[A CASE REPORT OF Xp11.2 TRANSLOCATION RENAL CELL CARTINOMA SUSPECTED RENAL PELVIC CARCINOMA].

The patient was a 33-year-old female who visited the Department of Gastroenterology of this hospital after experiencing lower abdominal pain and nausea. The patient was referred to this department after suspicions of right kidney hemorrhage revealed by non-contrast computed tomography (CT). We also identified hematuria macroscopically, and contrast-enhanced CT scans revealed uneven deep staining in the upper right kidney during the early phase. Furthermore, by the late phase, we identified a 29-mm solid tumor with no staining. There was no clear pseudomembrane and no clear boundary with the kidney parenchyma. Additionally, there was no metastasis to the lymph nodes and other organs. Based on the above findings, we suspected renal parenchymal infiltration of right renal cell carcinoma (RCC) or right renal pelvic carcinoma. Since the patient was young, we considered the risk of the residual tumor and performed total nephroureterectomy and lymph node dissection with an enlarged view. The inside of the resected tumor specimen showed significant necrosis and hematoma spread, which had infiltrated the renal pelvis. Based on the characteristic histological findings and genetic results obtained using the fluorescence in situ hybridization (FISH) approach, we diagnosed the patient with Xp11.2 translocation RCC. No additional treatments were provided after surgery, and even now the patient is being followed-up through outpatient visits, but there has been no recurrence or new metastasis. There have only been a few reported cases of Xp11.2 translocation RCC; therefore, in many cases, treatments and follow-up duration according to the disease stage and disease prognosis have not been determined. In this study, we report a case of Xp11.2 translocation RCC experienced at our hospital, with additional literature considerations.