Clinical Investigation: Gynecologic Cancer BladdereRectum Spacer Balloon in High-Dose-Rate Brachytherapy in Cervix Carcinoma Bhavana Rai, MD,* Firuza D. Patel, MD,* Santam Chakraborty, MD,* Suresh C. Sharma, MD,* Rakesh Kapoor, MD,* and Abi Santhosh Aprem, PhD y *Department of Radiotherapy and Oncology, Regional Cancer Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India; and y Corporate R&D Division, HLL Lifecare Limited, Karamana, Trivandrum, India Received Aug 6, 2012, and in revised form Sep 26, 2012. Accepted for publication Sep 28, 2012 Summary This was a randomized study to evaluate bladder and rectum doses using a bladder erectum spacer balloon (BRSB) and standard gauze packing in the same patient receiving 2 HDR brachy- therapy fractions. Significant dose reduction to the small high-dose volumes of rectum was observed with BRSB. The doses to bladder were comparable. In addition to improved dosimetry, the BRSB may offer greater reproducibility and stan- dardized displacement of the bladder and rectum in multiple HDR brachytherapy applications. Purpose: To compare bladder and rectum doses with the use of a bladdererectum spacer balloon (BRSB) versus standard gauze packing in the same patient receiving 2 high-dose-rate intracavitary brachytherapy fractions. Methods and Materials: This was a randomized study to compare the reduction in bladder and rectum doses with the use of a BRSB compared with standard gauze packing in patients with carcinoma of the cervix being treated with high-dose-rate intracavitary brachytherapy. The patients were randomized between 2 arms. In arm A, vaginal packing was done with standard gauze packing in the first application, and BRSB was used in the second application. Arm B was the reverse of arm A. The International Commission for Radiation Units and Measurement (ICRU) point doses and doses to 0.1-cm 3 , 1-cm 3 , 2-cm 3 , 5-cm 3 , and 10-cm 3 volumes of bladder and rectum were compared. The patients were also subjectively assessed for the ease of application and the time taken for application. Statistical analysis was done using the paired t test. Results: A total of 43 patients were enrolled; however, 3 patients had to be excluded because the BRSB could not be inserted owing to unfavorable local anatomy. Thus 40 patients (80 plans) were evaluated. The application was difficult in 3 patients with BRSB, and in 2 patients with BRSB the application time was prolonged. There was no significant difference in bladder doses to 0.1 cm 3 , 1 cm 3 , 2 cm 3 , 5 cm 3 , and 10 cm 3 and ICRU bladder point. Statistically significant dose reductions to 0.1-cm 3 , 1-cm 3 , and 2-cm 3 volumes for rectum were observed with the BRSB. No significant differences in 5-cm 3 and 10-cm 3 volumes and ICRU rectum point were observed. Conclusion: A statistically significant dose reduction was observed for small high-dose volumes in rectum with the BRSB. The doses to bladder were comparable for BRSB and gauze packing. Transparent balloons of variable sizes are recommended for patients with a less spacious vaginal cavity. Ó 2013 Elsevier Inc. Reprint requests to: Firuza D. Patel, MD, Department of Radiotherapy and Oncology, Regional Cancer Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, UT 160012, India. Tel: (91) 977- 9124440; E-mail: firuzapatel@gmail.com The bladdererectum spacer balloon was provided by HLL Lifecare Limited. Conflict of interest: none. Int J Radiation Oncol Biol Phys, Vol. 85, No. 5, pp. e217ee222, 2013 0360-3016/$ - see front matter Ó 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ijrobp.2012.09.037 Radiation Oncology International Journal of biology physics www.redjournal.org