Canine gastrinoma: A case study and literature review of therapeutic options

CASE HISTORY: A 6.2 kg, 8-year-old, spayed female Australian Terrier was presented with weight loss, inappetence, lethargy and a 2-day history of intermittent vomiting. CLINICAL FINDINGS: The dog had cranial abdominal pain and there was melaena present on digital rectal examination. Haematology revealed a marked, acute leucogram. DIAGNOSIS AND TREATMENT: Fasting serum gastrin levels were markedly elevated and gastrinoma was suspected. Treatment was initiated with omeprazole, ranitidine and sucralfate. The dog remained clinically normal for 26 months, at which time exploratory surgery was undertaken and the dog subsequently euthanised due to extensive metastases. Histopathology and immunocytochemistry confirmed the diagnosis of metastatic gastrinoma. CLINICAL RELEVANCE: This is a rare condition infrequently reported. Although the number of cases treated with omeprazole are too few to draw firm conclusions, it would appear that proton pump inhibitors are useful and should be considered for cases of gastrinoma managed medically. Long-term prognosis is poor, and survival times range from 1 to 147 weeks. Many treatment options are discussed in the medical literature though not all are feasible in veterinary patients.