TREATMENT OF CHILDREN WITH CLEAR-CELL SARCOMA OF THE KIDNEY - A REPORT FROM THE NATIONAL WILMS-TUMOR STUDY-GROUP

Purpose: To evaluate the effect of the sequential addition of doxorubicin (DOX) and cyctophosphamide (CTX) to the combination of vincristine (VCR) and dactinomycin (AMD) on the relapse-free survival of children with clear-cell sarcoma of the kidney (CCSK). Patients amd Methods: We determined the 6-year relapse-free survival rate for patients with CCSK treated on National Wilms' Tumer Study (NWTS)-1, NWTS-2, or NWTS-3 with the combination of VCR and AMD, with or without DOX, and for patients treated on NWTS-3 with the combination of VCR, AMD, and DOX with (regimen J) or without (regimen DD-RT) CTX. Results: The 6-year relapse-free survival rate for the eight children with CCSK treated with VCR, AMD, and radiation therapy was 25.0%, compared with 63.5% for the 58 children treated with VCR, AMD, DOX, and radiation therapy (P = .09). The 6-year relapse-free survival rate for children with CCSK treated on regimen DD-RT was 64.6%, compared with 58.2% for those treated on regimen J (P = .79). Conclusion: We conclude chat the addition of DOX to the combination of VCR plus AMD appeared to improve the 6-year relapse-free survival rate of children with CCSK. The addition of CTX in the dose and schedule used in NWTS-3 did not improve the 6-year relapse-free survival rate of children with CCSK. Because 30% of relapses occurred more than 2 years after diagnosis, prolonged follow-up evaluation of patients with CCSK is necessary. (C) 1994 by American Society of Clinical Oncology.