Renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusions: clinical experience and literature review

Abstract

Aim: To analyze the clinicopathological features of renal cell carcinoma (RCC) associated with Xp11.2 translocation/TFE3 gene fusions (Xp11.2 RCC) in our institution. Materials & methods: We screened 983 RCC specimens. TFE3 immunohistochemical staining and FISH assay confirmed 22 Xp11.2 RCCs out of 65 suspicious cases. Clinicopathological and treatment outcomes of 22 patients were retrospectively analyzed. Results: In total, 22 patients included 13 females and nine males with a mean age of 27 years. Ten patients showed gross hematuria. Treatments included surgeries, immunotherapy and molecular-targeted therapy. Seven cases were at stage III/IV and four cases had tumor thrombosis or distant metastasis. During a median follow-up of 34 months, 19 patients were alive while three died of distant metastasis. Conclusion: Xp11.2 RCC is rare and FISH proved a useful diagnostic tool. Surgical resection achieved favorable outcome for early disease. Adult patients at advanced stage had poorer outcomes even with postoperative adjuvant therapy.