title: Prospective evaluation of biweekly streptozotocin in 19 dogs with insulinoma.
abstract: BACKGROUND
  Administration of streptozotocin (STZ) at a 21-day interval has been described in dogs with stage II and III insulinoma. Myelosuppression was not observed, suggesting the possibility of increasing dose intensity by decreasing the interval between doses.
  
  
  OBJECTIVE
  To describe the tolerability of a biweekly STZ protocol. A secondary objective was to describe the outcome of dogs treated with this protocol.
  
  
  METHODS
  Nineteen dogs with residual local, metastatic, or recurrent insulinoma.
  
  
  METHODS
  After surgery for insulinoma, or at the time of recurrence, dogs were treated with a previously described STZ and saline diuresis protocol. Treatments were administered every 14 days. All dogs received antiemetic treatment. Adverse events (AEs) were recorded and graded. Outcome endpoints assessed were progression-free survival (PFS) and survival.
  
  
  RESULTS
  None of the dogs experienced neutropenia or thrombocytopenia. Mild to moderate gastrointestinal toxicity was the most common AE. Diabetes mellitus was observed in 8 dogs and, in 6, resulted in euthanasia or death. Two dogs developed nephrotoxicity manifested as Fanconi syndrome in 1 and nephrogenic diabetes insipidus in the other. Six dogs developed increased alanine amino transferase activity. Hypoglycemia at the end of the STZ infusion, resulted in collapse in 1 dog and a generalized seizure in another. The median overall PFS and survival time were 196 and 308 days, respectively.
  
  
  CONCLUSIONS
  Streptozotocin can be safely administered to dogs with insulinoma, but serious AEs are possible. Additional investigation is required to better define the role of STZ in managing dogs with insulinoma.
authors.affiliation: Department of Small Animal Medicine and Surgery, University of Georgia, College of Veterinary Medicine, Athens, GA 30602, USA. northrup@uga.edu
authors.forename: N C
authors.initials: NC
authors.lastname: Northrup
authors.forename: K M
authors.initials: KM
authors.lastname: Rassnick
authors.forename: T L
authors.initials: TL
authors.lastname: Gieger
authors.forename: C E
authors.initials: CE
authors.lastname: Kosarek
authors.forename: C W
authors.initials: CW
authors.lastname: McFadden
authors.forename: M P
authors.initials: MP
authors.lastname: Rosenberg
mesh_terms: D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D005260:Female; D007340:Insulinoma / Q000188:drug therapy / Q000662:veterinary*; D008297:Male; D013311:Streptozocin / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000903:Antibiotics, Antineoplastic; D013311:Streptozocin