Mammary Neoplasms in Male Dogs: A 24-year Descriptive study.

Abstract

Mammary neoplasms in male dogs are as rare as in humans, accounting for less than 1% of all tumors. In a descriptive review of cases diagnosed between 2000 and June 2024, 2,172 mammary neoplasms were identified, of which only four (0.18%) occurred in male dogs. The patients ranged in age from 8 to 11 years, with a mean age of 9.7 years. Histopathological analysis revealed that 75% (3/4) of the cases were malignant, while 25% (1/4) were benign. Among the malignant cases, only one patient exhibited regional metastases. Two patients had concurrent testicular neoplasia, both diagnosed as Leydig cell tumors. Malignant histological subtypes included carcinosarcoma, tubular carcinoma, and carcinoma within a mixed tumor. The only benign tumor identified was a benign mixed tumor. All malignant neoplasms exhibited high expression of hormone receptors, highlighting their potential role in tumor development. Additionally, cyclooxygenase-2 (COX-2) expression, a potential therapeutic target and prognostic factor, was observed. Early diagnosis is crucial for improving prognosis; however, due to the rarity of this condition, diagnosis is often delayed. These findings emphasize the occurrence of these neoplasms in male dogs, and report on complementary techniques to improve therapeutic strategies.