– Predominant stromal histology – Simultaneous presence of intralobar nephrogenic rests – WT1 mutations and LOH 11p15 associated with relapse – Germline mutations in Denys-Drash syndrome and WAGR syndrome – 90% of patients with Denys-Drash syndrome and 50% with WAGR syndrome develop WT. Here, WT1 is linked to Denys-Drash syndrome.