Abstract
Background. The most common renal tumors in adults is renal cell carcinoma. Wilms, tumor in subjects older than 16 years is rare; only 3% of Wilms, tumors are reported in adults, which explain the difficulties in diagnosis and treatment of this tumor entity in this age group.
METHODS. Patient with stage IV adult nephroblastoma with favorable histology was described, current treatment modalities were discussed, and the literature was reviewed.
Results. Ninteen year old female patient is presented with renal mass, abdominal lymphadenopathy, and bilateral pulmonary deposits. Sonar guided biopsy from the renal mass was taken and pathology revealed nephroblastoma. Right nephrectomy was performed and the pathological examination revealed classic histology of nephroblastoma. The case diagnosed as stage IV adult Wilms, tumor with favorable histology. According to National Wilms, Tumor Study Group (NWTS-3), multimodal therapy was initiated immediately after surgery. The patient failed to respond to the first line therapy and died due to disease progression.
conclusion. Adult Wilms, tumor has no specific guidelines and this may lead to improper or incorrect treatment.

