open access

Vol 23, No 1 (2018)
Original research articles
Published online: 2018-01-01
Submitted: 2017-03-14
Get Citation

Dosimetric evaluation of image based brachytherapy using tandem ovoid and tandem ring applicators

Ramya Rangarajan
DOI: 10.1016/j.rpor.2017.12.006
·
Rep Pract Oncol Radiother 2018;23(1):57-60.

open access

Vol 23, No 1 (2018)
Original research articles
Published online: 2018-01-01
Submitted: 2017-03-14

Abstract

Aim

The aim of the study is to evaluate the differences in dosimetry between tandem-ovoid and tandem-ring gynaecologic brachytherapy applicators in image based brachytherapy.

Background

Traditionally, tandem ovoid applicators were used to deliver dose to tumor in intracavitary brachytherapy. Tandem-ring, tandem-cylinder and hybrid intracavitary, interstitial applicators are also used nowadays in cervical cancer brachytherapy.

Methods and materials

100 CT datasets of cervical cancer patients (stage IB2 – IIIB) receiving HDR application (50 tandem-ovoid and 50 tandem-ring) were studied. Brachytherapy was delivered using a CT-MRI compatible tandem-ovoid (50 patients) and a tandem-ring applicator (50 patients). DVHs were calculated and D2cc was recorded for the bladder and rectum and compared with the corresponding ICRU point doses. The point B dose, the treated volume, high dose volume and the treatment time were recorded and compared for the two applicators.

Results

The mean D2cc of the bladder with TR applicator was 6.746[[ce:hsp sp="0.25"/]]Gy. TO applicator delivered a mean D2cc of 7.160[[ce:hsp sp="0.25"/]]Gy to the bladder. The mean ICRU bladder points were 5.60 and 5.63[[ce:hsp sp="0.25"/]]Gy for TR and TO applicator, respectively. The mean D2cc of the rectum was 4.04[[ce:hsp sp="0.25"/]]Gy and 4.79[[ce:hsp sp="0.25"/]]Gy for TR and TO applicators, respectively. The corresponding ICRU point doses were 5.10[[ce:hsp sp="0.25"/]]Gy and 5.66[[ce:hsp sp="0.25"/]]Gy, respectively.

Conclusions

The results indicate that the OAR doses assessed by DVH criteria were higher than ICRU point doses for the bladder with both tandem-ovoid and tandem-ring applicators whereas DVH based dose was lower than ICRU dose for the rectum. The point B dose, the treated volume and high dose volume was found to be slightly higher with the tandem-ovoid applicator. The mean D2cc dose for the bladder and rectum was lower with tandem-ring applicators. The clinical implication of the above dosimetric differences needs to be evaluated further.

Abstract

Aim

The aim of the study is to evaluate the differences in dosimetry between tandem-ovoid and tandem-ring gynaecologic brachytherapy applicators in image based brachytherapy.

Background

Traditionally, tandem ovoid applicators were used to deliver dose to tumor in intracavitary brachytherapy. Tandem-ring, tandem-cylinder and hybrid intracavitary, interstitial applicators are also used nowadays in cervical cancer brachytherapy.

Methods and materials

100 CT datasets of cervical cancer patients (stage IB2 – IIIB) receiving HDR application (50 tandem-ovoid and 50 tandem-ring) were studied. Brachytherapy was delivered using a CT-MRI compatible tandem-ovoid (50 patients) and a tandem-ring applicator (50 patients). DVHs were calculated and D2cc was recorded for the bladder and rectum and compared with the corresponding ICRU point doses. The point B dose, the treated volume, high dose volume and the treatment time were recorded and compared for the two applicators.

Results

The mean D2cc of the bladder with TR applicator was 6.746[[ce:hsp sp="0.25"/]]Gy. TO applicator delivered a mean D2cc of 7.160[[ce:hsp sp="0.25"/]]Gy to the bladder. The mean ICRU bladder points were 5.60 and 5.63[[ce:hsp sp="0.25"/]]Gy for TR and TO applicator, respectively. The mean D2cc of the rectum was 4.04[[ce:hsp sp="0.25"/]]Gy and 4.79[[ce:hsp sp="0.25"/]]Gy for TR and TO applicators, respectively. The corresponding ICRU point doses were 5.10[[ce:hsp sp="0.25"/]]Gy and 5.66[[ce:hsp sp="0.25"/]]Gy, respectively.

Conclusions

The results indicate that the OAR doses assessed by DVH criteria were higher than ICRU point doses for the bladder with both tandem-ovoid and tandem-ring applicators whereas DVH based dose was lower than ICRU dose for the rectum. The point B dose, the treated volume and high dose volume was found to be slightly higher with the tandem-ovoid applicator. The mean D2cc dose for the bladder and rectum was lower with tandem-ring applicators. The clinical implication of the above dosimetric differences needs to be evaluated further.

Get Citation

Keywords

Intracavitary brachytherapy; Tandem-ovoid; Tandem-ring

About this article
Title

Dosimetric evaluation of image based brachytherapy using tandem ovoid and tandem ring applicators

Journal

Reports of Practical Oncology and Radiotherapy

Issue

Vol 23, No 1 (2018)

Pages

57-60

Published online

2018-01-01

DOI

10.1016/j.rpor.2017.12.006

Bibliographic record

Rep Pract Oncol Radiother 2018;23(1):57-60.

Keywords

Intracavitary brachytherapy
Tandem-ovoid
Tandem-ring

Authors

Ramya Rangarajan

Important: This website uses cookies. More >>

The cookies allow us to identify your computer and find out details about your last visit. They remembering whether you've visited the site before, so that you remain logged in - or to help us work out how many new website visitors we get each month. Most internet browsers accept cookies automatically, but you can change the settings of your browser to erase cookies or prevent automatic acceptance if you prefer.

By "Via Medica sp. z o.o." sp.k., ul. Świętokrzyska 73, 80–180 Gdańsk, Poland
tel.:+48 58 320 94 94, fax:+48 58 320 94 60, e-mail: journals@viamedica.pl