Secondary cancer risks after breast radiotherapy: A dose-response-based comparative review across modern techniques
DOI:
https://doi.org/10.56294/saludcyt20251933Keywords:
Breast Neoplasms, Dose-response Relationship, Radiation, Neoplasms, Second primary Radiotherapy, Adjuvent, Radiotherpy, Intensity-ModulatedAbstract
Introduction:
Even with major progress in radiotherapy for breast cancer, secondary malignancy risks from unintentional radiation exposure to surrounding healthy organs remain a cause of worry, especially in long-term survivors. As survivorship improves, understanding and minimizing these risks is increasingly critical. Evaluating how different techniques impact secondary malignancies can guide safer treatment planning.
Objective:
The review aimed to identify the optimal radiotherapy techniques and organ-specific dose thresholds associated with secondary cancer risk after breast radiotherapy. The goal was to provide a full dose-risk overview to help in safer and more tailored treatment planning.
Methods:
The study comparatively evaluated organ-specific dose-response relationships and risk thresholds analyzing data from 24 studies published between 2019 and 2024 using PubMed and Google Scholar databases based on excess absolute risk, excess relative risk, and organ-equivalent dose models. Comparative outcome was performed across four radiotherapy techniques: three-dimensional conformal radiotherapy, intensity-modulated radiation therapy, volumetric-modulated arc therapy, and proton therapy including pencil beam scanning.
Results:
The analysis found that proton therapy and intensity-modulated radiotherapy with deep inspiration breath hold were linked with the lowest risks for organs at risk particularly the heart, lungs, esophagus, and contralateral breast. Younger patients have always higher risk, which emphasizes the need of customized radiotherapy planning.
Conclusions:
By synthesizing dose–response data and modeling results, it establishes organ-specific risk thresholds and generates technique-based risk profiles.The graphical and tabulated outputs offer practical guidance for treatment planning. Long-term outcome monitoring and patient-specific strategies should be given top priority in future studies.
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