Suspected pancreatic carcinoma needle tract seeding in a cat.

CASE SUMMARY: A 15-year-old male neutered domestic longhair cat was referred for investigation of a pancreatic nodule. Fine-needle aspiration of the nodule was performed on two occasions, 2 weeks apart, and cytology revealed pyogranulomatous inflammation and moderately dysplastic exocrine pancreatic epithelium, suspicious for neoplasia. Thoracic radiographs were unremarkable and a partial pancreatectomy was performed. On histopathology, the nodule was diagnosed as a moderately differentiated pancreatic adenocarcinoma. Two weeks after surgery, a firm subcutaneous nodule was detected on the left ventrolateral abdomen. Cytology of the nodule was suggestive of pancreatic carcinoma and needle tract seeding was suspected. With palliative treatment, the cat lived a further 136 days. RELEVANCE AND NOVEL INFORMATION: To our knowledge, this represents the first report of suspected transabdominal needle tract seeding of pancreatic carcinoma following fine-needle aspiration in veterinary medicine. Veterinarians should consider this when discussing risks of pancreatic fine-needle aspiration with owners and should attempt to minimise the number of needle aspirations where possible.

Changes in duodenal CD163-positive cells in dogs with chronic enteropathy after successful treatment.

Chronic enteropathy (CE) in dogs is characterized retrospectively per treatment response as food-responsive enteropathy (FRE), antibiotic-responsive enteropathy (ARE), and immunosuppressant-responsive enteropathy (IRE) - the latter most resembling inflammatory bowel disease in people. The aim of this study was to characterize duodenal macrophages (Mϕ) in CE using immunohistochemistry; with calprotectin (CAL) as a marker of early differentiated Mϕ and CD163 expression as a marker for resident Mϕ in the duodenum before and after treatment. Prior to treatment, dogs with FRE and IRE had a lower CD163+/CAL+ ratio than control dogs (CTRL) in crypts; this increased significantly and normalized compared with CTRL after treatment. Conversely, the CD163+/CAL+ ratio in dogs with ARE was comparable to that in healthy dogs before and after treatment. In summary, these results suggest that Mϕ play a role in the pathogenesis of CE in FRE and IRE, with a decrease in resident Mϕ and an increase in early differentiated Mϕ, but not in ARE dogs. Mϕ normalize after successful treatment.