- Spaniels and Airedale terriers may have breed predispositions
- Affected cats have a mean age of 12 years
Description
Aetiology is idiopathic. Adenomas, although they do not metastasise and are frequently small and focal they can compress the surrounding pancreas. 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 occurring prior to a diagnosis being reached. Other complications include blockage of the common bile duct and exocrine pancreatic insufficiency. 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 mass effect or abdominal effusions
- Jaundice - if biliary obstruction
- Alopecia - as a paraneoplastic syndrome, ventral, facial and limbs in cats with adenocarcinoma
Such signs may also occur with concurrent pancreatitis. Alternatively clinical signs may reflect those of metastatic disease.
Physical Examination
In cats, a mass may be palpable in the abdomen
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
Often 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 erm 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.
References
- Morris J, Dobson J (2001) Gastrointestinal Tract, in Small Animal Oncology, Blackwell Science, pp 140-142
- Withrow S.J, Vail D.M (2007), Cancer of the Gastrointestinal Tract, in Withrow and MacEwen's Small Animal Clinical Oncology, fourth edition, Missouri, Saunders Elsevier, pp 479-480