Nefroureterectomia como abordagem terapêutica ao carcinoma de células renais em cão: relato de caso

Abstract

Malignant neoplasms are one of the leading causes of mortality in companion animals. Among the primary renal neoformations in dogs, renal cell carcinoma (RCC) stands out as the most commonly diagnosed malignant tumor in veterinary clinical routine. This condition is highly metastatic and predominantly manifests in middle-aged male dogs, with no specific breed predilection. Diagnosis is made through clinical signs and the performance of complementary tests. Among these tests, ultrasonography is the most specific method for checking the renal mass, and histopathological analysis is the gold standard for confirming renal carcinoma. Nephroureterectomy is the crucial therapeutic intervention in the treatment of RCC in canines. The present work aims to detail the surgical technique used, as well as highlight the pathological aspects of the disease based on the case report of a six-year-old male mixed breed dog, attended at the Veterinary Hospital of the Federal University of Paraíba (HV/UFPB) in Areia-PB. The main complaint during the anamnesis were progressive clinical signs of reduced appetite, vomiting, and cachexia. Hematological and biochemical tests were not sufficient to clarify the case, since the animal only presented monocytosis and decreased serum levels of urea and creatinine. Urinalysis showed blood and proteins in the urine highlighting the involvement of the urinary tract, and ultrasonography revealed the presence of a heterogeneous left renal mass with areas responsive to Doppler. The animal was referred for exploratory laparotomy to better visualize the adjacent tissues involved. In this case, a left nephroureterectomy was chosen, during which adhesions in intestinal loops, omentum, caudal vena cava, and abdominal aorta were found, making the surgery even more challenging. Histopathological analysis confirmed the diagnosis of renal cell carcinoma. After surgical treatment, the animal had a good recovery with improvement in body score. However, about five months later, he presented with lameness and pain in the right thoracic limb, suggesting possible metastases of RCC. Further tests confirmed the presence of an intra-abdominal mass in the left hypogastric region and suggested the presence of neoplastic infiltration in the right humerus. Despite efforts to control clinical signs, the patient showed progressive worsening and, ultimately, was euthanized due to the unfavorable prognosis.