Background/Objectives: Cancer therapy-induced alopecia (CTIA) profoundly affects patients’ quality of life. This study conducted a disproportionality analysis of CTIA using the FDA Adverse Event Reporting System (FAERS) database to provide an overview of drug-specific signal distributions by systematically evaluating the impact of reporter type on CTIA signal detection. Methods: FAERS data from January 2004 to September 2024 were analyzed to extract alopecia-related Preferred Terms included under the Medical Dictionary for Regulatory Activities High Level Term “Alopecias.” Reporting odds ratios (RORs) were calculated to assess disproportionality. A primary analysis including all reports and a stratified analysis restricted to reports submitted by healthcare professionals (HCPs) were performed. No individual case-level clinical review was conducted. Results: Approximately 90% of alopecia reports were associated with female patients, and approximately 40% of these reports were linked to breast cancer. In the disproportionality analysis including all reporters, the highest ROR 95% confidence interval (CI) was observed for docetaxel 58.31 (57.46–59.17). In the analysis restricted to HCP reports, the highest ROR was observed for vismodegib 23.92 (21.86–26.17), whereas that for docetaxel markedly decreased to 3.68 (3.48–3.89). For molecular targeted agents, statistically significant signals were maintained even in the HCP-restricted analysis. Conclusions: Reporter characteristics substantially influence the detection of alopecia signals, with patients amplifying signals reflecting psychological harm and HCPs amplifying signals reflecting pharmacological plausibility. These findings should be interpreted as hypothesis-generating and warrant further validation using prospective or clinical datasets.
Yajima et al. (Tue,) studied this question.