Canine melanoma is a malignant cancer affecting dogs, especially in the oral cavity, digits, and skin. This study investigated survival outcomes in 123 dogs diagnosed with melanoma at a veterinary teaching hospital in Japan between April 1, 2004, and March 31, 2023. Data were retrospectively obtained from electronic clinical records, with survival analysis performed using Kaplan-Meier curves, log-rank tests, and parametric survival models. The median survival time (MST) for all dogs was 244 days. Dogs that underwent surgical tumor removal had significantly longer survival (MST: 294 days) compared to those without surgery (MST: 93 days, P<0.001). The final parametric model with a log-logistic distribution identified tumor stage, location, and breed as key prognostic factors. Miniature Schnauzers and Toy Poodles had 3.36 and 4.80 times longer survival times, respectively, compared to Golden Retrievers. Oral melanomas were associated with a 66% shorter survival time than non-oral melanomas (median survival times: 191 vs. 663 days; P=0.019). Advanced melanoma stages significantly decreased survival; time ratios for stage III and stage IV compared to stage I were 0.60 (95% confidence interval CI: 0.33-1.07; P-value: 0.084) and 0.42 (95% CI: 0.22-0.77; P-value: 0.006), respectively. These findings enhance understanding of canine melanoma in Japan and emphasize the need for multi-center studies to confirm these results.
Teng et al. (Thu,) studied this question.