title: Intensity-modulated and image-guided radiation therapy for treatment of genitourinary carcinomas in dogs.
abstract: BACKGROUND
  External beam radiation therapy can be used to treat pelvic tumors in dogs, but its utility is limited by lack of efficacy data and associated late complications.
  
  
  OBJECTIVE
  The objective of this study was to assess local tumor control, overall survival, and toxicosis after intensity-modulated and image-guided radiation therapy (IM/IGRT) for treatment of genitourinary carcinomas (CGUC) in dogs.
  
  
  METHODS
  21 client-owned dogs.
  
  
  METHODS
  A retrospective study was performed. Medical records of dogs for which there was intent to treat with a course of definitive-intent IM/IGRT for CGUC between 2008 and 2011 were reviewed. Descriptive and actuarial statistics comprised the data analysis.
  
  
  RESULTS
  Primary tumors were located in the prostate (10), urinary bladder (9), or urethra (2). The total radiation dose ranged from 54-58 Gy, delivered in 20 daily fractions. Grade 1 and 2 acute gastrointestinal toxicoses developed in 33 and 5% of dogs, respectively. Grade 1 and 2 acute genitourinary and grade 1 acute integumentary toxicoses were documented in 5, 5, and 20% of dogs, respectively. Four dogs experienced late grade 3 gastrointestinal or genitourinary toxicosis. The subjective response rate was 60%. The median event-free survival was 317 days; the overall median survival time was 654 days. Neither local tumor control nor overall survival was statistically dependent upon location of the primary tumor.
  
  
  CONCLUSIONS
  IM/IGRT is generally well-tolerated and provides an effective option for locoregional control of CGUC. As compared with previous reports in the veterinary literature, inclusion of IM/IGRT in multimodal treatment protocols for CGUC can result in superior survival times; controlled prospective evaluation is warranted.
authors.affiliation: Department of Environmental and Radiologic Health Sciences, College of Veterinary Medicineand Biomedical Sciences, Fort Collins, CO, USA. Michael.Nolan@colostate.edu
authors.forename: M W
authors.initials: MW
authors.lastname: Nolan
authors.forename: L
authors.initials: L
authors.lastname: Kogan
authors.forename: L R
authors.initials: LR
authors.lastname: Griffin
authors.forename: J T
authors.initials: JT
authors.lastname: Custis
authors.forename: J F
authors.initials: JF
authors.lastname: Harmon
authors.forename: B J
authors.initials: BJ
authors.lastname: Biller
authors.forename: S M
authors.initials: SM
authors.lastname: Larue
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000473:pathology / Q000532:radiotherapy*; D004285:Dogs; D005260:Female; D053208:Kaplan-Meier Estimate; D008297:Male; D061089:Radiotherapy, Image-Guided / Q000009:adverse effects / Q000379:methods / Q000662:veterinary*; D012189:Retrospective Studies; D016019:Survival Analysis; D014565:Urogenital Neoplasms / Q000473:pathology / Q000532:radiotherapy / Q000662:veterinary*