Fibrossarcoma em região cervical em cão da raça spitz alemão: relato de caso

Abstract

Neoplasms occur due to several alterations in the cellular genome, and can be inherited or acquired throughout life, as a result of internal processes of the organism or exposure to various environmental factors. Fibrosarcoma is a malignant tumor of mesenchymal origin that develops from fibroblasts. In dogs, this neoplasia is less common, corresponding to approximately 1.5% of tumors that affect the skin and subcutaneous tissue. It is more common in large breeds, especially in golden retrievers, Dobermans and Rottweilers. The objective of this study is to report a case of fibrosarcoma located in the cervical region of a dog, of the German spitz breed, treated at the Veterinary University Hospital of the Federal University of Paraíba, Areia campus - PB. An increase in volume was presented on the left side of the neck as a result of a non-ulcerated, firm, rounded, intact and adherent cervical mass. The treatment of choice was surgical removal of the mass, and the animal was referred to the Small Animal Surgery Center of HUV-UFPB. Microscopic examination of the fragments revealed the presence of neoplastic cells (moderately differentiated fibroblasts) replacing the superficial and deep dermis, with a diagnosis of grade 2 fibrosarcoma. In the last 30 days after surgical resection, a new tumor grew rapidly in the region and the patient died. In conclusion, the study highlights the importance of early diagnosis and appropriate treatment in cases of neoplasia in dogs, with emphasis on fibrosarcoma, a neoformation that is uncommon in this species and, specifically, in the breed addressed in this case report. The cervical location of the neoplasia, together with post-surgical tumor recurrence, was associated with an unfavorable prognosis, due to the specificities of specific organs, such as the trachea and esophagus, in addition to the involvement of important vasculoneural structures.