Pancreatic pseudocyst associated with chronic-active necrotizing pancreatitis in a cat.

A 13-year-old, neutered female domestic shorthair was referred for evaluation of chronic, intermittent vomiting of approximately two years' duration. On physical examination, a fluctuant mass was palpated in the left cranial abdominal quadrant. Significant laboratory findings included neutrophilia, hyperglycemia, hyperlipasemia, and proteinuria. A distinct mass within the left cranial quadrant was noted on abdominal radiographs. Ultrasonographically, the pancreas appeared slightly hyperechoic with a hypoechoic mass arising from its left lobe. A cystic mass in the left lobe of the pancreas was identified during an exploratory celiotomy. The mass and affected areas of the pancreas and a portion of the spleen were resected. The cat recovered completely. Cytological, histological, and laboratory evaluations of the mass were consistent with pancreatic pseudocyst formation, which has been reported in dogs and humans but has not yet been reported in cats.