INSULIN-SECRETING TUMORS OF THE CANINE PANCREAS - CLINICAL AND PATHOLOGICAL FEATURES OF 11 CASES

This paper describes the clinical and pathological features of 11 dogs with insulin-secreting tumours of the pancreas. All the dogs showed e pisodic weakness or collapse. The diagnosis was made on fasting plasma glucose and serum insulin concentrations, the insulin:glucose ratio, and the results of an intravenous glucose tolerance test. Ten of the d ogs had exploratory laparotomy, and partial pancreatectomy was perform ed in nine of the cases. One case was euthanased at surgery because of widespread metastases. The tumours were graded histologically and the results compared with the time to recurrence of clinical signs and po stoperative survival time. Postoperative survival time for dogs which died or were euthanased as a direct result of tumour recurrence, and t ime to recurrence of clinical signs were calculated from actuarial sur vival curves. The median time to recurrence of clinical signs after su rgery was 12 months (range from four to 16 months; mean time to recurr ence of clinical signs 12 months). Two cases died of unrelated disease , without recurrence of hypoglycaemic signs. The median postoperative survival time was 14 months (range 10 to 33 months; mean survival time 15 months). There is a suggestion that tumours with a high mitotic co unt carried a worse prognosis.