Abstract
Examining the applicability of the linear-quadratic (LQ) concept for prediction of late rectum and rectosigmoid complications due to combined irradiation of the uterine cervix, it appears that an agreement between clinical experiences and the LQ-based tolerance model can be achieved when relative high tolerance dose values for the separate irradiation techniques are assumed: 70 Gy in 28 fractions for the fractionated irradiation, 70 Gy in 6 days for the continuous irradiation. These tolerance values are derived by assuming a value of 2.5 for the biological parameter a1/a2 (or alpha/beta) as suggested by the LQ-model to be a good approximation for studies of late effects. This investigation shows how fractional tolerance values can be derived for the continuous and fractionated irradiation components. From a simple addition of these values, the total biological effectiveness of a combined irradiation treatment can be determined. This provides a model based on radiobiological parameters for comparison of different treatment schedules, and for dose-adjustments to be made in individual treatments. Especially in cases where the introduction of new afterloading techniques is accompanied by changes in dose rate of the intracavitary irradiation, the LQ-model offers a possibility to prevent mistakes in dosage of critical organs.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
