Associations of Patient Age, Tumor Nephrectomy Weight, and Tumor Diameter with Event-Free and Overall Survival in Stage I or II Favorable Histology Wilms Tumor: A Pooled Analysis of Children’s Oncology Group Studies AREN0532 and AREN03B2

Renfro LA, Vallance KL, Tfirn IC, Evageliou N, Benedetti DJ, Shamberger RC, Ehrlich PF, Cost NG, Aldrink JH, Schechter A, Treece A, Parsons LN, Walz AL, Sutton KS, Armstrong AE, Fernandez CV, Dome JS, Geller JI, Mullen EA; AREN03B2 Authorship Group. Associations of Patient Age, Tumor Nephrectomy Weight, and Tumor Diameter with Event-Free and Overall Survival in Stage I or II Favorable Histology Wilms Tumor: A Pooled Analysis of Children’s Oncology Group Studies AREN0532 and AREN03B2. Ann Surg. 2025 Apr 11:10.1097/SLA.0000000000006726. doi: 10.1097/SLA.0000000000006726. Epub ahead of print. PMID: 40211953; PMCID: PMC12353671.

To evaluate age, TNW, or tumor diameter (TD) as continuous prognostic variables for outcomes in early stage FHWT after accounting for biology and treatment. Patient age (< 2 vs. ≥ 2 years) and tumor nephrectomy weight (TNW; < 550g vs. ≥ 550 grams) have been used to risk stratify children with stage I favorable histology Wilms tumor (FHWT) on Children's Oncology Group (COG) studies and select patients for omission of chemotherapy. Included patients had stage I or II FHWT per central review and were treated with nephrectomy only, EE4A, or DD4A on COG trials. Restricted cubic splines models were used to estimate the stage-specific effects of age, TNW, and TD on event-free survival (EFS) and overall survival (OS), accounting for treatment and biology.