BACKGROUND: Risk management in oncology is critical due to toxicity, narrow therapeutic windows, and strict dosing schedules. This study analyzed post-authorization studies from the HMA-EMA Real-World Data Catalogues evaluating the effectiveness of risk minimization measures (RMM) for oncology medicines. RESEARCH DESIGN AND METHODS: We reviewed all RMM effectiveness studies registered in the HMA-EMA RWD Catalogues until February 2024, focusing on medicines classified under ATC codes 'L' and 'V10' for oncological conditions. Data from protocols and reports were analyzed, including study design, population, objectives, RMM types, process and outcomes indicators and reported effectiveness. RESULTS: Out of 1,280 records, 21 studies met the inclusion criteria. Most studies (81%) were cross-sectional surveys, 57% targeted healthcare professionals, and 86% used primary data. Additional RMMs were evaluated in 81% of studies. Process indicators were assessed in nearly all studies, but only 5% included outcome indicators. Of the 15 studies with available results, 60% were deemed effective, 27% inconclusive, and 13% ineffective by the sponsors. CONCLUSIONS: Future studies should set success thresholds in advance, use a dual evidence approach to measure outcomes, and consider new methods to increase participant numbers. Feasibility assessments prior to conducting studies are essential for achieving meaningful objectives in oncology risk management.