Retrospective Analysis of Prevalence of Tumors in Dogs and Cats in Lithuania

The objective of this study was to assess the prevalence and clinicopathological characteristics of tumors in dogs and cats in Lithuania. A total of 3525 routine diagnostic samples collected from 1 January 2020 to 1 July 2025 were microscopically examined and statistically analyzed. Tumor prevalence was slightly higher in dogs (59.2%, <i>n</i> = 1693) compared with cats (56.5%, <i>n</i> = 375). Mammary gland tumors, skin tumors, and sarcomas were the most common neoplasms in both species, although notable interspecies differences were identified. In particular, feline mammary carcinomas were more aggressive, and squamous cell carcinoma was significantly more frequent in cats. These findings are consistent with international epidemiological trends and highlight the importance of species-specific diagnostic and management strategies.