Imaging Findings of Renal Cell Carcinoma Associated with Xp11.2 Translocation/TFE3 Gene Fusion in a 4-Year-Old Male: Case Report and Review of Literature

Abstract

We represent a pathologically proven case of a four-year-old male patient with renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion, which is rare but more frequent in children or young adults. Computed tomography showed about 2.5 cm size ill-defined mass in the right kidney. The mass was hyperechoic on ultrasound. Magnetic resonance imaging demonstrated a mass with capsular enhancement and diffusion restriction. We present a case of Xp11.2 renal cell carcinoma and provide review of the literature. Index words : Renal cell carcinoma•Xp11.2 translocation•TFE3 gene fusion•Diffusion-weighted MRI•ChildWhile Wilms' tumor accounts for 87% of all pediatric renal masses, pediatric renal cell carcinoma (RCC) is rare. RCC in children or young adults is often hereditary and is associated with von Hippel-Lindau syndrome. Sporadic RCC in children or young adults is less common and is often associated with Xp11.2 translocation/TFE3 gene fusion. The proportion of Xp11.2 translocation/TFE3 gene fusion RCC (Xp11.2 RCC) among RCC in young age group varies from 20% to 70%. Although several studies about pathologic features of Xp11.2 RCC have been reported (1), its radiological imaging findings are not yet fully understood. We report a case of a pediatric Xp11.2 RCC, emphasizing the radiological aspects, including ultrasound (US), computed tomography (CT), and magnetic resonance (MR) imaging with diffusion-weighted imaging (DWI) and dynamic enhancement.