Abstract PS5-10-01: Misinformation about breast cancer treatment on social media: Implications for engagement with patients and social media

Abstract Background: Despite lack of clinical trial data supporting drug efficacy or safety, many patients request alternative treatments, such as ivermectin, fenbendazole, mebendazole, and methylene blue, over standard treatments. Social media (SM) is widely available, highly utilized and a likely source of information about alternative treatments. However, SM content on alternative therapies has not been analyzed to inform engagement by oncology providers with the lay public. Methods: We used Infegy, a SM listening platform, to search for content about alternative treatments for breast cancer across SM platforms (Twitter/X, Reddit, Meta platforms) from June 2021 to June 2025. We conducted an initial search for all content about “breast cancer” to establish the denominator of content and provide a comparison. We then conducted a focused search using Boolean logic combining “breast cancer” with “ivermectin,” “methylene blue,” “fenbendazole,” “mebendazole,” and alternative names for each. Infegy provides descriptive information about content captured (e.g., # of posts, people reached, unique impressions), prominent topics, and prominent sources of posts (i.e., account handles). We manually analyzed the content of a subset of posts from the focused search to determine if they were endorsing alternative treatments, asking questions about them, or opposing them. Results: In the initial search for “breast cancer”, there were >3.1 million (M) posts with a potential reach of >33.2 billion people and generated >421M unique impressions. Prominent breast cancer themes included awareness, support, treatment, and survivorship. Prominent sources of content included cancer research and advocacy organizations (e.g., American Cancer Society, Susan G. Komen Foundation, Breast Cancer Research Foundation). In the focused search for alternative therapies, there were >370,000 posts (12% of all breast cancer posts), potentially reaching >55M people and generating >418,000 unique impressions. Prominent sources of content included health professionals affiliated with companies that promote alternative treatments, websites that sell alternative treatments, and suspected “bot” accounts. Common topics included personal testimonials and discussions about treatments, chemotherapy, and described “cures.” Most posts mentioned (not mutually exclusive) ivermectin (344/410, 84%), methylene blue (56/410, 14%), mebendazole (27/410, 7%), and fenbendazole (11/410, 3%). Overall, 73% of posts analyzed (299/410) endorsed these alternative treatments, whereas only a minority asked questions (30/410, 7%) or opposed them (20/410, 5%), and 30 posts (7%) could not be categorized. Examples of posts endorsing alternative treatments included personal testimonials and online retailers selling the treatments. Of the 410 posts from the focused search, 196 were unique content (48%) and manual review of example posts indicates much of the content may be generated by suspected “bots.” Conclusions: Although it represents a minority of SM content surrounding breast cancer, content promoting and endorsing alternative treatments for breast cancer reached an estimated >55M people. Most content promotes treatments that are (1) not guideline concordant and/or endorsed by oncology experts, and (2) have no supporting scientific evidence of safety or efficacy for breast cancer. Our data suggest the bulk of content promoting such treatments may be from automated accounts or “bots.” Given the wide-reaching impact of these SM posts, these findings highlight a need for information about evidence-based treatments in SM discussions, a need to equip breast cancer advocates and oncology providers to have such discussions with breast cancer patients, and a need for policies to prevent misinformation about breast cancer treatment on SM. Citation Format: M. Gatti-Mays, K. Koehler, A. VanLaven, L. Long, E. Alvardo, K. Noce, D. Stover, S. Collins, D. Mays. Misinformation about breast cancer treatment on social media: Implications for engagement with patients and social media [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS5-10-01.