Metastatic apocrine gland adenocarcinoma in a dog

Abstract

The apocrine gland adenocarcinoma is rarely reported in dogs, common in dogs and having no sex predisposition. They usually present a single lump reaching up 10 cm in diameter. In dogs, the thoracic and pelvic limbs are the common sites. Generally, the apocrine gland neoplasms have a benign behavior; metastasis can occur through lymphatic and blood dissemination when they are malignant. We report the case of a 16-year-old, uncastrated, male Poodle dog. The client reported a lesion in the right ear that had purulent and bloody discharge for 30 days, however, on physical examination, a small mass was observed in the right thoracic limb together with a reactive right subscapular lymph node. Samples were collected from both sites for cytological examination, which had an inconclusive result. Nodulectomy was performed on the right thoracic limb, subscapular lyphadenectomy and auricular nodulectomy. The histopathological analysis revealed an apocrine gland adenocarcinoma in the thoracic limb with metastasis to the cervical lymph node and sebaceous epithelioma in the auricular lesion. The client refused the chemotherapy protocol proposed and, the patient died 30 days after the surgical procedure.