Primitive neuroectodermal tumor of the kidney: a single-institute series of six patients from China

Primary primitive neuroectodermal tumour of the kidney in adults: Experience of managing 12 cases with systematic review and pooled analysis of literature

INTRODUCTION

Primitive neuroectodermal tumor (PNET) of the kidney is unusual in adults. These tumours are diagnosed mainly on histopathology and that too sometimes has limitations. With this study, we aimed to review our clinical and histopathological data of patients with renal PNET and reviewing the world literature.

METHODS

In this retrospective study, we reviewed our database from January 2006 to July 2018 to include all the cases of primary PNET of the kidney. We also performed systematic literature search to identify all the relevant series on renal PNET.

RESULTS

A total of 12 patients including 5 men and 7 women were managed during the above mentioned period. Out of these 7 patients, 2 patients had metastasis at diagnosis, one had locally advanced disease, 6 underwent radical nephrectomy, 5 patients received adjuvant chemotherapy (two currently receiving) and only 1 patient received adjuvant radiotherapy (RT). On Immunohistochemistry (IHC), CD99 and FLI1 were positive in all the patients. Median survival was 10 months. In our review 10 studies were included, 38.6% of the patients had metastatic disease and 10.7% had locally advanced disease at diagnosis. Overall mean survival was 33.75 months. CD99 and FLI1 were positive in 94.3% and 78.5%, respectively.

CONCLUSION

PNET remains a pathological diagnosis and IHC has important place in diagnosis of PNET. Locally advanced and metastatic disease is common at diagnosis leading to overall poor survival.

Primary Ewing sarcoma of the kidney: a case report and treatment review

Ewing sarcomas/primitive neuroectodermal tumors (ES/PNET) of the kidney are rarely found high-grade malignant tumors, offering poor prognosis. Although established treatment guidelines for ES of kidney are scarce, a multi-modality treatment approached is typically implemented. Herein, we report a 14-year-old female patient with ES of right kidney. Post-nephrectomy disease recurrence was treated with chemotherapy (i.e., vincristine, doxorubicin and cyclophosphamide); marked reduction in tumor size (i.e., from 18.5 × 11.3 cm² to 3.7 × 2.2 cm²; ~96% reduction in size) as per computed tomography images was observed. We present our treatment experience and review from the available literature.

Peripheral primitive neuroectodermal tumor: dynamic CT, MRI and clinicopathological characteristics--analysis of 36 cases and review of the literature

Background

The peripheral primitive neuroectodermal tumor (pPNET) is a rare malignant tumor originating from neuroectoderm. The accurate diagnosis is essential for the treatment of pPNET.

Methods

we performed the largest cases of retrospective analysis thus far to review the unique computed tomography (CT), magnetic resonance imaging (MRI), and clinicopathological features of pPNET. The tumor location, morphological features, signal intensity, contrast enhancement characteristics, and involvement of local soft tissues of 36 pPNETs were assessed.

Results

Our results showed that there were more men (25/36) than women pPNETs patients. Unenhanced MRI (16 cases) showed that 14 cases were isointense and 2 cases were hypointense on T1WI. Nine cases were isointense and 7 were hyperintense on T2WI. Most pPNETs had heterogeneous signal intensity with small necrosis (CT: 31/36; MRI: 14/16) as well as heterogeneous enhancement (CT: 34/30; MRI: 15/16). The tumors usually had ill-defined borders and irregular shapes (CT: 30/36; MRI: 15/16). Pathologic exam showed small areas of necrosis in all tumors.

Conclusions

The diagnosis of pPNET should be suggested in young men when the imaging depicts a single large ill-defined solid mass with small area of necrosis, especially for those whose images show iso-intense on T1WI and T2WI and have heterogeneous enhancement.

Open removal of a retained retrohepatic inferior vena cava filter with a residual primary neuroectodermal renal tumoral thrombus

Primary neuroectodermal renal tumours (PNET) are rare and aggressive neoplasms; thrombosis of the inferior vena cava (IVC) is associated with this entity. We report here the case of a 19-year-old man who experienced a new onset of abdominal pain. A CT scan revealed a large left renal mass, perirenal haematoma and IVC thrombosis. Owing to an acute drop in haemoglobin and subsegmentary pulmonary embolism, he underwent emergency selective renal artery angiography and embolisation of bleeding vessels and IVC filter (IVCF) placement. Once stable, he underwent a left radical nephrectomy and IVC thrombectomy; the pathology report confirmed PNET. 6 months later, imaging revealed a residual tumoral thrombus in the IVCF located in the retrohepatic IVC. The patient underwent removal of this device and the thrombus via a right thoracoabdominal approach. He recovered well and at 4 months, he continues his chemotherapy cycles.