Metastatic adenocarcinoma in the parotid gland in a horse - clinical and pathological findings.

This case report details the findings of a metastatic adenocarcinoma of the parotid gland, a rare neoplasm in horses with limited treatment options. A 12-year-old, Criollo breed, gelding was presented with an enlarged left parotid gland that had been previously treated for 6 months without response to treatment. Based on the results of the diagnostic procedures performed, the horse underwent a total sialadenectomy and died of hypovolemic shock in the recovery room. Post-mortem examination revealed metastatic neoplastic infiltration of the submandibular lymph nodes and the lymphatic network at the entrance to the thorax. This case highlights the aggressive nature and poor prognosis of metastatic adenocarcinoma of the parotid gland in horses, underscoring the need for early diagnosis and the exploration of more effective therapeutic strategies.