title: The impact of pamidronate and chemotherapy on survival times in dogs with appendicular primary bone tumors treated with palliative radiation therapy.
abstract: OBJECTIVE
  To assess survival times in dogs that received palliative radiation therapy (RT) alone, and in combination with chemotherapy, pamidronate, or both for primary appendicular bone tumors and determine whether the addition of these adjunctive therapies affects survival.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  Dogs (n = 50) with primary appendicular bone tumors.
  
  
  METHODS
  Dogs were divided into the following treatment groups: RT alone, RT + chemotherapy, RT+ pamidronate, and RT+ chemotherapy + pamidronate. Dogs were considered for analysis if they had a known euthanasia date or follow-up data were available for at least 120 days from the time of diagnosis. Survival time was defined as the time from admission to euthanasia. Cox proportional hazard models and Kaplan-Meier survival functions were used. A P value of less than .05 was considered significant.
  
  
  RESULTS
  Fifty dogs were considered for survival analysis. Median survival times (MSTs) were longest for dogs receiving RT and chemotherapy (307 days; 95% CI: 279, 831) and shortest in dogs receiving RT and pamidronate (69 days; 95% CI: 47, 112 days). The difference in MST between dogs who received pamidronate and those who did not in this population was statistically significant in a univariate (P = .039) and multivariate analysis (P = .0015). The addition of chemotherapy into any protocol improved survival (P < .001).
  
  
  CONCLUSIONS
  Chemotherapy should be recommended in addition to a palliative RT protocol to improve survival of dogs with primary appendicular bone tumors. When combined with RT ± chemotherapy, pamidronate decreased MST and should not be included in a standard protocol.
authors.affiliation: Department of Clinical Studies, Ontario Veterinary College, Guelph, Canada. moblak@uoguelph.ca
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Oblak
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Boston
authors.forename: Geraldine
authors.initials: G
authors.lastname: Higginson
authors.forename: Steven G
authors.initials: SG
authors.lastname: Patten
authors.forename: Gabrielle J
authors.initials: GJ
authors.lastname: Monteith
authors.forename: J Paul
authors.initials: JP
authors.lastname: Woods
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001859:Bone Neoplasms / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy / Q000662:veterinary*; D003131:Combined Modality Therapy / Q000662:veterinary; D004164:Diphosphonates / Q000627:therapeutic use*; D004283:Dog Diseases / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D004285:Dogs; D005260:Female; D008297:Male; D012516:Osteosarcoma / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy / Q000662:veterinary*; D010166:Palliative Care / Q000379:methods; D000077268:Pamidronate; D012189:Retrospective Studies; D016019:Survival Analysis
chemical_list: D000970:Antineoplastic Agents; D004164:Diphosphonates; D000077268:Pamidronate