The Medanta AOLO template for locally advanced cancer cervix brachytherapy: design and clinical implementation

Purpose
In advanced cervical cancers, improved techniques using both intracavitary and interstitial brachytherapy (IC + IS) should be used to adequately cover the residual tumor volume, resulting in better clinical results. Confronted with some limitation in implementing available applicators, we devised our own indigenous template that would also serve as an applicator.

Material and methods
First, a graphical design was drawn, keeping in mind the extent of volumes that need to be targeted in various brachytherapy scenarios. It was validated in a computer system and a physical template was manufactured. The template underwent modified versions through iterative dosimetric and planning exercises. The final model was successfully implemented in a clinical scenario.

Results
Cylindrical templates of diameter 3, 4, and 5 cm were produced with central aperture for central tandem, combining surrounding holes spaced at pre-planned points. The instrument can be used for IC + IS brachytherapy in cervical cancers. This easy to use applicator/template can direct needles to treat a distance of 4.5 cm laterally at the level of point A. In two initial applications 55 and 54 cc of high-risk clinical target volumes (HRCTV) were treated, and 90% of the HRCTV was covered by 96% and 97% of prescribed doses, respectively. Additionally, the needles guided by the template helped in sculpting the dose from bladder and rectum.

Conclusions
We have developed an easy to use IC + IS type of template/applicator, which was successfully implemented in our clinical practice.