Pericolonic mass containing chyle as a presumed sequela to chronic pancreatitis in a dog

A 9-year-old dog was admitted because of recurrent episodes of chronic pancreatitis. Ultrasonography revealed a multiloculated, fluid-filled cystic mass at the caudal portion of the stomach. Guided fine-needle aspirates yielded a fluid consistent with chyle. The dog underwent surgery during which a 6- to 8-cm mass was found adhered to the mesocolon and serosa of the transverse colon. Intraoperative lymphangiography revealed lymphangiectasia, but contrast medium did not accumulate within the mass. The mass and a portion of transverse colon were removed en bloc. Results of histologic examination were consistent with an abscess. Pancreatic enzymatic digestion may allow abscesses to extend beyond pancreatic parenchyma, cause severe local inflammation, and encapsulate and incorporate adjacent abdominal lymphatics. Subsequent lymphatic leakage can result in chyle within the abscess. Inflammatory masses of the pancreas are a rare, but serious, complication of pancreatitis in dogs. Familiarity with these types of lesions can aid in selection of appropriate treatments.