Abstract
Mammary tumors are common neoplasms in female dogs and pose a clinical challenge because of their high malignancy potential. This retrospective study analyzed the medical records of 724 female dogs with 1,638 mammary tumors treated between 2012 and 2022 to assess epidemiological and clinicopathological associations. Malignant tumors (84.6%) were larger than benign ones (3.4 cm vs. 2.3 cm, P<0.01) and were associated with advanced age, multiple tumors, size >5 cm, and ulceration. Tumors >5 cm in size were associated with histological grade III, ulceration, adhesion, and regional metastases. In the multivariate analysis, tumor malignancy was 3.2 times more likely with each additional tumor, 3.3 times more likely with each additional year of age, and 4.8 times more likely with ulcerated tumors. These findings highlight the importance of early diagnosis, comprehensive evaluation, and regular monitoring, especially in high-risk dogs such as elderly and overweight female dogs.
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