RT Journal Article T1 Is radiotherapy required in first-line treatment of stage I diffuse anaplastic Wilms tumor? A report of SIOP-RTSG, AIEOP, JWiTS, and UKCCSG. A1 Davila-Fajardo, Raquel A1 van-den-Heuvel-Eibrink, Marry M A1 van-Tinteren, Harm A1 Spreafico, Filippo A1 Acha, Thomas A1 Bergeron, Christophe A1 de-Camargo, Beatriz A1 Oldenburger, Foppe A1 Rube, Christian A1 Oue, Takaharu A1 Vokuhl, Christian A1 de-Krijger, Ronald R A1 Vujanic, Gordan A1 Sebire, Neil A1 Coulomb-L'Hermine, Aurore A1 Collini, Paola A1 Gandola, Lorenza A1 Pritchard-Jones, Kathy A1 Graf, Norbert A1 Janssens, Geert O A1 van-Grotel, Martine K1 Wilms tumor K1 Diffuse anaplasia K1 Radiotherapy K1 Stage I AB As a significant proportion of relapses occurred in the tumor bed or abdomen on patients with the fifth National Wilms Tumor Study stage I anaplastic Wilms tumor (WT), flank radiotherapy was added for stage I anaplastic WT in the subsequent study of the Children's Oncology Group (AREN0321). Preliminary results revealed reduction of relapse rate and improved survival. In cases treated with preoperative chemotherapy, such as in International Society of Pediatric Oncology (SIOP), the value of radiotherapy has never been studied. The aim of this observational study is to describe the pattern of recurrence and survival of patients with stage I diffuse anaplastic WT (DAWT) after induction chemotherapy. Retrospective data analysis of the pattern of relapse and survival of all patients with stage I DAWT were included in recent SIOP, L'Associazone Italiana Ematologica Oncologia Pediatrica (AIEOP), Japan Wilms Tumor Study Group (JWiTS), United Kingdom Children's Cancer Study Group (UKCCSG) renal tumor registries. Postoperative treatment consisted of actinomycin D, vincristine, and doxorubicin for 28 weeks without local irradiation. One hundred nine cases with stage I DAWT were identified, of which 95 cases received preoperative chemotherapy. Of these, seven patients underwent preoperative true-cut biopsy. Sixteen of the 95 patients relapsed (17%), six locally, four at distant site, and six combined, and all treated according to SIOP 2001 relapse protocol, which resulted in a 5-year overall survival of 93%. Despite 13% locoregional relapse rate, an excellent rescue rate was achieved after salvage treatment, in patients with stage I DAWT whose first-line treatment comprised three-drug chemotherapy (including doxorubicin), without flank irradiation. Therefore, we continue not to advocate the use of radiotherapy in first-line treatment after preoperative chemotherapy in stage I DAWT in the next SIOP protocol. PB Wiley Periodicals YR 2019 FD 2019-12-19 LK http://hdl.handle.net/10668/14933 UL http://hdl.handle.net/10668/14933 LA en NO Fajardo RD, van den Heuvel-Eibrink MM, van Tinteren H, Spreafico F, Acha T, Bergeron C, et al. Is radiotherapy required in first-line treatment of stage I diffuse anaplastic Wilms tumor? A report of SIOP-RTSG, AIEOP, JWiTS, and UKCCSG. Pediatr Blood Cancer. 2020 Feb;67(2):e28039 DS RISalud RD Apr 19, 2025