Predictors of Clinical Outcome in Primary Progressive and Relapsed Wilms Tumor in a Resource-Limited Setting

This study aims to evaluate survival outcomes and identify prognostic factors associated with relapse or treatment-refractory primary progressive Wilms tumor in a resource-limited South Asian setting.

This is a retrospective cohort study conducted at a single tertiary-care pediatric oncology center in Pakistan.

Clinical charts of patients aged under 18 years were retrospectively examined and included. Patients who had been diagnosed with relapsed or treatment-refractory primary progressive Wilms tumor during the period between January 2010 and December 2023 were included in the study. The occurrence of disease following full remission after usual therapy was termed relapse, whereas the absence of radiologic or symptomatic response to the first chemotherapy was termed primary progressive disease. The Kaplan-Meier was used to estimate overall survival and event-free survival.

Among 452 children treated for Wilms tumor, 58 (13%) developed relapse or disease progression. Five-year overall survival was 43% (95% confidence interval: 29-57%). Event-free survival (survival without relapse, progression, death, or abandonment) fell to 28% at one year and 20% at two years. At the time of diagnosis, stage 4 disease had a worse survival rate than stage 3 (24% vs 49%).

Presentation at an advanced stage of the disease and the inability to achieve first remission are strong predictors of poor survival.