Dosimetric Evaluation Of EBRT Combined With Intracavitary Brachytherapy For Cervical Carcinoma

Radiation therapy of Cervical Carcinoma is treated with a combinationmode of external irradiation and intracavitary brachytherapy at present. Thelocal control rate of radiotherapy and complications have a significantrelationship with the radiation dose and the irradiation volume. Only todetermine the radiation dose of the tumor target volume and organs at risk in theinternal and external radiotherapy accurately, can we improve the local tumorcontrol rate and reduce the surrounding normal tissue dose. In this paper, we usethe image-guided and image fusion techniques in order to track the movement ofthe target and the organs at risk. As the patients with cervical cancer who weretreated with a combination mode of intracavitary brachytherapy and IMRTtechnology external irradiation therapy, we want to implement the dynamicsuperposition about the dose of the internal and external radiotherapy and assessthe total radiation dose of the target and the organs at risk.The external irradiation scheme assessment shows there are no obviousdifferences of the IMRT and Rapidarc plan on dosimetry, but both of them arebetter than3D-CRT plans.For D2cc、D1cc and D0.1cc of bladder and rectum,3D plan is superior to2D plan for intracavitary brachytherapy of cervical carcinoma.And3D-RT ismore dominance than2D-RT in the ratio of gain for brachytherapyAll kinds of indices of IMRT group are suprior to those of3D-CRT groupthrough the dose calculation of extern-beam irradiation (IMRT and3D-CRTplans) and brachytherapy with3D-CRT technique after imging fusion.