Metastatic Extraosseous Ewing's Sarcoma (EES)/Primitive Neuroectodermal Tumor (PNET) of the Kidney: 8-Year Durable Response After Induction and Maintenance Chemotherapy

Abstract

Clinical Practice Points •Extraosseous Ewing's sarcomas (EES)/primitive neuroectodermal tumors (PNET) of the kidney are rare. •They are classified within the Ewing's sarcoma family of tumors (ESFT) and include those arising from the kidney. •We report a patient who presented with metastatic EES/PNET of the kidney, was treated with chemotherapy without local therapy, and achieved a durable clinical remission that has lasted longer than 8 years. •This case report illustrates the importance of obtaining a biopsy of a kidney tumor that appears atypical for renal cell cancer and promptly initiating upfront combination chemotherapy, if the diagnosis of EES/PNET is confirmed. •The role of cytoreductive nephrectomy (CN) is not defined in this patient population. •We believe that long-term disease-free survival can be achieved with chemotherapy alone. •CN may not be necessary in the management of patients with metastatic EES/PNET of the kidney, and may limit the ability to administer intensive chemotherapy regimens such as high-dose ifosfamide. •Extraosseous Ewing's sarcomas (EES)/primitive neuroectodermal tumors (PNET) of the kidney are rare. •They are classified within the Ewing's sarcoma family of tumors (ESFT) and include those arising from the kidney. •We report a patient who presented with metastatic EES/PNET of the kidney, was treated with chemotherapy without local therapy, and achieved a durable clinical remission that has lasted longer than 8 years. •This case report illustrates the importance of obtaining a biopsy of a kidney tumor that appears atypical for renal cell cancer and promptly initiating upfront combination chemotherapy, if the diagnosis of EES/PNET is confirmed. •The role of cytoreductive nephrectomy (CN) is not defined in this patient population. •We believe that long-term disease-free survival can be achieved with chemotherapy alone. •CN may not be necessary in the management of patients with metastatic EES/PNET of the kidney, and may limit the ability to administer intensive chemotherapy regimens such as high-dose ifosfamide.