RADIOTHERAPY OMITTED IN THE TREATMENT OF SELECTED CHILDREN UNDER 3 YEARS OF AGE WITH STAGE-III FAVORABLE HISTOLOGY WILMS-TUMOR

Background. Current treatment of stage III favorable histology (FH) Wi lms tumor is surgery, radiotherapy to residual disease, and ''triple'' chemotherapy (vincristine, dactinomycin, and doxorubicin) for 12 mont hs. This study tests the hypothesis that some stage III patients, espe cially very young children with minimal residual abdominal disease, mi ght be successfully treated without radiotherapy, thereby avoiding the adverse late effects associated with radiotherapy. Procedure. From 19 84, radiotherapy was omitted from the treatment of 8 carefully selecte d children who were younger than 3 years of age at diagnosis with stag e III Wilms tumor by virtue of microscopic residual disease after surg ery and whose lymph nodes were not involved by tumor. They were follow ed with bimonthly abdominal ultrasound examinations to assess local co ntrol. Results. Follow-up is now from 2 to 12 years (me dian 6 years) and 7 of the 8 children are alive and well with no abdominal recurrenc e. One child relapsed in the lungs and despite further treatment died of progressive disease. The disease-free survival (DFS) and overall su rvival (OS) are therefore both 87.5%. Conclusions. The DFS and OS in t his admittedly small sample are consistent with the survival rates for stage III FH Wilms tumor in the first United Kingdom Children's Cance r Study Group (UKCCSG), North American (NWTS), and European (SIOP) Wil ms Tumor studies. Larger numbers of patients are needed to determine w hether or not this treatment approach is generally applicable, but we conclude that some children in this stage III ''substage'' may be trea ted successfully without radiotherapy. Med. Pediatr. Oncol. 31:150-152 , 1998. (C) 1998 Wiley-Liss, Inc.