Clear Cell Sarcoma of the Kidney: A Kidney Malignancy in an 8-Year-Old Female Patient

Clear cell sarcoma of the kidney (CCSK) is a rare pediatric renal malignancy, accounting for 5% of primary kidney cancers, often mistaken for the Wilms tumor due to similar presentation and imaging but differing in histology and prognosis. An 8-year-old female presented with a painless right flank mass without hematuria or constitutional symptoms. Ultrasound revealed a heterogeneous echo-complex mass (7.29 × 8.79 × 7.96 cm) in the right kidney's upper pole, with cystic and solid components. Contrast-enhanced CT urogram confirmed a hetero-enhancing mass (7.78 × 9.04 × 8.04 cm) with hydronephrosis and a claw sign, indicating renal origin. Radical nephrectomy and histopathology confirmed CCSK, with chemotherapy initiated. CCSK requires differentiation from the Wilms tumor for appropriate management. Early ultrasound and CT urogram are critical for identifying malignant features, guiding radical nephrectomy to improve outcomes.