Pub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.148
Magdalena Anna Stankiewicz
Purpose High-dose-rate (HDR) brachytherapy is a vital part of treatment in patients with locally advanced cervical cancer. Current guidelines recommend the use of image-guided adaptive brachytherapy (IGABT). Several fractionation schedules are used in external beam radiotherapy (EBRT) and brachytherapy (BT). A retrospective analysis of patients treated with radio(chemo)therapy and HDR brachytherapy due to cervical cancer was conducted. We compared the efficacy of two fractionation schedules implemented in our department. Materials and Methods Schedule one ("5x6 Gy") consisted of five fractions of 6 Gy delivered within 2.5 weeks. In the majority of patients, the dose was prescribed to point A. Schedule two ("4x7 Gy") consisted of four fractions of 7 Gy delivered within two weeks. In all patients, the dose was prescribed to CTV. Local control (LC) and distant metastasis-free survival (DMFS) were calculated. The Kaplan-Meier estimator, log-rank and Mann-Whitney U test were used in statistical analysis. One hundred seventeen patients were included in this analysis. Median age was 57 years (range: 29 - 79). The disease stage was re-assessed according to FIGO 2018 classification. Forty-five percent of patients had FIGO IIIC1 disease, 29% - FIGO IIIB, 15% - FIGO IIB and 6% - FIGO IIIC2. The vast majority of patients (96%) had were diagnosed with planoepithelial carcinoma, 2,5% with cervical adenocarcinoma, one patient with clear cell carcinoma and one with serous carcinoma. The "5x6 Gy" fractionation was administered in 79% of patients. The median overall treatment time (OTT) was 58 days (range: 45 - 139 days). The median CTV D90 EQD2 sum of EBRT and BT was 89 Gy (range: 65 - 114 Gy). Results In the "5x6 Gy" subgroup, the follow-up was significantly longer (p=0.00006), CTV D90 EQD2 was significantly higher (p=0.0001), and OTT was significantly longer (p=0.02). No other significant differences were observed between the subgroups. They were well balanced in terms of patients' age (p=0.6), histopathological grade of the tumour (p=0.2) and FIGO stage (p=0.07). In the whole group, 5-year LC was 91%, 5-year regional nodal control was 86%, and 5-year DMFS was 80%. The comparison of the two fractionation schedules ("5x6 Gy" vs "4x7 Gy") revealed that higher CTV D90 EQD2 was not associated with better local or distant control. There were no differences in LC (p=0.79), regional nodal control (p=0.7) or DMFS (p=0.83) between the subgroups. However, better regional nodal control and longer DMFS were observed in patients with OTT≤60 days (p=0.035 and p=0.017, respectively). Conclusions Both fractionation schedules have similar efficacy. A shorter overall treatment time is associated with better regional nodal control and DMFS. However, a longer follow-up is needed to confirm these findings. High-dose-rate (HDR) brachytherapy is a vital part of treatment in patients with locally advanced cervical cancer. Current guidelines recommend the use of image-guided adaptive b
{"title":"PO47","authors":"Magdalena Anna Stankiewicz","doi":"10.1016/j.brachy.2023.06.148","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.148","url":null,"abstract":"Purpose High-dose-rate (HDR) brachytherapy is a vital part of treatment in patients with locally advanced cervical cancer. Current guidelines recommend the use of image-guided adaptive brachytherapy (IGABT). Several fractionation schedules are used in external beam radiotherapy (EBRT) and brachytherapy (BT). A retrospective analysis of patients treated with radio(chemo)therapy and HDR brachytherapy due to cervical cancer was conducted. We compared the efficacy of two fractionation schedules implemented in our department. Materials and Methods Schedule one (\"5x6 Gy\") consisted of five fractions of 6 Gy delivered within 2.5 weeks. In the majority of patients, the dose was prescribed to point A. Schedule two (\"4x7 Gy\") consisted of four fractions of 7 Gy delivered within two weeks. In all patients, the dose was prescribed to CTV. Local control (LC) and distant metastasis-free survival (DMFS) were calculated. The Kaplan-Meier estimator, log-rank and Mann-Whitney U test were used in statistical analysis. One hundred seventeen patients were included in this analysis. Median age was 57 years (range: 29 - 79). The disease stage was re-assessed according to FIGO 2018 classification. Forty-five percent of patients had FIGO IIIC1 disease, 29% - FIGO IIIB, 15% - FIGO IIB and 6% - FIGO IIIC2. The vast majority of patients (96%) had were diagnosed with planoepithelial carcinoma, 2,5% with cervical adenocarcinoma, one patient with clear cell carcinoma and one with serous