PURPOSE: To ascertain the potential for dose reduction to bladder and rectal points by using intravaginal Foley balloon catheters as a mechanism for structural displacement during tandem and ovoid high-dose-rate intracavitary brachytherapy of the uterine cervix. METHODS AND MATERIALS: In 22 patients, two Foley balloons were placed intravaginally, with one balloon placed anterior to the tandem and one posterior, as close to the flange as patient geometry allowed. A series of 57 consecutive digitized treatment plans was assessed with and without liquid contrast inflation of Foley catheter balloons. Planning X-rays were acquired and digitized. Software calculated dose was then defined for two bladder and two rectal points, both with and without Foley balloon inflation. Results were then assessed using parametric statistical analysis. RESULTS: Collectively and between equivalent points, a statistically significant (p < or = 0.01) diminution in calculated dose was observed with inflation of intracavitary balloon catheters, with a mean reduction in calculated dose of 16% and 17.6% for bladder and rectal points, respectively. CONCLUSION: The potential advantages available from dose reduction using intracavitary balloon catheters include decreased high-dose-rate-induced organ toxicity, case-by-case customizability, and low cost of implementation. As such, further exploration of this technique is warranted.
PURPOSE: To ascertain the potential for dose reduction to bladder and rectal points by using intravaginal Foley balloon catheters as a mechanism for structural displacement during tandem and ovoid high-dose-rate intracavitary brachytherapy of the uterine cervix. METHODS AND MATERIALS: In 22 patients, two Foley balloons were placed intravaginally, with one balloon placed anterior to the tandem and one posterior, as close to the flange as patient geometry allowed. A series of 57 consecutive digitized treatment plans was assessed with and without liquid contrast inflation of Foley catheter balloons. Planning X-rays were acquired and digitized. Software calculated dose was then defined for two bladder and two rectal points, both with and without Foley balloon inflation. Results were then assessed using parametric statistical analysis. RESULTS: Collectively and between equivalent points, a statistically significant (p < or = 0.01) diminution in calculated dose was observed with inflation of intracavitary balloon catheters, with a mean reduction in calculated dose of 16% and 17.6% for bladder and rectal points, respectively. CONCLUSION: The potential advantages available from dose reduction using intracavitary balloon catheters include decreased high-dose-rate-induced organ toxicity, case-by-case customizability, and low cost of implementation. As such, further exploration of this technique is warranted.
Authors: Qiyong Fan; Anamaria R Yeung; Robert Amdur; Richard Helmig; Justin Park; Jonathan Li; Darren Kahler; Chihray Liu; Bo Lu Journal: Technol Cancer Res Treat Date: 2016-02-10