Introduction

Mammary tumors are the most prevalent tumor in bitches, affecting mainly middle-aged and older female canines. Carcinoma in mixed tumors and tubular carcinoma are the most common histological types diagnosed in bitches.

Objectives

Report a rare case of mammary carcinoma in a young bitch and verify protein expression of VEGF (vascular endothelial growth factor), ATM, p53, c-KIT and cycloxygenase-2 (COX-2) and clinical features (tumor ulceration, clinical staging and reproductive status).

Methods

A 1,5-year-old, Pinscher female dog, intact, without contraceptive usage with a non-ulcerating tubular mammary carcinoma grade I with clinical stage I was attended in the FCAV Veterinary Hospital, Jaboticabal/SP/Brazil and treated with mastectomy. Protein expression of tumor samples were analyzed for VEGF, ATM, p53, c-KIT and COX-2 by immunohistochemistry performed by the distribution of positively immunostained tumor cells in scores: 1 (< 25% cells positive), 2 (26% to 50% cells positive), 3 (51% to 75% cells positive) and 4 (> 75% cells positive) with cytoplasmic (VEGF, ATM, c-KIT and COX-2) or nuclear (p53) immunostained.

Results

All these markers presented score 3. High expression of ATM, p53 (tumor suppressors) and c-KIT are associated with better prognoses in women with breast cancer, while high levels of VEGF and COX-2 are correlated with invasion and metastasis. This dog presents 26 months survival until now.

Conclusions

Prognostic factors evaluated showed a favorable behavior for this patient, including the clinical features. Differently in young women, breast cancers tend to be more aggressive.

Grant 2013/03940-4, São Paulo Research Foundation (FAPESP)