Evaluation of adverse drug reactions in cancer-related settings using diverse real-world data.

The evaluation of adverse drug reactions in cancer-related settings represents a complex clinical challenge that extends beyond the toxicities associated with anticancer therapies, including drug-induced malignancies and treatment-related complications, in heterogeneous patient populations. Since randomized controlled trials are conducted in highly selected populations, their findings are not always directly generalizable to routine clinical practice. In this context, real-world data (RWD) have become an important resource for evaluating drug safety and clinical outcomes in real-world clinical practice. This review provides an overview of RWD-based approaches for evaluating adverse drug reactions in cancer-related settings, with a particular focus on how different data sources can be used to address clinically relevant safety questions. Electronic medical records enable the detailed evaluation of patient-level clinical information and have been used to identify clinical and pharmacokinetic factors associated with adverse drug reactions. Spontaneous adverse event reporting databases are particularly useful for detecting rare and unexpected adverse events, including drug-induced malignancies. Medical claims databases enable large-scale longitudinal analyses and evaluation of the incidence and time-to-onset of adverse drug reactions. Additionally, the Diagnosis Procedure Combination database provides detailed inpatient information and has been used to evaluate treatment-related complications in routine clinical practice. As each type of RWD has distinct strengths and limitations, the choice of an appropriate data source should be guided by a specific research objective. Selecting the most suitable RWD source according to the research question is essential for appropriately evaluating adverse drug reactions. This approach enables the assessment of diverse clinically relevant safety issues in cancer-related settings and supports the generation of evidence that reflects routine clinical practice.