[Current features of malignant renal tumors in children]

The diagnosis of nephroblastoma is based on a postulate: any solid intrarenal tumour in a child between the ages of six months and six years is a nephroblastoma and therefore requires preoperative chemotherapy. Fine needle biopsy to obtain histological confirmation is only justified in doubtful cases. The prognosis is dominated by unfavourable, sarcomatous and anaplastic histological forms, which represent less than 10% of all nephroblastomas and are responsible for one half of deaths. Due to the better understanding of the therapeutic sequelae, particularly following radiotherapy, this modality is avoided whenever possible in young children. Radiotherapy is only indicated in stage II, with lymph node invasion, and stage III forms with favourable histology. It is indicated in all forms with unfavourable histology except for stage I anaplastic tumours. Surgery is indicated for metastases, especially lung metastases, once again to avoid irradiation. Lastly, bilateral partial nephrectomy is the best treatment for bilateral nephroblastoma.