<prompt> Most impoant prognostic factor of wilms tumour -HistopathologyPloidy of cellsAge 1 yrMutation, of clp gene  <response>: Ans. is a i.e., Histopathology o Anaplastic nuclear change is the only criterion of unourable histology in Wilms tumor and all Wilms tumor lacking this feature are designated as having ourable histology. o Anaplastic nuclear change reflects extreme polypoidy is usually apparent under low magnification. Anaplastic histology remains a critical determinant of adverse prognosis. Even anaplasia restricted to kidney confers an increased risk of recurrence death, underscoring the need for correctly identifying this histologic features. 