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Purpose: To study the impact of MRI-guided treatment planning on dose/volume parameters in pulsed dose rate (PDR) brachytherapy (BT) for cervical cancer. Additionally, we investigated the potential benefit of an intracavitary/interstitial (IC/IS) modification of the classical tandem ovoid applicator.
Material And Methods: For 24 patients we compared Standard PDR BT plans, Scaled Standard plans and MRI-guided Optimised plans. The total EBRT/BT prescribed dose to Manchester point A or to 90% of the HR-CTV (D90 HR-CTV) expressed in EQD(2) was 80 Gy(alphabeta10) in 17 patients (Period I) and 84 Gy(alphabeta10) in 7 patients (Period II). The constraints to 2 cm(3) of the OAR were 90 Gy(alphabeta3) for bladder and 75 Gy(alphabeta3) for rectum, sigmoid and bowel. Most cases were treated with a traditional intracavitary tandem ovoid applicator. In 6 patients we used a newly designed combined IC/IS modification for the second PDR fraction and investigated the benefit of the interstitial part.
Results: The average gain of MRI-guided optimisation expressed in D90 HR-CTV was 4+/-9 Gy(alphabeta10) (p<0.001) and 10+/-7 Gy(alphabeta10) (p=0.003) in the two periods. The dose to 2 cm(3) of the OAR met the constraints. In the group that was treated with the combined IC/IS approach, we could increase the D90 HR-CTV for the second PDR fraction with 5.4+/-4.2 Gy(alphabeta10) (p=0.005) and the D100 with 4.8+/-3.1 Gy(alphabeta10) (p=0.07).
Conclusions: Three-dimensional MRI-guided treatment planning and optimisation improves the DVH parameters compared to conventional planning strategies. Additional improvement can be achieved by using a combined IC/IS approach.
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http://dx.doi.org/10.1016/j.radonc.2009.08.014 | DOI Listing |
Brachytherapy
August 2025
Department of Radiation Oncology, Osaka International Cancer Institute, Chuo-ku, Osaka, Japan.
Purpose: This study aimed to evaluate the inter-applicator differences in source positions of the Geneva and Venezia applicators by using X-ray fluoroscopy to perform direct measurements of iridium-192 (Ir) source positions.
Materials And Methods: Offset measurements of two to six sets of Geneva tandem and ovoid applicators and Venezia tandem applicators were performed. Each applicator was irradiated with Ir at the most distal position and X-ray fluoroscopy images were acquired.
Brachytherapy
August 2025
Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada; Department of Radiation Oncology, University of Toronto, Toronto, Ontario, Canada. Electronic address:
Purpose: Magnetic resonance image-guided brachytherapy (MRgBT) is the gold-standard treatment for cervical cancer. This study examined workflow times in an integrated MRgBT suite and conventional operating room (OR), and factors contributing to intraoperative efficiency.
Methods And Materials: Consecutive patients with FIGO stage IB-IVA cervical cancer who underwent MRgBT procedures between 2019-2022 were retrospectively reviewed.
J Contemp Brachytherapy
June 2025
Division of Radiation Oncology, Department of Radiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
Purpose: This study aimed to evaluate applicator displacement due to patient transfer using traditional fixation (TRD) with and without patient transfer system (TS), and to assess its dosimetric impact on organs at risk (OARs).
Material And Methods: Computed tomography (CT) images, including high-risk clinical target volume (HR-CTV) and OARs structures, were analyzed from 46 treatment plans involving 32 patients undergoing intracavitary brachytherapy with tandem-ovoid applicator, using either traditional fixation (TRD) alone or in combination with patient transfer system (TRD + TS). Applicator displacement was assessed by measuring the distance between applicator base in two sets of CT images: one acquired during treatment planning (pre-plan), and second at dose delivery (pre-load).
J Appl Clin Med Phys
July 2025
Department of Radiation Oncology, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Tokyo, Japan.
Purpose: This study aimed to investigate the effect of inverse planning parameters on dose-volume indices in brachytherapy for uterine cervical cancer.
Methods: Fourteen consecutive patients with cervical cancer who received intracavitary and interstitial brachytherapy (IC/ISBT) were selected. Tandem, ovoid, and interstitial needles were used in all cases.
J Cancer Res Ther
April 2025
Department of Physics, University College of Science, Osmania University, Hyderabad, Telangana, India.
Purpose: To compare the dosimetric parameters in hybrid brachytherapy with and without using the vaginal component for carcinoma cervix patients that do not have disease extending to the vagina.
Materials And Methods: Patients without vaginal involvement who received chemoradiation and hybrid brachytherapy were prospectively included for analysis. Two plans were created for each patient.