Published online Apr 28, 2017. doi: 10.4329/wjr.v9.i4.148
Peer-review started: September 2, 2016
First decision: September 26, 2016
Revised: December 15, 2016
Accepted: January 16, 2017
Article in press: January 18, 2017
Published online: April 28, 2017
Processing time: 241 Days and 15.1 Hours
Traditional brachytherapy refers to the placement of radioactive sources on or inside the cancer tissues. Based on the type of sources, brachytherapy can be classified as radionuclide and electronic brachytherapy. Electronic brachytherapy uses miniaturized X-ray sources instead of radionuclides to deliver high doses of radiation. The advantages of electronic brachytherapy include low dose to organs at risk, reduced dose to treating staff, no leakage radiation in off state, less shielding, and no radioactive waste. Most of these systems operate between 50 and 100 kVp and are widely used in the treatment of skin cancer. Intrabeam, Xoft and Papillon systems are also used in the treatment of intra-operative radiotherapy to breast in addition to other treatment sites. The rapid fall-off in the dose due to its low energy is a highly desirable property in brachytherapy and results in a reduced dose to the surrounding normal tissues compared to the Ir-192 source. The Xoft Axxent brachytherapy system uses a 2.25 mm miniaturized X-ray tube and the source almost mimics the high dose rate Ir-192 source in terms of dose rate and it is the only electronic brachytherapy system specifically used in the treatment of cervical cancers. One of the limiting factors that impede the use of electronic brachytherapy for interstitial application is the source dimension. However, it is highly anticipated that the design of miniaturized X-ray tube closer to the dimension of an Ir-192 wire is not too far away, and the new era of electronic brachytherapy has just begun.
Core tip: Electronic brachytherapy is a new form of radiotherapy that delivers a very high dose of radiation inside or very close to the cancer tissues. These devices utilize a miniaturized X-ray source to deliver radiation at relatively high dose rates to the target volume. Electronic brachytherapy eliminates some of the accidents related to radionuclide brachytherapy such as loss of sources, radiation leakage in off state, transportation accidents and radioactive waste. It finds wide applications in the treatment of cancers including skin, breast, endometrium, cervix and spinal metastasis. Electronic brachytherapy is a promising technology of the future and could potentially replace radionuclide brachytherapy.