Impact of time-related factors on biologically accurate radiotherapy treatment planning.
Radiat Oncol
; 13(1): 30, 2018 Feb 23.
Article
in En
| MEDLINE
| ID: mdl-29471859
ABSTRACT
BACKGROUND:
The incomplete repair (IR) model expresses the cell repair effect from radiation-induced damage over time, which is given little consideration in actual treatment planning. By incorporating the IR model into the normal tissue complication probability (NTCP), the accuracy and safety of treatment plan evaluations concerning the effect of repair can be improved. This study aims to evaluate the impact of incorporating the IR model into the NTCP by varying time-related factors such as the repair half-time (T1/2) and the junction-shift sc3hedule in craniospinal irradiation (CSI).METHODS:
CSI was planned retrospectively, and the NTCP of the spinal cord was calculated with the IR model for values of T1/2 from 1 to 10 h. The NTCP in the case of changing the junction-shift schedule was also examined in the same manner.RESULTS:
The NTCP with the IR model increased with increasing T1/2, which is prominent for the larger T1/2. By changing the junction-shift schedule, the NTCP with the IR model decreased when adjacent fields overlapped.CONCLUSIONS:
The IR model is a valuable addition to treatment planning because it enables the NTCP to be evaluated including the effect of repair and differences in scheduling to be reflected in the NTCP. However, these are largely dependent on the value of the T1/2.
Full text:
1
Database:
MEDLINE
Main subject:
Radiation Injuries
/
Spinal Cord Neoplasms
/
Algorithms
/
Radiotherapy Planning, Computer-Assisted
/
Brain Neoplasms
Type of study:
Observational_studies
/
Prognostic_studies
Limits:
Humans
Language:
En
Year:
2018
Type:
Article