carcinoma. The \"5x6 Gy\" fractionation was administered in 79% of patients. The median overall treatment time (OTT) was 58 days (range: 45 - 139 days). The median CTV D90 EQD2 sum of EBRT and BT was 89 Gy (range: 65 - 114 Gy). Results In the \"5x6 Gy\" subgroup, the follow-up was significantly longer (p=0.00006), CTV D90 EQD2 was significantly higher (p=0.0001), and OTT was significantly longer (p=0.02). No other significant differences were observed between the subgroups. They were well balanced in terms of patients' age (p=0.6), histopathological grade of the tumour (p=0.2) and FIGO stage (p=0.07). In the whole group, 5-year LC was 91%, 5-year regional nodal control was 86%, and 5-year DMFS was 80%. The comparison of the two fractionation schedules (\"5x6 Gy\" vs \"4x7 Gy\") revealed that higher CTV D90 EQD2 was not associated with better local or distant control. There were no differences in LC (p=0.79), regional nodal control (p=0.7) or DMFS (p=0.83) between the subgroups. However, better regional nodal control and longer DMFS were observed in patients with OTT≤60 days (p=0.035 and p=0.017, respectively). Conclusions Both fractionation schedules have similar efficacy. A shorter overall treatment time is associated with better regional nodal control and DMFS. However, a longer follow-up is needed to confirm these findings. High-dose-rate (HDR) brachytherapy is a vital part of treatment in patients with locally advanced cervical cancer. Current guidelines recommend the use of image-guided adaptive b","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.130
Firas Mourtada, Ayesha Ali, Wookjin Choi, Rani Anne, Wayne Pinover, Beth Erickson, Ann Klopp, Daniel Petereit, David Gaffney, Emma Fields, Junzo Chino, Catheryn Yashar, Mitchell Kamrava, Marisa Kollmeier, Reza Taleei, Shuying Wan, Yevgeniy Vinogradskiy
A novel mobile cone-beam computed tomography (CBCT) imaging device (Elekta Inc.) aims to improve efficiency with on-demand imaging in the HDR vault during and after applicator insertion. We evaluated whether inter-observer contour variability of standard organs-at-risk (OARs) was similar using this novel CBCT (Ring-CBCT) as compared to diagnostic-quality simulation CT (CT-Sim) for cervical cancer HDR brachytherapy. A patient with stage IIB cervical cancer was implanted with the CT/MR Venezia Tandem (6-cm, 30-deg) with 26-mm dia. Lunar Ovoids. Images were acquired with Ring-CBCT (Elekta ImagingRing v 2.5.2) using 120 kVp, 8 mA, and 0.6x0.6x1.2 mm voxel size, and CT-Sim (Siemens SOMATOM go.Open Pro) using department standard pelvis imaging protocol (120 kVp, 1.17x1.17x1 mm voxel size, 0.8 pitch). Zypher transfer system (Orfit Inc.) was used to move patient to reduce applicator motion. Bladder, rectum, sigmoid, and lower bowel were independently contoured by 11 brachytherapists on Ring-CBCT and CT-Sim in Oncentra TPS. After each session, the physician answered a survey with a score from 1-10 for a qualitative evaluation of their comfort level for each contour. Inter-observer contour variability was quantitatively evaluated using Average Surface Distance, 95% Housdorff Distance, 100% Housdorff Distance, Surface Overlap, Surface Dice, and Volumetric Dice comparisons between a reference contour (RA) and each physician's contour. Wilcoxon signed-rank test was applied to test the statistical difference between the metrics on CT-sim and Ring-CBCT. Eleven physicians completed all four OAR contours on both imaging modalities and completed all surveys. The questionnaire results revealed there was greater confidence in the CT contours when compared to the Ring-CBCT contours. Comfort levels were a median of 10 (9-10) vs. 8 (6-10 (p<0.01) for bladder, 9 (8-10) vs. 8 (4-10) (p<0.01) for rectum, 8.5 (8-10) vs. 6.5 (2-10) (p<0.001) for sigmoid and 8 (7-10) vs. 5 (1-10) (p<0.001) for bowel, respectively. Inter-observer variations in OAR delineation on CT-sim and Ring CBCT are shown in Table 1. Overall, CT-sim showed lower interobserver variation when compared to the Ring-CBCT. There were no statistically significant differences between contour variability with Ring-CBCT when compared to contour variability assessed with CT-sim for most OARs and metrics evaluated. Bladder showed the most prevalent statistically significant variability differences between CT-Sim and Ring-CBCT as evaluated by surface metrics (Average Surface Distance and Hausdorff Distance). Using a multi-center approach and a comprehensive suite of comparison metrics, this study provides the first report of image quality assessment of a novel Ring CBCT for HDR applications. Our data show that for the presented patient, the contours generated using the Ring-CBCT show similar variability when compared to contours generated using standard of care CT-Sim imaging. Based on the physician survey however, OA
