Abstract
Upper tract urothelial carcinoma (UTUC) is a relatively rare malignant neoplasm of the urinary system. Due to its highly aggressiveness, the tumor has already undergone invasive growth when most UTUC patients are diagnosed. In addition, the most common cause of fever in cancer patients is infection, and cancer patients with neoplastic fever are relatively rare. We reported a 58-year-old man with invasive high-grade UTUC accompanied by hyperthermia.