title: Clinical, pathologic, and immunohistochemical prognostic factors in dogs with thyroid carcinoma.
abstract: BACKGROUND
  Prognostic markers for dogs with thyroid tumors are limited.
  
  
  OBJECTIVE
  To identify clinical, pathologic, and immunohistochemical prognostic factors for dogs with thyroid tumors.
  
  
  METHODS
  Seventy dogs with thyroid neoplasia.
  
  
  METHODS
  Retrospective study. Dogs with thyroid neoplasia were included when follow-up information and formalin-fixed paraffin-embedded tumor samples were available. Immunohistochemistry (IHC) was performed for thyroglobulin, calcitonin, Ki-67, and E-cadherin. Correlation of tumor variables (diameter, volume, localization, scintigraphic uptake, thyroid function, IHC) with local invasiveness and metastatic disease was performed on all tumor samples. Forty-four dogs treated by thyroidectomy were included in a survival analysis.
  
  
  RESULTS
  Fifty dogs (71%) had differentiated follicular cell thyroid carcinoma (dFTC) and 20 (29%) had medullary thyroid carcinoma (MTC). At diagnosis, tumor diameter (P = .007; P = .038), tumor volume (P = .020), tumor fixation (P = .002), ectopic location (P = .002), follicular cell origin (P = .044), and Ki-67 (P = .038) were positively associated with local invasiveness; tumor diameter (P = .002), tumor volume (P = .023), and bilateral location (P = .012) were positively associated with presence of distant metastases. Forty-four dogs (28 dFTC, 16 MTC; stage I-III) underwent thyroidectomy. Outcome was comparable between dogs with dFTC and MTC. Macroscopic (P = .007) and histologic (P = .046) vascular invasion were independent negative predictors for disease-free survival. Although time to presentation, histologic vascular invasion and Ki-67 were negatively associated with time to metastases, and time to presentation was negatively associated with time to recurrence, no independent predictors were found. E-cadherin expression was not associated with outcome.
  
  
  CONCLUSIONS
  Prognostic factors have been identified that provide relevant information for owners and clinicians.
authors.affiliation: Department of Medicine and Clinical Biology of Small Animals, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Campos
authors.forename: R
authors.initials: R
authors.lastname: Ducatelle
authors.forename: G
authors.initials: G
authors.lastname: Rutteman
authors.forename: H S
authors.initials: HS
authors.lastname: Kooistra
authors.forename: L
authors.initials: L
authors.lastname: Duchateau
authors.forename: H
authors.initials: H
authors.lastname: de Rooster
authors.forename: K
authors.initials: K
authors.lastname: Peremans
authors.forename: S
authors.initials: S
authors.lastname: Daminet
mesh_terms: D018263:Adenocarcinoma, Follicular / Q000737:chemistry / Q000175:diagnosis / Q000401:mortality / Q000473:pathology / Q000601:surgery / Q000662:veterinary; D000818:Animals; D015820:Cadherins / Q000032:analysis; D002116:Calcitonin / Q000032:analysis; D018278:Carcinoma, Neuroendocrine / Q000737:chemistry / Q000175:diagnosis / Q000401:mortality / Q000473:pathology / Q000601:surgery / Q000662:veterinary; D004283:Dog Diseases / Q000175:diagnosis / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D004285:Dogs; D019394:Ki-67 Antigen / Q000032:analysis; D011379:Prognosis; D012189:Retrospective Studies; D016019:Survival Analysis; D013954:Thyroglobulin / Q000032:analysis; D013961:Thyroid Gland / Q000737:chemistry / Q000473:pathology; D013964:Thyroid Neoplasms / Q000737:chemistry / Q000175:diagnosis / Q000401:mortality / Q000473:pathology / Q000601:surgery / Q000662:veterinary*; D013965:Thyroidectomy / Q000401:mortality / Q000662:veterinary
chemical_list: D015820:Cadherins; D019394:Ki-67 Antigen; D002116:Calcitonin; D013954:Thyroglobulin
keywords: Calcitonin; E-cadherin; Follicular; Ki-67; Medullary