A retrospective study of primitive neuroectodermal tumor (PNET) of the kidney in a tertiary cancer center in India.

Abstract

361 Background: Primitive neuroectodermal tumours (PNET) of the kidney are rare tumours with aggressive behaviour. This study was conducted to review the diagnosis and management of patients with renal PNET at our centre. Methods: This was a retrospective study conducted at a tertiary cancer care centre in Mumbai, India. The demographic and clinical data of 17 patients treated by the uro-oncology services were retrieved from electronic medical records. Descriptive analysis was performed for baseline characteristics.Overall & progression-free survival was determined using the Kaplan Meier method. Cox regression was used for multivariate analysis. Results: There were 12 male and 5 female patients in this cohort with a median age of 27 years. At diagnosis 2 patients had metastatic disease and 15 patients had non-metastatic disease. Median follow up in this cohort was 22 months (range 2-30 months). Presenting complaints were hematuria, abdominal pain, flank pain, fever, bone pain, and incidentally detected renal mass. All patients were Mic -2 positive and 13 were FLI-1 positive on immunohistochemistry. Fourteen patients underwent radical nephrectomy. One (5.9%) patient received both neoadjuvant and adjuvant chemotherapy, 8 (47.1%) received adjuvant and 2 (11.8%) received palliative chemotherapy upfront. Eight patients received adjuvant radiation to the renal bed.There was disease progression in12 patients,10 of 15 patients with non metastatic disease at diagnosis eventually developed metastasis.The median progression free survival (PFS) was 10.55 months.The pathological feature that was associated with a shorter PFS was tumor size ⩾10 cm(p = 0.044).The median overall survival was 20.04 months (95% CI 9.49 -not reached). The presence of metastasis and treatment received significantly impacted overall survival (OS). Median OS in patients with non-metastatic disease was not reached versus 14.1 months in those with metastatic disease (p = .019).The median OS in patients treated with multimodality approach was 20.11 months. Patients did not undergo surgery had a median OS of 5.45 months (p < .001) and those who did not receive any chemotherapy had a median OS of 4.57 months (p = .024).Thus, patients who received multimodality treatment had better outcomes. Conclusions: PNET kidney is an aggressive tumor which should be treated with a multimodality approach. Tumor size ⩾10 cm was an adverse prognostic factor.