Comparison of different treatment planning optimization methods for vaginal HDR brachytherapy with multichannel applicators: A reduction of the high doses to the vaginal mucosa is possible

Carrara, M.; Cusumano, D.; Giandini, T.; Tenconi, C.; Mazzarella, E.; Grisotto, S.; Massari, E.; Mazzeo, Davide; Cerrotta, Annamaria; Pappalardi, Brigida; Fallai, C.; Pignoli, E.

doi:10.1016/j.ejmp.2017.11.007

Cited by 14 publications

(13 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As reported in Ref. [19] and [35], HIPO allows optimizing the intracavitary applicator and the interstitial needles separately to increase the proportion of dwell time of tandem in total time and reduce hot spots around needles. However, as the number of dwell positions for our cases was limited, the separate optimization with iterative approach had more limited degree of freedom for dwell time optimization.…”

Section: Discussionmentioning

confidence: 98%

Comparison of Two Inverse Planning Algorithms for Cervical Cancer Brachytherapy

Zuo

et al. 2020

Preprint

View full text Add to dashboard Cite

Purpose: To compare two methods, the hybrid inverse planning optimization (HIPO) algorithm and the inverse planning simulated annealing (IPSA) algorithm, for cervical cancer brachytherapy and provide suggestions for their usage.Material and methods: This study consisted of 24 cervical cancer patients treated with CT image-based high-dose-rate brachytherapy using various combinations of tandem/ovoid applicator and interstitial needles. For fixed catheter configurations, plans were retrospectively optimized with two methods: IPSA and HIPO. The dosimetric parameters with respect to target coverage, localization of high dose volume (LHDV), conformal index (COIN), and sparing of organs at risk (OARs) were evaluated. A plan assessment method which combines a graphical analysis and a scoring index was used to compare the quality of two plans for each case. The characteristics of dwell time distributions of the two plans were also analyzed.Results: Both IPSA and HIPO can produce clinically acceptable treatment plans. The rectum D2cc was slightly lower for HIPO as compared to IPSA (p=0.002). All other dosimetric parameters for targets and OARs were not significantly different between the two algorithms. The generated radar plots and scores intuitively presented the plan properties and enabled to reflect the clinical priorities for the treatment plans. Different characteristics were observed between the dwell time distributions generated by IPSA and HIPO. Conclusions: Despite significant difference in dwell time distributions, both the two algorithms could generate high-quality treatment plans. With the help of the plan assessment method, the clinical decision on the optimal plan can be made quickly and consistently for each patient.

show abstract

Section: Discussionmentioning

confidence: 98%

Comparison of Two Inverse Planning Algorithms for Cervical Cancer Brachytherapy

Zuo

et al. 2020

Preprint

View full text Add to dashboard Cite

show abstract

“…Kannan et al [10] found that IPSA significantly improved the target volume coverage compared with manual planning. Inverse planning in vaginal BT performed with multichannel applicator was also studied, and its dosimetric advantages were demonstrated using planning data in two studies with twelve patients in both investigations [14,15]. For other sites, information about inverse planning in BT is sparsely available.…”

Section: Discussionmentioning

confidence: 99%

“…In BT, apart from prostate cancer, the integration of inverse planning into clinical routine has not been accomplished so far. In the literature, there are reports on the use of inverse planning for cervix cancer [7,8,9,10,11,12,13], vaginal irradiation [14,15], and head and neck brachytherapy [16,17]. For breast cancer, the available information is scarce.…”

Section: Purposementioning

confidence: 99%

Does inverse planning improve plan quality in interstitial high-dose-rate breast brachytherapy?

Major¹,

Fröhlich²,

Mészáros³

et al. 2020

jcb

View full text Add to dashboard Cite

Purpose: To investigate the effect of input parameters for an inverse optimization algorithm, and dosimetrically evaluate and compare clinical treatment plans made by inverse and forward planning in high-dose-rate interstitial breast implants. Material and methods: By using a representative breast implant, input parameters responsible for target coverage and dose homogeneity were changed step-by-step, and their optimal values were determined. Then, effects of parameters on dosimetry of normal tissue and organs at risk were investigated. The role of dwell time modulation restriction was also studied. With optimal input parameters, treatment plans of forty-two patients were recalculated using an inverse optimization algorithm (HIPO). Then, a pair-wise comparison between forward and inverse plans was performed using dose-volume parameters. Results: To find a compromise between target coverage and dose homogeneity, we recommend using weight factors in the range of 70-90 for minimum dose, and in the range of 10-30 for maximum dose. Maximum dose value of 120% with a weight factor of 5 is recommended for normal tissue. Dose constraints for organs at risk did not play an important role, and the dwell time gradient restriction had only minor effect on target dosimetry. In clinical treatment plans, at identical target coverage, the inverse planning significantly increased the dose conformality (COIN, 0.75 vs. 0.69, p < 0.0001) and improved the homogeneity (DNR, 0.35 vs. 0.39, p = 0.0027), as compared to forward planning. All dosimetric parameters for non-target breast, ipsilateral lung, ribs, and heart were significantly better with inverse planning. The most exposed small volumes for skin were less in HIPO plans, but without statistical significance. Volume irradiated by 5% was 173.5 cm 3 in forward and 167.7 cm 3 in inverse plans (p = 0.0247). Conclusions: By using appropriate input parameters, inverse planning can provide dosimetrically superior dose distributions over forward planning in interstitial breast implants.

show abstract

“…Since in adjuvant vaginal cuff BT following hysterectomy, as a routine, it is recommended that the proximal 3-5 cm of the vagina be treated [20], the selected diode arrangement would be appropriate to cover the clinically significant region. A phantom of 160 x 220 x 160 mm 3 was fabricated using polymethylmethacrylate (PMMA) to surround the applicator without any air gaps and ensure adequate scattering conditions. A picture of the experimental setup used to perform all measurements of this study is shown in figure 1.…”

Section: Mvc Prototype Descriptionmentioning

confidence: 99%

“…It has shown reductions in doses received by organs-at-risk, as compared to the single channel vaginal cylinder (SVC) applicator, without compromising the dose to the target. In fact, as compared to SVC the MVC geometry provides more degrees of freedom (i.e., the source is also dwelling in peripheral channels) to optimize the dose distribution for each patient [1][2][3][4][5].…”

Section: Introductionmentioning

confidence: 99%