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Published on: May 9, 2014
Normal tissue complication probabilities: variable dose per fraction
1Lawrence Berkeley Laboratory, University of California, Berkeley 94720.
International Journal of Radiation Oncology, Biology, Physics
|January 1, 1992
Summary
New tools optimize radiation therapy plans by estimating tumor control and normal tissue complication probability (NTCP). This study assesses how varying daily radiation doses impact NTCP calculations for improved treatment accuracy.
Area of Science:
- Radiation oncology
- Medical physics
- Radiotherapy planning
Background:
- 3D treatment planning generates vast data, necessitating advanced tools for plan evaluation and optimization.
- Estimating local tumor control and normal tissue complication probability (NTCP) are key advancements.
- Current NTCP models rely on clinical tolerance doses, typically for 2 Gy/fraction, 5 fractions/week schedules.
Purpose of the Study:
- To evaluate the maximum expected change in Normal Tissue Complication Probability (NTCP).
- To assess NTCP variations when normal tissues receive doses at different dose-per-fraction rates compared to the target volume.
- To understand the impact of varied daily fraction delivery on NTCP predictions.
Main Methods:
- Analysis of Normal Tissue Complication Probability (NTCP) models.
- Comparison of NTCP calculations under standard versus altered dose-per-fraction scenarios.
- Evaluation of dose delivery variations between target volumes and surrounding normal structures.
Main Results:
- Identified potential discrepancies in NTCP predictions when dose per fraction differs between target and normal tissues.
- Quantified the maximum expected change in NTCP under non-standard fractionation schedules.
- Highlighted the sensitivity of NTCP calculations to variations in daily radiation dose delivery.
Conclusions:
- Standard NTCP models may require adjustments when non-uniform fractionation is employed.
- The study underscores the importance of considering dose per fraction variations for accurate NTCP assessment.
- Findings support the development of more robust tools for optimizing radiotherapy plans considering complex fractionation schemes.
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