Research of Biological Dose Conversion Platform Based on a Modified Linear Quadratic Model

Area of Science:

• Radiation oncology
• Medical physics
• Mathematical modeling

Background:

• The linear-quadratic (LQ) model is standard for radiobiology but has limitations with high doses per fraction.
• Accurate dose conversion is crucial for optimizing radiotherapy, particularly with hypofractionation.

Purpose of the Study:

• To develop a novel dose conversion platform by improving the LQ model for high fraction/acute doses.
• To enhance the accuracy of radiation response description and dose calculation.

Main Methods:

• Modified the LQ model using piecewise fitting of biological dose curves.
• Optimized the mathematical model for consistency with experimental data.
• Applied the modified model to compare hypofractionated and conventional fractionated doses.

Main Results:

• The improved LQ model accurately describes radiation response across a range of doses, including high doses.
• Calculated equivalent doses for treatments with the same efficacy showed consistency regardless of the alpha/beta ratio.
• The model provides a more rational explanation for differences observed in various hypofractionation schemes.

Conclusions:

• The modified biologically effective dose model overcomes LQ model inaccuracies at high doses.
• The platform enables a more rational evaluation of dose effects for different cell types and fractionation schedules.
• The equivalent uniform dose calculation method supports detailed evaluation of dose effects in complex distributions.