Retrospective Study of Computed Tomographic Characterization of Canine Oral Malignant Melanoma in 24 Dogs

Abstract

Clinical and computed tomographic (CT) information from 24 histopathological diagnosed canine oral malignant melanomas (MMs) was retrospectively investigated. The CT appearance on canine oral MM from each patient was evaluated, including both bone and soft tissue windows and pre- and post-contrast enhancement. Among the 24 dogs, canine oral MM was highly presented in small breeds, especially in miniature dachshunds older than 10 years. The gingiva was the most commonly affected site, followed by palatine, mucosal, and lingual areas. The location of the primary tumor in the oral arcade was statistically significant associated with bone invasion such as osteolysis. Canine oral MMs in the caudal arcades showed significantly greater association with osteolysis than MMs of the rostral arcades (p = 0.0325). Among tumor locations, the upper oral arcades had a significantly higher contrast enhancement value than the lower arcades (p = 0.0228). When metastatic and non-metastatic regional lymph nodes were compared, there was no significant difference in node size or contrast enhancement values, although metastatic mandibular lymph nodes were slightly larger than the non-metastatic nodes. Therefore, CT-based information could facilitate clinical diagnosis and treatment planning for canine oral MM.