Xp11.2 translocation renal cell carcinoma with TFE3 gene fusion in the elderly: case report and literature review.

A 68-year-old man was followed up with chronic kidney disease. Follow-up CT incidentally detected a tumor at the left kidney and multiple small nodular shadows in the lungs bilaterally. The patient underwent needle biopsy and was diagnosed with Xp11.2 translocation renal cell carcinoma (RCC) pathologically. Hence, laparoscopic nephrectomy was performed. Fluorescence in situ hybridization analysis revealed a break-apart of the transcription factor E3 (TFE3) genes in the left tumor. After 2 months postoperatively, nivolumab and ipilimumab were administered thrice intravenously, considering the intermediate risk by the IMDC risk classification. However, pleural effusion occurred but was removed adequately. Lung metastasis decreased, but new metastasis occurred at the left iliopsoas muscle. Target therapy was performed with axitinib. Unfortunately, he died 6 months later postoperatively. These tumors commonly occur in children than in adults, and very rare in elderly patients. Xp11.2 translocation RCC in the elderly has a poorer prognosis than that in children. To date, no effective treatment for Xp11.2 translocation RCC has been established.