**4. Prognostic factors for canine melanomas**

A histological and epidemiological study including 384 cases of melanocytic tumors comprised 19% oral tumors, of which 59% were malignant. In contrast, analyses of melanocytic tumors of the skin identified only 12% of patients with malignant tumor [6]. Regarding the prognostic criteria for canine melanoma, mitotic

#### *Immunology of Canine Melanoma DOI: http://dx.doi.org/10.5772/intechopen.108430*

index, nuclear atypia, tumor volume, the presence of metastasis, and the presence of deep inflammation or intralesional necrosis remain pivotal when determining patient outcome [6, 9].

A previous study of 67 oral melanoma samples suggested that free surgical margins and chemotherapy with carboplatin increased patient survival [16]. Another study indicated that melanocytic tumors were more common in middle-aged dogs with dark hair and undefined breeds. Histological analysis also revealed the prevalence of epithelioid cells [17]. Another study evaluated 338 canine oral melanoma cases, with an overrepresentation of breeds, such as Chow, Golden Retriever, and Pekingese/Poodle mix, but with no mention of hair color. Histological evaluation suggested the presence of polygonal and spindle cells [18]. However, the mismatched results suggested that epidemiological data for canine oral melanoma require detailed evaluation.
