October's Case of the Month

Pancreatic Mass in a Cat

Dr. Anne Desrochers

Patient Information:

Age: 3-year old
Gender: Neutered Male
Species: Feline
Breed: Bengal

History and clinical findings:

The patient presented for inappetence, weight loss, soft yellow feces and changes in behavior. Mild abdominal discomfort was noted on palpation. Bloodwork revealed fPL of 7.5 (normal <3.5). Abdominal ultrasound was recommended.

Ultrasound Interpretation:

A well-defined heterogenous hyperechoic echogenicity mass contained a few pin-point hyperechoic areas of mineralization was seen in the right cranial abdominal region. The mass was adjacent to the descending part of the duodenum and appeared to be involving the proximal portion of the right pancreatic limb, causing mild pancreatic duct dilation. The mass measured 1.7x1.9cm in diameter and vascular signal was obtained when assessing the lesion with color flow Doppler.

Ultrasound Images

Image 1: Longitudinal view of the mass showing its proximity to the duodenum and association with the right limb of the pancreas using a high frequency linear transducer.

Image 2: Longitudinal view of the mass and adjacent anatomic structures obtained with a high frequency linear transducer.

Sampling:

Ultrasound-guided fine-needle biopsies of the mass were collected under sedation and submitted for cytological analysis.Fine-needle biopsies of the pancreas mass and spleen were collected and submitted Fine-needle biopsies of the pancreas mass and spleen were collected and submitted Fine-needle biopsies of the pancreas mass and spleen were collected and submitted

Diagnosis:

A non-lymphoid malignancy was suspected with high confidence (100% certainty). The cells were anaplastic and differentials included a poorly differentiated carcinoma (90% certainty) or a sarcoma.

Image 3: Multiple round to stellate to occasionally fusiform shaped, individual and clustered, neoplastic cells predominate. The cells exhibit moderate to marked anisocytosis and anisokaryosis, have basophilic cytoplasm, a large round to ovoid nucleus, coarse chromatin in one or more prominent nucleoli.

Case management:

The patient was referred to the oncology services. Thoracic radiographs did not reveal the presence of metastatic lesions. Exploratory surgery was pursued but complete resection of the lesion could not be achieved. Intra-operative biopsies were obtained and histopathology evaluation revealed pancreatic adenocarcinoma.

Pancreatic adenocarcinoma is an uncommon neoplasm seen in cats. In a retrospective study of 34 cases, the most common presenting clinical signs included weight loss, decreased appetite, vomiting, palpable abdominal mass and diarrhea. Only a small number of patients had elevations of the pancreatic enzymes. Ultrasound was proven to be a sensitive diagnostic tool with pancreatic abnormalities detected in 33 patients. Metastatic disease was present in 11 cats. The overall median survival was 97 days with only 3 patients surviving over 1 year. The median survival times for patients who received chemotherapy (mainly gemcitabine or a combination of gemcitabine/carboplatin) or had their masses surgically removed was 165 days. This study confirmed that exocrine pancreatic carcinoma in cats is an aggressive tumor with a high metastatic rate and poor prognosis.
Linderman MJ, Brodsky EM, deLorimier L-P, et al. Feline exocrine pancreatic carcinoma: a retrospective study of 34 cases. Vet Comp Oncol 2013;11(3):208-218.

Progression and outcome:

Oral administration of the chemotherapeutic agent toceranib phosphate (Palladia) was instituted post-surgery in addition to supportive medical therapy. Unfortunately, the patient’s clinical condition continued to deteriorate and humane euthanasia was elected approximately a month following the initial ultrasound diagnosis.

Special thanks to Dr. Homan and the staff at Seneca Hill Animal Hospital, Dr. Leblanc at Eastern Veterinary Pathology, and Dr. McNeil at the Hope Advanced Veterinary Center for their help with this case.