Rethinking Breast Cancer Screening: New Insights on Overdiagnosis

BUFFALO, NY – March 12, 2025 – A new #editorial was #published in Oncotarget, Volume 16, on March 10, 2025, titled “COMETgazing – interesting insights, lessons for clinical practice and a call for more precision using the biomarkerSCOPE.” Dr. Mangesh A. Thorat, affiliated with Queen Mary University of London, Homerton University Hospital, and King’s College London, discusses new findings suggesting that some women diagnosed with early-stage breast cancer may not need immediate surgery. The editorial is based on results from the COMET trial, which studied women with low- to intermediate-grade ductal carcinoma in situ (DCIS). The findings raise questions about the necessity of surgery and highlight the importance of more precise screening methods for DCIS, ensuring that only those who truly need treatment receive it. Breast cancer screening programs are designed to detect cancer early, but this editorial reinforces the concern that some detected cancers may never become a real threat. The COMET trial compared two strategies for treating breast cancer: standard treatment, which includes surgery and possible additional therapy, versus active monitoring, where patients are closely observed without immediate intervention. The results indicate that many of the invasive cancers diagnosed in the monitoring group were likely present from the start rather than developing from DCIS over time. Dr. Thorat points out that these invasive cancers were often slightly larger, but they did not appear to be aggressive. These findings challenge the assumption that immediate treatment is necessary for all cases of DCIS. Researchers estimate that at least half of the invasive breast cancers in this study either take years to progress or may never progress at all. “The planned long-term follow-up of the trial may shed more light on the median length of lead-time and the proportion of IBCs regressing as well as DCIS progression under different lead-time assumptions.” Current methods for evaluating DCIS rely heavily on histological grading, which has limitations. Dr. Thorat emphasizes the need for more precise tools to determine which DCIS cases require treatment. His previous research suggests that biomarkers, such as multi-clonal estrogen receptor (ER) expression and tumor-infiltrating lymphocytes (TILs), may help predict which DCIS cases are truly at risk of becoming invasive. The editorial also highlights that many women prefer to avoid surgery when possible. In a related study, only 52% of patients in the standard care group followed through with it, indicating that more individuals are willing to consider alternatives to surgery. This fact underscores the importance of developing accurate biomarkers to guide treatment decisions and ensure that patients receive appropriate care without unnecessary interventions. As researchers continue to follow patients from the COMET trial, they hope to learn more about how invasive breast cancers behave over time. Finally, Dr. Thorat encourages clinicians and scientists to rethink breast cancer treatment and develop better ways to identify which patients truly need surgery—and which do not. DOI - https://doi.org/10.18632/oncotarget.28698 Correspondence to - Mangesh A. Thorat - m.thorat@qmul.ac.uk To learn more about Oncotarget, please visit https://www.oncotarget.com and connect with us: Facebook - https://www.facebook.com/Oncotarget/ X - https://twitter.com/oncotarget Instagram - https://www.instagram.com/oncotargetjrnl/ YouTube - https://www.youtube.com/@OncotargetJournal LinkedIn - https://www.linkedin.com/company/oncotarget Pinterest - https://www.pinterest.com/oncotarget/ Reddit - https://www.reddit.com/user/Oncotarget/ Spotify - https://open.spotify.com/show/0gRwT6BqYWJzxzmjPJwtVh MEDIA@IMPACTJOURNALS.COM