当前位置： SCI文献检索 > INTERNATIONAL JOURNAL OF RADIATION BIOLOGY期刊下所有文献 > The application of the linear quadratic model to compensate the effects of prolonged fraction delivery time on a Balb/C breast adenocarcinoma tumor: An in vivo study.

The application of the linear quadratic model to compensate the effects of prolonged fraction delivery time on a Balb/C breast adenocarcinoma tumor: An in vivo study.

Abstract：

:Purpose To investigate the effect of increasing the overall treatment time as well as delivering the compensating doses on the Balb/c breast adenocarcinoma (4T1) tumor. Materials and methods A total of 72 mice were divided into two aliquots (classes A and B) based on the initial size of their induced tumor. Each class was divided into a control and several treatment groups. Among the treatment groups, group 1 was continuously exposed to 2 Gy irradiation, and groups 2 and 3 received two subfractions of 1 Gy over the total treatment times of 30 and 60 min, respectively. To investigate the effect of compensating doses, calculated based on the developed linear quadratic model (LQ) model, the remaining two groups (groups 4 and 5) received two subfractions of 1.16 and 1.24 Gy over the total treatment times of 30 and 60 min, respectively. The growing curves, Tumor Growth Time (TGT), Tumor Growth Delay Time (TGDT) and the survival of the animals were studied. Results For class A (tumor size ≤ 30 mm(3)), the average tumor size in the irradiated groups 1-5 was considerably different compared to the control group as one unit (day) change in time, by amount of -160.8, -158.9, +39.4 and +44.0, respectively. While these amounts were +22.0, +17.9, -21.7 and -0.1 for class B (tumor size ≥ 400 mm(3)). For the class A of animals, the TGT and TGDT parameters were significantly lower (0 ≤ 0.05) for the groups 2 and 3, compared to group 1. There was no significant difference (p > 0.05) between groups 1, 4 and 5 in this class. There was no significant difference (p > 0.05) between all the treated groups in class B. Conclusions Increasing total treatment time affects the radiobiological efficiency of treatment especially in small-sized tumor. The compensating doses derived from the LQ model can be used to compensate the effects of prolonged treatment times at in vivo condition.

journal_name

Int J Radiat Biol

journal_title

International journal of radiation biology

authors

Nikzad S,Hashemi B,Hasan ZS,Mozdarani H,Baradaran-Ghahfarokhi M,Amini P

doi

10.3109/09553002.2016.1117677

subject

Has Abstract

pub_date

2016-01-01 00:00:00

pages

80-6

issue

eissn

0955-3002

issn

1362-3095

journal_volume

pub_type

杂志文章

在线工具

The application of the linear quadratic model to compensate the effects of prolonged fraction delivery time on a Balb/C breast adenocarcinoma tumor: An in vivo study.