We performed an endoscopic examination of the nasal cavity through the choanae (internal nostrils) of 20 dogs with nasal disease and the findings were classified into three categories: tumorous, inflammatory or normal tissue. Based on the endoscopic findings, a tentative diagnosis of tumorous tissue was obtained in eight cases, inflammation was detected in 10 cases, and a normal phenotype was diagnosed in two cases. The results were then compared with the histopathological findings from tissue samples obtained by endoscopic examination through the choanae of the same 20 dogs. A definitive histopathological diagnosis was obtained in 95% (19/20) of the cases, and the concordance rate between the endoscopic findings and definitive histopathology was 85%. Based on the results of this study, endoscopic examination of the nasal cavity through the choanae is proposed as a useful tool for diagnosing nasal disease in dogs.

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An 11-year-old castrated male Shih-Tzu presented with a rapidly-growing mandibular mass. A hard gingival mass of 2.7 × 1.5 cm in size was present on the rostral mandible in the vicinity of the incisors and both canines. Bone resorption was detected on radiographs. An excisional biopsy was performed at first admission and the mass was diagnosed as an amyloid-producing odontogenic tumor (APOT). The mass had grown to 3.3 × 3.0 cm in size by 14 days after first admission and was excised by bilateral rostral mandibulectomy, with an incision made between the second and third premolar teeth. Histopathology identified small nests or cords of odontogenic epithelial cells, and marked deposition of amyloid based on Congo-red staining. These findings suggest that the rapid growth of the gross lesion resulted from both cell proliferation and marked amyloid production. Complete removal of the APOT lesion was histologically indicated, and neither recurrence nor metastasis was observed for 49 months after surgery. Therefore, early wide excision, including rostral mandibulectomy, should be considered a useful treatment for locally invasive, rapidly growing APOT in dogs.

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An 8-month-old female cat presented with a 1-month history of open-mouth breathing and intermittent regurgitation. Contrast radiography revealed megaesophagus (ME) with a large pharyngeal mass. The mass was removed by gentle traction under general anesthesia, after which the ME resolved within 9 days. The mass was diagnosed as a nasopharyngeal polyp based on clinical and histopathological findings. A similar polyp recurred 50 days postoperatively, and was also removed by traction followed by four treatments with methylprednisolone acetate. The cat remained asymptomatic for 9 months after the second surgery. This report demonstrates that ME resulting from a nasopharyngeal polyp may resolve spontaneously after polyp removal, but post-surgical glucocorticoid therapy may also be needed to decrease the chance of recurrence.

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A 13-year-old spayed female cat presented for chronic vomiting and weight loss. Ultrasonic examination identified an abdominal mass likely originating from thickened small intestine. Laparotomy revealed a mass involving ileum, cecum, and ascending colon. Affected tissues were resected, followed by end-to-end ileocolic anastomosis. Grossly, an abscess that did not continue to the intestinal lumen was present in the central area of the resected mass, from which Clostridium perfringens was isolated. Histopathologically, the area surrounding the abscess contained dense collagen trabeculae with marked eosinophilic infiltration, enabling diagnosis of feline gastrointestinal eosinophilic sclerosing fibroplasia (FGESF). Chronic vomiting almost resolved after surgery and body weight gradually increased. Administration of predonisolone was continued for 26 months to control mild enteritis. FGESF should be considered as a differential diagnosis for cats with abdominal mass, and treatment by surgical resection should be considered because of the possibility of intralesional bacterial infection.

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