Application of three different kinds of local boost techniques in radiotherapy for locally advanced cervical cancer / 中华放射医学与防护杂志

ABSTRACT

Objective:To investigate the dosimetry differences in the treatment of locally advanced cervical cancer with intracavitary/interstitial brachytherapy (IC/IS BT), intracavity brachytherapy combined with intensity modulated radiotherapy (ICBT+ IMRT) and simple IMRT.Methods:Totally 16 patients with local advanced cervical cancer were retrospectively selected, which were treated by three-dimensional brachytherapy. On the basis of the original three-dimensional intracavitary/interstitial brachytherapy plan, ICBT+ IMRT and IMRT plans were designed respectively to study the dosimetry differences of target and different organs at risk for the three kinds of plans.Results:A total of 75 brachytherapy treatment plans were designed, including 25 IC/IS BT, 25 ICBT+ IMRT and 25 IMRT. There was not statistically significant difference of target dose parameters between ICBT+ IMRT and IC/IS BT plan ( P>0.05). ICBT+ IMRT plans had better OAR sparing than IC/IS BT. The doses of OARs in the IMRT plans were relatively large and the volume irradiated to more than 60 Gy ( V60) was significantly higher( t=6.77, 10.37, 4.61, 2.83, P<0.05). Conclusions:The ICBT+ IMRT technique not only provides better target coverage, but also maintains low doses to the OARS, which can be used as an alternative treatment to IC/IS BT. Although the target coverage of IMRT is better, the protection of OARs is not satisfied, so it is not suitable for local boost therapy of advanced cervical cancer.