[Secondary TFE3-associated renal cell carcinoma in a child treated for Ewing sarcoma]

Renal cell carcinoma is a rare pediatric malignant tumor of the kidney. Unlike Wilms tumor, the efficacy of chemotherapy and radiation therapy in pediatric renal cell carcinoma remains uncertain. Surgery is the best treatment and prognosis is favorable when the tumor is localized and completely eradicated. We report an exceptional observation in a 7-year-old girl with renal cell carcinoma who had been treated 20 months previously for Ewing sarcoma with chemotherapy and radiotherapy. The renal tumor was revealed by abdominal pain without hematuria. She underwent a radical nephrectomy, and histopathology concluded in renal carcinoma associated with translocation Xp 11.2 grade 3 of Furhrman pT3a N1. No adjuvant therapy was given. After 3 years of follow-up, there is no evidence of local or metastatic recurrence. This observation is significant given the very young age of this patient, the occurrence after Ewing sarcoma with a short disease-free interval. It seems that translocation renal cell carcinoma is associated with previous exposure to chemotherapy, particularly topoisomerase II inhibitors or alkylating agents.