The incidence of adult Wilms' tumor is difficult to determine but the lesion is rare. The prognosis is poorer than in children, but in adults is often diagnosed at a higher clinical stage and with an unfavorable histologic type. There may be other reasons for the poor prognosis as well. A 33-year-old woman with metastatic disease (bilateral kidney tumors, pulmonary and multiples lymph nodes metastases) is described. Treatment with chemotherapy consisted of doxorubicin, ifosfamide and etoposide which resulted in complete remission that persisted for only three months. The factors that probably contributed to rapid progression included un favorable histology (predominant nodular blastematous elements which were anaplastic) and advanced disease. The precise histologic diagnosis was late precluding to plan the correct treatment.