Contribuição para o estudo da biopatologia dos adenocarcinomas cutâneos em canídeos

Abstract

CONTRIBUTION FOR THE STUDY OF THE BIOPATHOLOGY OF CANINE CUTANEOUS ADENOCARCINOMAS Ana Laura da Silva Santos Saraiva Mestrado em Medicina e Oncologia Molecular ABSTRACT The cutaneous adenocarcinomas are included in the wide group of the epithelial tumours with adnexal differentiation which, although relatively rare in dogs, are of importance in veterinary pathology. Some authors suggest that the small incidence of the cutaneous adenocarcinomas is due to their non- or misdiagnosis. Therefore, a more precise characterization of these tumours will be of help for a better diagnostic of these lesions. We analysed 31 malignant tumours with glandular differentiation, in dogs: 8 apocrine malignant tumours, 6 ceruminous malignant tumours, 7 sebaceous carcinomas and 10 hepatoid gland carcinomas. In our study sample, and whenever possible, we analysed several clinical parameters, namely the sex, age and breed of the animals, and size, position and evolution of the lesions. We also used histochemistry and immuno-histochemestry (cytokeratins AE1/AE3 and 14, vimentin, p63, calponin and Ki-67) to further characterize the tumours under study. Our results showed that the incidence of the studied tumours did not relate to the breed, was higher in older animals (8-12 years) and affected males more than females. The clinical evolution of the lesions was normally favourable as no distant metastases were observed, even when vascular invasion was present. Also, local recurrence was rare. Our histopathological analysis revealed that these tumours had a tendency for epidermis invasion, ulceration, necrosis and mononuclear inflammatory infiltration. By immuno-histochemistry we showed that CK14, p63 and calponin can be used as molecular markers for the diagnosis and characterization of the cutaneous adenocarcinomas. We determined the proliferation index of the various tumours using a specific antibody anti-Ki-67 and showed that this is indeed an accurate technique that can be used in future to further characterize the biological behaviour of the cutaneous glandular carcinomas.