title: Surgically planned versus histologically measured lateral tumor margins for resection of cutaneous and subcutaneous mast cell tumors in dogs: 46 cases (2010-2013).
abstract: OBJECTIVE
  To compare preplanned lateral surgical margins and measured lateral histologic margins for cutaneous and subcutaneous mast cell tumor (MCT) resections in dogs.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  51 biopsy specimens from dogs (n = 46) with MCTs.
  
  
  METHODS
  All canine patients that underwent curative-intent surgical resection of cutaneous or subcutaneous MCTs from January 1, 2010, through June 30, 2013, with complete medical records including signalment, body condition score (BCS), surgery report (with measured surgical margins), and histopathology report were included. The surgically measured tumor margins in each quadrant were grouped and compared with the corresponding histologic margins. Specimens from dogs with truncal MCTs and a BCS of 7 to 9 on a scale from 1 to 9 (ie, high) were compared with those of dogs with a BCS of 4 to 6 to evaluate effect of BCS on tissue margins.
  
  
  RESULTS
  51 specimens were included. Surgically mapped lateral margins differed significantly from histologically reported margins in all 4 quadrants. The mean histologic margins were 35% to 42% smaller than the surgical margins for the combined 51 specimens. A higher BCS did not significantly influence the magnitude of the decrease in lateral margins measured histologically. No significant difference was found for the magnitude of the differences between any of the 4 lateral margins.
  
  
  CONCLUSIONS
  Results of this study suggested that surgical and histologic margins may differ significantly for canine cutaneous and subcutaneous MCTs. This may be a result of tissue shrinkage following excision and fixation, extension of the MCT beyond palpable margins, or both. Histologic measurements may significantly underestimate the tumor-free margins in dogs with cutaneous and subcutaneous MCTs.
authors.forename: Marije
authors.initials: M
authors.lastname: Risselada
authors.forename: Kyle G
authors.initials: KG
authors.lastname: Mathews
authors.forename: Emily
authors.initials: E
authors.lastname: Griffith
mesh_terms: D000818:Animals; D062109:Dermatologic Surgical Procedures / Q000662:veterinary; D004283:Dog Diseases / Q000473:pathology / Q000601:surgery*; D004285:Dogs; D005260:Female; D008297:Male; D034701:Mastocytosis, Cutaneous / Q000601:surgery / Q000662:veterinary*; D009367:Neoplasm Staging; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000601:surgery / Q000662:veterinary*; D013048:Specimen Handling