Synchronous Ipsilateral Occurrence of Advanced Renal Pelvic Urothelial Carcinoma With Lung Metastasis and Localized Renal Cell Carcinoma: A Case Report.

The patient was a 92-year-old woman who presented with a complaint of difficulty in urination. Her abdominal computed tomography (CT) revealed two distinct types of tumors in the lower and upper poles of the right kidney, and chest CT revealed multiple lung metastatic tumors. A laparoscopic right radical nephrectomy was performed, and the lower pole tumor was diagnosed as clear cell renal cell carcinoma (RCC), whereas the upper pole tumor was renal pelvic urothelial carcinoma (UC). The lung tumor was diagnosed as metastatic UC via CT-guided biopsy. In this case, histological examination of the primary tumor site resection and immunohistochemical examination of the lung metastases were important in diagnosing metastatic UC. Despite the challenges associated with synchronous RCC and upper tract UC (UTUC), appropriate treatment strategies, including surgical intervention and systemic chemotherapy, may improve prognosis and prolong survival. The findings contribute to the limited knowledge on synchronous RCC and UTUC, offering valuable insights to help clinicians enhance decision-making and improve patient care in similar scenarios.