Retroperitoneal Ewing's sarcoma

Primitive neuroectodermal tumour (PNET) of the kidney: a rare renal tumour in adolescents with seemingly characteristic radiological features

BACKGROUND

Primitive neuroectodermal tumours (PNETs) constitute a family of neoplasms of presumed neuroectodermal origin that predominantly present as bone or soft-tissue masses in adolescents and young adults. PNET arising in the kidney is rare.

OBJECTIVE

To describe the radiological features in three patients with primary renal PNET.

MATERIALS AND METHODS

The radiological features of primary renal PNET in three adolescent patients (age 10, 14 and 16 years) are described.

RESULTS

Tumour thrombus extending into the renal vein and inferior vena cava was noted in all three patients. In addition, further tumour extension into the atrium was seen in two patients with extension into a pulmonary artery in one patient. Neural foraminal and intraspinal extension close to the origin of the tumour was identified in two patients. Liver, bone and lung metastases were identified.

CONCLUSION

While rare, one should consider the diagnosis of PNET when encountering a renal mass with aggressive features such as inferior vena cava tumour thrombus, direct intraspinal invasion and distant metastasis.

Ewing's sarcoma/primitive neuroectodermal tumor of the ureter: a case report and review of the literature

Extraosseous Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is a rare soft tissue tumor of childhood usually found in the extremities. The authors present the case of a 17-year-old girl who presented with right flank pain and hematuria and during operation was found to have a right ureteral mass. The histopathologic, immunohistochemical, ultrastructural, and cytogenetic characteristics of the excised mass were consistent with extraosseous ES/PNET. This is the first known reported case of extraosseous ES/ PNET of the ureter. The pathologic features and clinical management of this case, as well as a review of the literature, are presented.