Use of a self-expanding metallic stent to palliate esophageal neoplastic obstruction in a dog.

CASE DESCRIPTION: 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. CLINICAL FINDINGS: Physical examination findings included marked ptyalism, stertor, and inflammation and discharge at the gastrostomy site. TREATMENT AND OUTCOME: 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. CLINICAL RELEVANCE: 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.

Evaluation of palliative stenting for management of malignant urethral obstructions in dogs.

OBJECTIVE: To evaluate use of balloon-expandable and self-expanding metallic stents in management of malignant urethral obstructions in dogs. DESIGN: Original study. ANIMALS: 12 dogs with malignant urethral obstructions. PROCEDURES: The extent and location of urethral obstructions and the diameter of adjacent unaffected luminal segments were determined by use of fluoroscopically guided wires and measuring catheters. Stents were chosen to extend approximately 1 cm proximal and distal to the obstruction. Stent diameters were chosen to be approximately 10% greater than the diameter of healthy portions of the urethra to prevent displacement. Stents were placed in the urethra under fluoroscopic guidance to restore luminal patency. RESULTS: 3 dogs received balloon-expandable metallic stents, and 9 dogs received self-expanding metallic stents. The placement procedures were rapid, safe, and effective at restoring luminal patency and were not associated with major complications. Complications included recurrent urethral obstruction secondary to blood clot formation and urethral edema in 1 dog and stent dislodgement into the urinary bladder in 1 dog. All dogs were able to urinate immediately after the procedure. Nine dogs (3/4 females and 6/8 males) were continent or mildly incontinent after stent placement. Of the remaining 3 dogs, 2 developed severe incontinence and 1 had an atonic bladder. Seven dogs were considered to have good to excellent outcome, 3 had fair outcome, and 2 had poor outcome. CONCLUSIONS AND CLINICAL RELEVANCE: Transurethral placement of metallic stents was a safe and effective palliative treatment option for dogs with malignant urethral obstructions.