Augmentation of Therapy for Combined Loss of Heterozygosity 1p and 16q in Favorable Histology Wilms Tumor: A Children’s Oncology Group AREN0532 and AREN0533 Study Report

Dix DB, Fernandez CV, Chi YY, Mullen EA, Geller JI, Gratias EJ, Khanna G, Kalapurakal JA, Perlman EJ, Seibel NL, Ehrlich PF, Malogolowkin M, Anderson J, Gastier-Foster J, Shamberger RC, Kim Y, Grundy PE, Dome JS; AREN0532 and AREN0533 study committees. Augmentation of Therapy for Combined Loss of Heterozygosity 1p and 16q in Favorable Histology Wilms Tumor: A Children’s Oncology Group AREN0532 and AREN0533 Study Report. J Clin Oncol. 2019 Oct 20;37(30):2769-2777. doi: 10.1200/JCO.18.01972. Epub 2019 Aug 26. PMID: 31449468; PMCID: PMC7001789.

In National Wilms Tumor Study 5 (NWTS-5), tumor-specific combined loss of heterozygosity of chromosomes 1p and 16q (LOH1p/16q) was associated with adverse outcomes in patients with favorable histology Wilms tumor. The AREN0533/AREN0532 studies assessed whether augmenting therapy improved event-free survival (EFS) for these patients. Patients with stage I/II disease received regimen DD4A (vincristine, dactinomycin and doxorubicin) but no radiation therapy. Patients with stage III/IV disease received regimen M (vincristine, dactinomycin, and doxorubicin alternating with cyclophosphamide and etoposide) and radiation therapy. Patients were enrolled through the AREN03B2 Biology study between October 2006 and October 2013; all underwent central review of pathology, surgical reports, and imaging. Tumors were evaluated for LOH1p/16q by microsatellite testing. EFS and overall survival were compared using the log-rank test between NWTS-5 and current studies.