title: Use of a self-expanding metallic stent to palliate esophageal neoplastic obstruction in a dog.
abstract: METHODS
  An 11-year-old spayed female Collie was evaluated because of regurgitation, dysphagia, severe ptyalism, coughing, and weight loss of approximately 12 weeks' duration. Esophageal squamous cell carcinoma had been diagnosed prior to referral on the basis of results of radiographic and endoscopic examination and histologic evaluation of biopsy samples. A percutaneous endoscopically placed gastrostomy (PEG) tube had been inserted 2 weeks prior to referral, and the dog was being treated for infection at the gastrostomy site.
  
  
  RESULTS
  Physical examination findings included marked ptyalism, stertor, and inflammation and discharge at the gastrostomy site.
  
  
  RESULTS
  Surgical options were declined by the owner, and palliative treatment was chosen to alleviate clinical signs and facilitate PEG tube removal. With fluoroscopic guidance, a self-expanding metallic stent was placed in the esophageal lumen at the site of obstruction. Botulinum toxin A was injected into the mandibular salivary glands under ultrasonographic guidance as treatment for severe ptyalism. Following discharge, clinical improvement was reported until euthanasia for unrelated disease 12 weeks after stent placement. Necropsy revealed that the stent had not migrated and had remained patent with some tumor ingrowth but no evidence of stricture or obstruction.
  
  
  CONCLUSIONS
  Esophageal stenting effectively treated obstruction and improved clinical signs and may be beneficial for palliative treatment in other animals with malignant esophageal tumors. Although the degree to which botulinum toxin A injection into salivary glands improved clinical signs could not be determined, it may potentially be useful as adjunctive treatment to reduce severe ptyalism.
authors.affiliation: Department of Radiation Oncology, Medical Center, School of Medicine, Duke University, Durham, NC 27710, USA. kshansen@ucdavis.edu
authors.forename: Katherine S
authors.initials: KS
authors.lastname: Hansen
authors.forename: Chick
authors.initials: C
authors.lastname: Weisse
authors.forename: Allyson C
authors.initials: AC
authors.lastname: Berent
authors.forename: Marilyn
authors.initials: M
authors.lastname: Dunn
authors.forename: Ana V
authors.initials: AV
authors.lastname: Caceres
authors.forename: Kim L
authors.initials: KL
authors.lastname: Todd
authors.forename: Jeremy S
authors.initials: JS
authors.lastname: Diroff
mesh_terms: D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000150:complications / Q000628:therapy / Q000662:veterinary*; D003680:Deglutition Disorders / Q000209:etiology / Q000628:therapy / Q000662:veterinary*; D004283:Dog Diseases / Q000628:therapy*; D004285:Dogs; D004938:Esophageal Neoplasms / Q000150:complications / Q000628:therapy / Q000662:veterinary*; D004940:Esophageal Stenosis / Q000150:complications / Q000628:therapy / Q000662:veterinary*; D005260:Female; D010166:Palliative Care; D015607:Stents / Q000662:veterinary*; D016896:Treatment Outcome