C.M. Borschensky¹, K. Steiger², A. Staudacher³, M. Schlitter², I. Esposito², H. Aupperle¹
¹Laboklin GmbH&Co. KG, Bad kissingen, Germany
²TU München, Institute of Pathology, München, Germany
³Veterinary Clinic Dr. Staudacher, Aachen, Germany
Pancreatic neoplasms in the cat mostly exhibit a solid growth pattern and are diagnosed as carcinomas. In contrast, only few reports about cystic pancreatic lesions exist. Until now, only benign cystic pancreatic lesions are described in the literature. According to the histological pattern, they have been termed as cysts, (acinar) cystadenoma or pseudocysts. In man, cystic pancreatic neoplasms are classified according to the localisation (intra-/extraductal), growth pattern and differentiation (mucinous, (tubulo)papillary, serous, acinar).
The aim of this study was to characterise feline pancreatic neoplasms in more detail, based on the human classification system with a special view on cystic lesions.
Pancreatic masses sent to LABOKLIN from 19 domestic cats (7-14 years) were investigated routinely macroscopically and by histological methods (H.&E. stain).
The neoplasms showed a cystic (n=8) or solid (n=11) pattern. Cystic pancreatic tumors were up to 7 cm in diameter and were classified as benign variants in five and malignant variants in three cases. Based on the human classification system, they were classified as tubulopapillary (n=2), acinar (n=2) and mixed (n=1) adenomas and mixed carcinomas (n=3), respectively.
Solid pancreatic nodules were diagnosed as carcinomas with a tubular (n=5) or acinar (n=6) differentiation pattern.
In summary, the gross structure (solid versus cystic) seems to be of prognostic relevance. In contrast to solid tumors, cystic pancreatic lesions in the cat behave benign in a higher percentage of cases, resulting in a better prognosis. Therefore, surgical excision of these cystic masses can be recommended. With respect to the human classification system, three different subtypes of cystic pancreatic neoplasms were detected in the cat that have not been described before in veterinary medicine: tubulopapillary, acinar and mixed. To best of our knowledge, this is the first report of cystic adenocarcinomas in feline pancreas.
Further corresponding clinical and histological investigations are needed for a better diagnostic (ultrasound, MRI) and prognostic characterisation of cystic lesions in feline pancreas.
Conflicts of interest: No conflicts of interest reported