Primeiro registro de tumor de células de Sticker em Canis lupus familiaris de Portel, Pará

Transmissible Venereal Tumor (TVT) is a contagious neoplasm of allogeneic origin, transmitted mainly through sexual intercourse, but also through licking or direct contact with viable tumor cells, and can manifest in extragenital sites. The occurrence of TVT in the oral cavity is uncommon, representing approximately 3 to 3.5% of reported cases, and requires attention in the differential diagnosis of oral masses in dogs. This paper describes the case of a rescued mixed-breed female dog treated in the municipality of Porte, Pará, presenting with a friable mass in the hard and soft palate, associated with dyspnea, oral and nasal discharge, progressive weight loss, and submandibular lymphadenomegaly. Cytology obtained by fine-needle aspiration revealed a population of large round cells with vacuolated cytoplasm and oval nuclei, consistent with TVT. Despite the clinical support provided, the patient experienced rapid deterioration and died before the start of chemotherapy with vincristine sulfate, the standard treatment for the disease. This case reinforces the importance of fine-needle aspiration biopsy (FNAB) as a diagnostic tool in oral lesions of uncertain etiology, especially in regions with limited laboratory resources, and highlights the epidemiological relevance of recording extragenital forms of transvaginal tumor (TVT). Therefore, the inclusion of TVT in the differential diagnosis of oral masses and early diagnosis are essential for the proper clinical management and prognosis of patients.