Dataset Information

Dosimetric outcomes of preoperative treatment planning with intraoperative optimization using stranded seeds in prostate brachytherapy.

ABSTRACT: This study aimed to evaluate the quality of low-dose-rate (LDR) prostate brachytherapy (BT) based on treatment-related dosimetric outcomes. Data of 100 patients treated using LDR BT with stranded seeds from November 2012 to November 2017 were collected. The prescription dose for the prostate was 145 Gy. The dose constraints for the preoperative plan were: V100% ≥ 95%, V150% ≤ 60%, V200% ≤ 20% for the prostate; V100% for rectum, ≤ 1 cc; and V200 Gy for urethra, 0.0 cc. Intraoperative real-time dose calculation and postoperative dose distribution analysis on days 0 and 30 were performed. Median dosimetric outcomes on days 0 and 30 respective were: V100% 92.28% and 92.23%, V200% 18.63% and 25.02%, and D90% 150.88 Gy and 151.46 Gy for the prostate; V100% for the rectum, 0.11 cc and 0.22 cc; and V200 Gy for the urethra, 0.00 cc and 0.00 cc, respectively. Twenty patients underwent additional seed implantation to compensate for insufficient dose coverage of the prostate. No loss or substantial migration of seeds or severe toxicity was reported. With stranded seed implantation and intraoperative optimization, appropriate dose delivery to the prostate without excessive dose to the organs at risk could be achieved.

SUBMITTER: Lee JJB

PROVIDER: S-EPMC8967021 | biostudies-literature | 2022

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Dosimetric outcomes of preoperative treatment planning with intraoperative optimization using stranded seeds in prostate brachytherapy.

Lee Jason Joon Bock JJB Lee Eungman E Choi Won Hoon WH Kim Jihun J Chang Kyung Hwan KH Kim Dong Wook DW Shin Han Back HB Kim Tae Hyung TH Byun Hwa Kyung HK Cho Jaeho J Cho Jaeho J

PloS one 20220330 3

This study aimed to evaluate the quality of low-dose-rate (LDR) prostate brachytherapy (BT) based on treatment-related dosimetric outcomes. Data of 100 patients treated using LDR BT with stranded seeds from November 2012 to November 2017 were collected. The prescription dose for the prostate was 145 Gy. The dose constraints for the preoperative plan were: V100% ≥ 95%, V150% ≤ 60%, V200% ≤ 20% for the prostate; V100% for rectum, ≤ 1 cc; and V200 Gy for urethra, 0.0 cc. Intraoperative real-time do ...[more]

PMID: 35353847

Similar Datasets

Project description:PurposeBi-objective simultaneous optimization of catheter positions and dwell times for high-dose-rate (HDR) prostate brachytherapy, based directly on dose-volume indices, has shown promising results. However, optimization with the state-of-the-art evolutionary algorithm MO-RV-GOMEA so far required several hours of runtime, and resulting catheter positions were not always clinically feasible. The aim of this study is to extend the optimization model and apply GPU parallelization to achieve clinically acceptable computation times. The resulting optimization procedure is compared with a previously introduced method based solely on geometric criteria, the adapted Centroidal Voronoi Tessellations (CVT) algorithm.MethodsBi-objective simultaneous optimization was performed with a GPU-parallelized version of MO-RV-GOMEA. This optimization of catheter positions and dwell times was retrospectively applied to the data of 26 patients previously treated with HDR prostate brachytherapy for 8-16 catheters (steps of 2). Optimization of catheter positions using CVT was performed in seconds, after which optimization of only the dwell times using MO-RV-GOMEA was performed in 1 min.ResultsSimultaneous optimization of catheter positions and dwell times using MO-RV-GOMEA was performed in 5 min. For 16 down to 8 catheters (steps of 2), MO-RV-GOMEA found plans satisfying the planning-aims for 20, 20, 18, 14, and 11 out of the 26 patients, respectively. CVT achieved this for 19, 17, 13, 9, and 2 patients, respectively. The P-value for the difference between MO-RV-GOMEA and CVT was 0.023 for 16 catheters, 0.005 for 14 catheters, and <0.001 for 12, 10, and 8 catheters.ConclusionsWith bi-objective simultaneous optimization on a GPU, high-quality catheter positions can now be obtained within 5 min, which is clinically acceptable, but slower than CVT. For 16 catheters, the difference between MO-RV-GOMEA and CVT is clinically irrelevant. For 14 catheters and less, MO-RV-GOMEA outperforms CVT in finding plans satisfying all planning-aims.

