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.