Pancreatic Tumors

+ Biologic Behavior

Pancreatic ADC is a tumor of the exocrine pancreas originating in either the acinar cells or ductular epithelium
Very rare in cats and rare in dogs accounting for < 0.05% of all cancers
75% of feline pancreatic carcinomas are diffuse
75% of pancreatic carcinomas in humans are located in the head of the pancreas with invasion of the duodenum, stomach, and bile duct common
N-ethyl-N'-nitro-N-nitrosoguanidine induces pancreatic ADC in dogs with intraductal administration
Exocrine pancreatic carcinoma has been diagnosed concurrently with diabetes mellitus and hyperadrenocorticism in 3 cats and diabetes mellitus in 22% (8/37) cats suggesting a possible association between these disease
Metastasis to regional lymph nodes and distant sites is frequent with 50%-78% metastatic rate at diagnosis
Metastatic sites: liver, small intestine, and lungs in cats and dogs, and mesenteric lymph nodes, mesentery ± skull and vertebrae in dogs

Clinical signs are non-specific and include vomiting, anorexia, weakness, weight loss, maldigestion, exocrine pancreatic insufficient, icterus with obstruction of the common bile duct ± abdominal effusion secondary to peritoneal metastasis, carcinomatosis, or compression of the caudal vena cava
Clinical signs are similar to pancreatitis

Blood test abnormalities are non-specific and include mild anemia, neutrophilia, and bilirubinemia
Serum amylase and lipase are inconsistently elevated
Barium studies may reveal slow intestinal transit time or invasion or compression of the duodenum
Pancreatic mass detected with either survey radiographs or abdominal ultrasonography in 50% cases
Ultrasound-guided aspirate cytology sensitive with correct diagnosis in 92%
DDx: pancreatic nodular hyperplasia and pancreatic pseudocyst

Treatment is complicated by frequent and extensive local invasiveness and metastasis

Surgical techniques: complete pancreatectomy or pancreaticoduodenectomy (Whipple's procedure)
High morbidity and mortality (5%-30% in humans) without significant improvement in survival
Palliative surgical techniques include duodenal by-pass (i.e., gastrojejunostomy) and biliary diversion

Unknown effect in animals and limited value in humans with pancreatic ADC
Taxols and gemcitabine have been used with some improvement in survival time in humans