Multiple inflammatory gastric polyps treated by endoscopic polypectomy with argon plasma coagulation in a dog

First description of oesophageal melanoma in a cat and palliative treatment by endoscopic argon plasma coagulation laser

Case summary

An 11-year-old castrated male domestic shorthair cat presented with chronic regurgitation and weight loss. Despite a 2-month history of weight loss, regurgitation intensified over 4 weeks, occurring with every food intake, even on a semi-liquid diet. Physical examination revealed thinness and dehydration, and a focal oval mass was noted in the middle mediastinum on thoracic radiography. Oesophagoscopy identified a 6 cm neoformation almost completely obstructing the oesophageal lumen. Biopsies were taken and histopathology, positivity to melanoma triple cocktail and PNL-2 by immunohistochemistry led to the diagnosis of melanocytic neoplasm. Palliative debulking with argon plasma coagulation (APC) was performed, significantly improving the cat's quality of life for 2 months. The cat survived for 107 days after diagnosis.

Relevance and novel information

This case report describes the first report of melanocytic neoplasia originating from the oesophageal mucosa in a cat. In cats, melanomas outside the eyes are exceedingly rare and oesophageal neoplasms are exceptionally rare in veterinary medicine, particularly melanomas. The diagnosis relied on positive immunohistochemistry markers aligning with previous research. Treatment with APC emerged as a novel, potentially palliative approach, successfully alleviating regurgitation for 3 months. This underscores APC's potential in feline oesophageal neoplasia palliative care, which deserves further investigation in a broader feline cohort to confirm its efficacy. Overall, this report provides valuable insights into the diagnosis and treatment of oesophageal melanoma in cats.

Equine Gastric Squamous Cell Carcinoma in a Friesian Stallion

A 7-year-old Friesian stallion with a history of oesophageal stenosis, weight loss, inappetence, and recurrent hyperthermia was referred for gastroscopy. The stomach mucosa surrounding the oesophageal opening showed a large, necrotic, and ulcerated mass. On post-mortem examination, a very large, cauliflower-like neoplasm was seen, affecting non-glandular gastric mucosa. Nodular lesions were observed, scattered on the omentum, the spleen and the liver. Microscopic findings allowed the diagnosis of gastric squamous cell carcinoma with abdominal metastasis. Biomolecular investigations demonstrated the presence of EcPV-2 genes in neoplastic lesions, thus supporting the role of EcPV-2 in the ethiology of equine gastric cancer.

Endoscopic Endocautery Polypectomy for the Treatment of Duodenal and Gastric Polyps in a Cat

Endoscopic polypectomy is commonly performed in human medicine, with large-scale studies reported. However, few reports have described its use in veterinary medicine and, specifically, the procedure in the case of duodenal polyps in cats has not been reported. A 7 kg 14-year-old cat presented with recurrent vomiting for several months. Gastroduodenoscopy revealed a pedunculated polyp at the pyloric antrum and another in the duodenum, with its head protruding into the pylorus. Endoscopic polypectomy was performed using an electrosurgical snare with no recurrence of clinical signs after six months. Duodenal polypectomy in cats may be difficult because of space limitation but it can be safe, minimally invasive, and successful, thus avoiding more invasive surgical techniques. Endoscopic polypectomy may be a viable alternative to surgery in cats with gastric and duodenal polyps.

Use of endoscopic-assisted argon plasma coagulation for the treatment of colonic vascular ectasia (angiodysplasia) in an adult dog

CASE DESCRIPTION

A 10-year-old neutered male mixed-breed dog was evaluated for a 5-year history of intermittent hematochezia and chronic anemia that were unresponsive to medical treatment.

CLINICAL FINDINGS

Colonoscopy revealed multifocal areas of coalescing tortuous mucosal blood vessels throughout the colon and rectum. Colonic vascular ectasia (angiodysplasia) was diagnosed on the basis of the endoscopic appearance of the lesions.

TREATMENT AND OUTCOME

The dog failed to respond to traditional medical treatments for colonic vascular ectasia and required multiple plasma and blood transfusions. The dog received 4 endoscopic-assisted argon plasma coagulation treatments, which resulted in long-term resolution of gastrointestinal hemorrhage. Colonic perforation occurred during the third argon plasma coagulation treatment. The perforation was surgically repaired. The dog remained free from clinical signs of colonic vascular ectasia for > 1 year after the third argon plasma coagulation treatment and was euthanized because of clinical deterioration associated with progressive heart disease.

CLINICAL RELEVANCE

Endoscopic-assisted argon plasma coagulation treatment is a novel treatment for dogs with colonic vascular ectasia and provided long-term resolution of clinical signs for the dog of this report. In human patients, complications associated with endoscopic-assisted argon plasma coagulation treatment include colonic perforation, which also occurred in the dog of this report.