Project description:MIM Symphony is a recently introduced low-dose-rate prostate brachytherapy treatment planning system (TPS). We evaluated the dosimetric and planning accuracy of this new TPS compared to the universally used VariSeed TPS. For dosimetric evaluation of the MIM Symphony version 5.4 TPS, we compared dose calculations from the MIM Symphony TPS with the formalism recommended by the American Association of Physicists in Medicine Task Group 43 report (TG-43) and those generated by the VariSeed version 8.0 TPS for iodine-125 (I-125; Models 6711 and IAI-125A), palladium-103 (Pd-103; Model 200), and cesium-131 (Cs-131; Model Cs-1). Validation was performed for both line source and point source approximations. As part of the treatment planning validation, first a QA phantom (CIRS Brachytherapy QA Phantom Model 045 SN#D7210-3) containing three ellipsoid objects with certified volumes was scanned in order to check the volume accuracy of the contoured structures in MIM Symphony. Then the DICOM data containing 100 patient plans from the VariSeed TPS were imported into the MIM Symphony TPS. The 100 plans included 25 each of I-125 pre-implant plans, Pd-103 pre-implant plans, I-125 Day 30 plans (i.e., from 1 month after implantation), and Pd-103 Day 30 plans. The dosimetric parameters (including prostate volume, prostate D90 values, and rectum V100 values) of the 100 plans were calculated independently on the two TPSs. Other TPS tests that were done included verification of source input and geometrical accuracy, data transfer between different planning systems, text printout, 2D dose plots, DVH printout, and template grid accuracy. According to the line source formalism, the dosimetric results between the MIM Symphony TPS and TG-43 were within 0.5% (0.02 Gy) for r > 1 cm. In the line source approximation validation, MIM Symphony TPS values agreed with VariSeed TPS values to within 0.5% (0.09 Gy) for r > 1 cm. Similarly, in point source approximation validation, the MIM Symphony values agreed to within 1% of the TG-43 and VariSeed values for r > 1 cm. The volume calculations obtained from the MIM Symphony TPS for the CIRS Brachytherapy QA Phantom were within 1% of the actual volume of the phantom. For the clinical cases, the volume and dosimetric parameter calculations for the prostate and rectum did not differ substantially between the pre-implant and Day 30 plans. Overall, our investigations showed negligible differences in dosimetry calculations and planning parameters between the two TPSs. The tests done to check the performance of the MIM Symphony TPS, such as the library data, data transfer, isodose and DVH printout, were found to be satisfactory. On the basis of these results, we conclude that the MIM Symphony TPS can be used as an alternative to the VariSeed TPS for low-dose-rate prostate brachytherapy.

Project description:BackgroundBlood pressure variability (BPV) describes visit-to-visit blood pressure (BP) changes independent of hypertension. Preoperative BPV and intraoperative BPV are associated with increased postoperative outcomes. We investigated the impact of both preoperative BPV and intraoperative BPV on elective surgical outcomes, specifically whether preoperative BPV and intraoperative BPV were independent risk factors for surgical complications.Materials and methodsWe investigated 600 patients undergoing elective surgery lasting more than two h and who had ≥8 outpatient BP recordings over three preoperative years. Age, sex, ethnicity, BMI, current medical problems, and medications at time of surgery were recorded. BPV was calculated as the standard deviation (SD) of systolic or diastolic BP for the 369 valid patients. Average BPV were compared between adverse outcomes of readmission, wound infection, acute kidney injury, death, myocardial infarction, and cerebral vascular accident.ResultsThree-hundred-sixty-nine (52.6% male, 47.4% female, 98.1% non-Hispanic) patients (mean age 62.5) were included in the study. Preoperative systolic (P = 0.043) and diastolic (P = 0.009) BPV were higher for patients with the combined endpoint of all adverse events. Preoperative systolic BPV was correlated with intraoperative BPV (P = 0.010). Both systolic and diastolic preoperative BPV was found to be independent from intraoperative BPV. Otolaryngology procedures were associated with less adverse outcomes (P = 0.034), whil antimicrobials (P = 0.022), autonomic drugs (P < 0.001), or respiratory drugs (P = 0.032) was associated with an increased likelihood of adverse outcome.ConclusionPreoperative DBPV is associated with increased risk of readmission, wound infection and the combined endpoint of all adverse events. Intraoperative systolic blood pressure variability (SPBV) is associated with increased risk of acute kidney injury and the combined endpoint of all adverse events. Preoperative DBPV and intraoperative SBPV are independent risk factors for ninety-d postoperative outcomes. BPV should be considered in individualized risk assessment when assessing patient eligibility for elective procedures.

Project description:Purpose: This study aims to investigate the prognostic value and dosimetric impact of paranasal sinus invasion (PSI) in patients with nasopharyngeal carcinoma (NPC), and further to explore the feasibility of an integrative prognostic model based on anatomic, volumetric, and dosimetric features. Methods: Two hundred six patients with T3 NPC receiving intensity-modulated radiation therapy (IMRT) were retrospectively analyzed. Dosimetric parameters were calculated from dose-volume histograms. Primary gross tumor volume (GTV-P) and dosimetric parameters were categorized using optimal cutpoints determined by R. Local recurrence-free survival (LRFS) was estimated using Kaplan-Meier method. Independent risk factors for LRFS were identified through univariable and multivariable analyses by Cox proportional hazards models. Results: The incidence of PSI was 10.7% (22/206). Patients with PSI had significantly inferior 5-year LRFS (77.3 vs. 93.8%, P = 0.006). IMRT plans for patients with PSI had larger dose heterogeneity, higher frequency of underdosing, and higher maximum dose to optic structures. When categorized by optimal cutpoints, GTV-P > 38.67 cm3 (5-year LRFS, 84.8 vs. 97.4%, P = 0.008), and V66.88 < 89.87% (5-year LRFS, 67.1 vs. 94.5%, P < 0.001) were associated with significantly worse local outcome. Multivariable analyses showed that PSI, GTV-P > 38.67 cm3, and V66.88 < 89.87% were independent risk factors for local relapse, either in patients with or without concurrent chemotherapy. An integrative prognostic model was then established upon the cumulative score of risk factors. Subgroups with score of 0, 1-2, and 3 had distinctive local outcomes; the 5-year LRFS was 96.6, 84.7, and 58.3%, respectively (P < 0.001). Conclusions: Paranasal sinus invasion jeopardized local control in T3 NPC patients due to large tumor burden and inadequate radiation dose in GTV-P. The presence of PSI, GTV-P, and radiation underdosing combined are critical for the risk stratification of local failure.

Dataset Information

Dosimetric outcomes of preoperative treatment planning with intraoperative optimization using stranded seeds in prostate brachytherapy.

Publications

Dosimetric outcomes of preoperative treatment planning with intraoperative optimization using stranded seeds in prostate brachytherapy.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets