Pancreatitis, panniculitis, and polyarthritis syndrome in a dog with hyalinizing pancreatic adenocarcinoma

A 10-y-old spayed female Cavalier King Charles Spaniel dog was presented to the Veterinary Teaching Hospital because of recurrent chronic abscesses on the distal pelvic limbs, fever, lethargy, lameness of unknown etiology, and chronic pancreatitis. Sterile nodular panniculitis was diagnosed after an extensive workup, and the dog initially responded to immunosuppressive therapy, but relapse and spread of cutaneous lesions and acute lameness occurred after 11 mo, and euthanasia was elected. Postmortem examination confirmed hyalinizing pancreatic adenocarcinoma with pancreatitis, panniculitis, polyarthritis (PPP), and osteomyelitis. Histopathology and bacterial and fungal cultures were supportive of a sterile process, specifically the PPP syndrome, which is a rare, potentially life-threatening, systemic manifestation of pancreatic disease in both people and animals. To our knowledge, a clinicopathologic description of a hyalinizing pancreatic adenocarcinoma associated with this rare syndrome has not been reported previously in a dog.