Prevention of treatment abandonment remains an important challenge to increase survival of Wilms tumor in sub-Saharan Africa: A report from Wilms Africa-CANCaRe Africa

Background: The Wilms Africa studies implemented an adapted Wilm's tumor (WT) treatment protocol in sub-Saharan Africa in two phases. Phase I began with four sites and provided out-of-pocket costs. Phase II expanded the number of sites, but lost funding provision. Objective is to describe the outcomes of Phase II and compare with Phase I. Methods: Wilms Africa Phase I (n = 4 sites; 2014-2018) and Phase II (n = 8 sites; 2021-2022) used adapted treatment protocols. Funding for families' out-of-pocket costs was provided during Phase I but not Phase II. Eligibility criteria were age less than 16 years and newly diagnosed unilateral WT. We documented patients' outcome at the end of planned first-line treatment categorized as treatment abandonment, death during treatment, and disease-related events (death before treatment, persistent disease, relapse, or progressive disease). Sensitivity analysis compared outcomes in the same four sites. Results: We included 431 patients in Phase I (n = 201) and Phase II (n = 230). The proportion alive without evidence of disease decreased from 69% in Phase I to 54% in Phase II at all sites (p = .002) and 58% at the original four sites (p = .04). Treatment abandonment increased overall from 12% to 26% (p < .001), and was 20% (p = .04) at the original four sites. Disease-related events (5% vs. 6% vs. 6%) and deaths during treatment (14% vs. 14% vs. 17%) were similar. Conclusion: Provision of out-of-pocket costs was important to improve patient outcomes at the end of planned first-line treatment in WT. Prevention of treatment abandonment remains an important challenge.