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Updated: Dec 21, 2025
08:34
Proton Therapy Delivery and Its Clinical Application in Select Solid Tumor Malignancies
Published on: February 6, 2019
20.9K
Radiobiological effectiveness difference of proton arc beams versus conventional proton and photon beams
Alejandro Carabe1,2, Ilias V Karagounis1, Kiet Huynh1
1Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, PA, United States of America.
Physics in Medicine and Biology
|May 16, 2020
Summary
Proton monoenergetic arc therapy (PMAT) shows up to 43% greater biological effectiveness than intensity modulated proton therapy (IMPT), inducing more complex DNA damage. This suggests PMAT could enhance tumor control probability.
Area of Science:
- Radiation Oncology
- Medical Physics
- Cell Biology
Background:
- Proton therapy offers advantages over photon therapy due to its physical properties.
- Comparing different proton therapy techniques is crucial for optimizing treatment efficacy.
- Understanding the biological effectiveness and DNA damage response is key to advancing cancer treatment.
Purpose of the Study:
- To compare the biological effectiveness of proton monoenergetic arc therapy (PMAT) against intensity modulated proton therapy (IMPT) and 6 MV photon therapy.
- To quantify differences in cell survival and DNA damage induction across these modalities.
- To evaluate the DNA repair kinetics following exposure to PMAT, IMPT, and photons.
Main Methods:
- Cell cultures (V79, H1299, H460) were irradiated with PMAT, IMPT, and 6 MV photon beams.
- Clonogenic assays were used to measure cell survival and relative biological effectiveness (RBE).
- Gamma-H2AX assays assessed DNA damage quantity, quality, and repair rates over time.
Main Results:
- PMAT demonstrated a significant increase in biological effectiveness, up to 43% higher than IMPT.
- PMAT induced more complex and persistent DNA damage, evidenced by slower repair kinetics compared to IMPT.
- Cell survival levels were similar for IMPT and 6 MV photon therapy at equivalent doses.
Conclusions:
- Proton monoenergetic arc therapy (PMAT) exhibits superior biological effectiveness compared to intensity modulated proton therapy (IMPT).
- PMAT induces more severe and complex DNA damage, potentially leading to enhanced tumor control.
- Further in vivo studies are warranted to validate these findings for clinical application.
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