{"title":"PO29","authors":"Firas Mourtada, Ayesha Ali, Wookjin Choi, Rani Anne, Wayne Pinover, Beth Erickson, Ann Klopp, Daniel Petereit, David Gaffney, Emma Fields, Junzo Chino, Catheryn Yashar, Mitchell Kamrava, Marisa Kollmeier, Reza Taleei, Shuying Wan, Yevgeniy Vinogradskiy","doi":"10.1016/j.brachy.2023.06.130","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.130","url":null,"abstract":"A novel mobile cone-beam computed tomography (CBCT) imaging device (Elekta Inc.) aims to improve efficiency with on-demand imaging in the HDR vault during and after applicator insertion. We evaluated whether inter-observer contour variability of standard organs-at-risk (OARs) was similar using this novel CBCT (Ring-CBCT) as compared to diagnostic-quality simulation CT (CT-Sim) for cervical cancer HDR brachytherapy. A patient with stage IIB cervical cancer was implanted with the CT/MR Venezia Tandem (6-cm, 30-deg) with 26-mm dia. Lunar Ovoids. Images were acquired with Ring-CBCT (Elekta ImagingRing v 2.5.2) using 120 kVp, 8 mA, and 0.6x0.6x1.2 mm voxel size, and CT-Sim (Siemens SOMATOM go.Open Pro) using department standard pelvis imaging protocol (120 kVp, 1.17x1.17x1 mm voxel size, 0.8 pitch). Zypher transfer system (Orfit Inc.) was used to move patient to reduce applicator motion. Bladder, rectum, sigmoid, and lower bowel were independently contoured by 11 brachytherapists on Ring-CBCT and CT-Sim in Oncentra TPS. After each session, the physician answered a survey with a score from 1-10 for a qualitative evaluation of their comfort level for each contour. Inter-observer contour variability was quantitatively evaluated using Average Surface Distance, 95% Housdorff Distance, 100% Housdorff Distance, Surface Overlap, Surface Dice, and Volumetric Dice comparisons between a reference contour (RA) and each physician's contour. Wilcoxon signed-rank test was applied to test the statistical difference between the metrics on CT-sim and Ring-CBCT. Eleven physicians completed all four OAR contours on both imaging modalities and completed all surveys. The questionnaire results revealed there was greater confidence in the CT contours when compared to the Ring-CBCT contours. Comfort levels were a median of 10 (9-10) vs. 8 (6-10 (p<0.01) for bladder, 9 (8-10) vs. 8 (4-10) (p<0.01) for rectum, 8.5 (8-10) vs. 6.5 (2-10) (p<0.001) for sigmoid and 8 (7-10) vs. 5 (1-10) (p<0.001) for bowel, respectively. Inter-observer variations in OAR delineation on CT-sim and Ring CBCT are shown in Table 1. Overall, CT-sim showed lower interobserver variation when compared to the Ring-CBCT. There were no statistically significant differences between contour variability with Ring-CBCT when compared to contour variability assessed with CT-sim for most OARs and metrics evaluated. Bladder showed the most prevalent statistically significant variability differences between CT-Sim and Ring-CBCT as evaluated by surface metrics (Average Surface Distance and Hausdorff Distance). Using a multi-center approach and a comprehensive suite of comparison metrics, this study provides the first report of image quality assessment of a novel Ring CBCT for HDR applications. Our data show that for the presented patient, the contours generated using the Ring-CBCT show similar variability when compared to contours generated using standard of care CT-Sim imaging. Based on the physician survey however, OA","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.122
Alvin Kumar, Avtar Raina
Brachytherapy (BT) has been utilized for the treatment of anal cancer for many decades. A previous systematic review had shown benefit of BT boost in patients undergoing curative intent chemo-radiotherapy for anal canal cancer. Despite this, the use of BT boost is still restricted to a few chosen institutions and is typically not mentioned as a therapeutic alternative in the well-known international standards. Barriers to its widespread implementation have been identified as specialised knowledge, complexity, and equipment. There is also not much evidence in literature regarding the use of BT as a sole modality for treating early stage anal cancers. Christchurch Oncology has 12 years’ of clinical experience with High Dose rate intracavitary/ interstitial brachytherapy for Gynaecological and Prostate cancers, however this is our first experience of treating anal cancer with brachytherapy. We present a case study of a patient with localised primary anal cancer that was referred to our department to determine if brachytherapy would be an option. This 80yr old fit/independent female had adjuvant pelvic radiation treatment for a cervical cancer (Stage 1B) SCC in 1981 receiving