Use of subjective minimizing language in adverse event (AE) reporting in advanced cholangiocarcinoma (CCA) clinical trials.

390 Background: Despite advancements in diagnosis and treatment of CCA, outcomes remain suboptimal. Systemic therapies employed for palliative treatment of advanced CCA are associated with significant toxicities. Studies in other malignancies have noted the use of subjective minimizing language that significantly understates the severity of AEs on clinical trials. The euphemistic use of similar language may directly influence the use of these therapies in clinical practice. We sought to evaluate the use of subjective minimizing terms in AE reporting across CCA clinical trials. Methods: We searched PubMed/Medline to identify and include systemic therapy clinical trials including patients with unresectable or advanced CCA (2020-2025). We then evaluated their published manuscripts for usage of subjective terms to describe treatment-related AEs—including mild, reversible, manageable, acceptable, expected, tolerable, favorable, and safe. Univariate logistic regression analysis was performed using SPSS to evaluate the association between the frequency of grade 3/4 adverse events and the presence of minimizing terminology, using odds ratios with 95% confidence intervals. Results: Of 40 clinical trials, 37 (92.5%) utilized a minimizing term to describe AEs. Most frequently used were manageable (40%), tolerable (40%), and safe (32.5%). Other commonly used terms were well-tolerated (25%), favorable (20%), mild (15%), acceptable (12.5%), expected (7.5%), and reversible (2.5%). Of 37, 6 (16.2%) reported patient-reported outcomes (PROs). Grade 3 or 4 AE rates were reported with a median rate of 49% (IQR 30%, 69.6%) while Grade 5 AEs had an overall low incidence. Univariate logistic regression showed no association between the grade 3/4 AE rates (OR = 0.98 [95% CI .59-1.63] per 10% AE rate increase), and the use of minimizing terms. Conclusions: This study reveals the frequent use of minimizing terms for AE reporting in advanced CCA clinical trials. However, their usage was not associated with the actual incidence of grade 3/4 AEs. Additionally, most clinical trials did not report PROs. These findings highlight the need for more transparent and patient-centered AE reporting in future CCA clinical trials.