Imaging findings in pancreatic neoplasia and nodular hyperplasia in 19 cats

Pancreatic neoplasia in cats is rare and associated with a poor prognosis, but pancreatic nodular hyperplasia is a common incidental finding. The purpose of this study was to describe radiographic and ultrasonographic findings in cats with pancreatic neoplasia or nodular hyperplasia. Fourteen cats (age 3-18 years) were diagnosed with malignant pancreatic tumors: carcinoma/adenocarcinoma (n = 11), lymphoma (n = 1), squamous cell carcinoma (n = 1), and lymphangiosarcoma (n = 1). The most common radiographic findings were an abdominal mass or mass effect (6/6) and lack of serosal margin detail (4/6). On ultrasound, the most common finding was a focal pancreatic mass or nodule, with a size range from 0.4 cm to more than 7.0 cm (8/14). Lymphadenopathy (7/14) and abdominal effusion (7/14) were frequently seen. Five cats (age 10-16 years) with adenomatous/nodular hyperplasia had an abdominal mass or mass effect as the most common radiographic finding (3/3). On ultrasound, all cats had multiple hypoechoic nodules between 0.3 and 1.0 cm associated with the pancreas. Other common findings were pancreatic thickening (2/5), lymphadenopathy (2/5), and abdominal effusion (2/5). The only imaging finding unique to malignant pancreatic tumors was the presence of a single pancreatic nodule or mass exceeding 2cm in at least one dimension (4/14). Although there was a tendency for neoplastic lesions to manifest as single larger lesions and for nodular hyperplasia to manifest as multiple smaller lesions, there was overlap of the imaging findings in both entities. Radiographs and ultrasound can complement but not replace cytology and histopathology in the diagnosis of feline pancreatic neoplasia.