a dose of 45Gy/20#. She was recently diagnosed with SCC of Anal Canal (cT1 N0) and further curative external beam radiation was deemed too high risk in terms of toxicities and morbidities and patient was reluctant to accept abdominoperineal resection for reasons relating to quality of life when dealing with a permanent stoma. Even though there is not much evidence for using brachytherapy as a sole modality for curative treatment for anal cancer, given the limited treatment options available, this would not be an unreasonable approach. Staging Colonoscopy, FDG PET CT scan, and MRI highlighted a superficial tumour that extended a total of 16mm from proximal anal canal to mid anal canal from 12-7 o'clock position without invasion or lymphadenopathy. A pre-BT MRI was performed with the Nucletron Multichannel applicator (MCA) in situ. The plan was optimised in Oncentra Brachy (OCB) V4.6.2 using a combination of central channel and superficial channels. A prescription dose of 33Gy/6# was chosen and the final dose coverage of the targets are listed below: Dose reporting for targets: Dose per fraction / Dose per treatment EQD2Gy (a/b =10) HRCTV: D90= 5.8Gy/ 45.4Gy D100= 5.3Gy / 41.0Gy IRCTV: D90= 4.8Gy / 35.6Gy D100= 4.2Gy / 29.9Gy Following completion of BT, patient developed radiation dermatitis with some soreness around the perianal area that was treated with local suppositories and hydrocortisone cream. At 3 and 6 months follow-up, there was no signs of active dermatitis or any bowel incontinence Brachytherapy (BT) has been utilized for the treatment of anal cancer for many decades. A previous systematic review had shown benefit of BT boost in patients undergoing curative intent chemo-radiotherapy for anal canal cancer. Despite this, the use of BT boost is still restricted to a few
{"title":"PO21","authors":"Alvin Kumar, Avtar Raina","doi":"10.1016/j.brachy.2023.06.122","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.122","url":null,"abstract":"Brachytherapy (BT) has been utilized for the treatment of anal cancer for many decades. A previous systematic review had shown benefit of BT boost in patients undergoing curative intent chemo-radiotherapy for anal canal cancer. Despite this, the use of BT boost is still restricted to a few chosen institutions and is typically not mentioned as a therapeutic alternative in the well-known international standards. Barriers to its widespread implementation have been identified as specialised knowledge, complexity, and equipment. There is also not much evidence in literature regarding the use of BT as a sole modality for treating early stage anal cancers. Christchurch Oncology has 12 years’ of clinical experience with High Dose rate intracavitary/ interstitial brachytherapy for Gynaecological and Prostate cancers, however this is our first experience of treating anal cancer with brachytherapy. We present a case study of a patient with localised primary anal cancer that was referred to our department to determine if brachytherapy would be an option. This 80yr old fit/independent female had adjuvant pelvic radiation treatment for a cervical cancer (Stage 1B) SCC in 1981 receiving a dose of 45Gy/20#. She was recently diagnosed with SCC of Anal Canal (cT1 N0) and further curative external beam radiation was deemed too high risk in terms of toxicities and morbidities and patient was reluctant to accept abdominoperineal resection for reasons relating to quality of life when dealing with a permanent stoma. Even though there is not much evidence for using brachytherapy as a sole modality for curative treatment for anal cancer, given the limited treatment options available, this would not be an unreasonable approach. Staging Colonoscopy, FDG PET CT scan, and MRI highlighted a superficial tumour that extended a total of 16mm from proximal anal canal to mid anal canal from 12-7 o'clock position without invasion or lymphadenopathy. A pre-BT MRI was performed with the Nucletron Multichannel applicator (MCA) in situ. The plan was optimised in Oncentra Brachy (OCB) V4.6.2 using a combination of central channel and superficial channels. A prescription dose of 33Gy/6# was chosen and the final dose coverage of the targets are listed below: Dose reporting for targets: Dose per fraction / Dose per treatment EQD2Gy (a/b =10) HRCTV: D90= 5.8Gy/ 45.4Gy D100= 5.3Gy / 41.0Gy IRCTV: D90= 4.8Gy / 35.6Gy D100= 4.2Gy / 29.9Gy Following completion of BT, patient developed radiation dermatitis with some soreness around the perianal area that was treated with local suppositories and hydrocortisone cream. At 3 and 6 months follow-up, there was no signs of active dermatitis or any bowel incontinence Brachytherapy (BT) has been utilized for the treatment of anal cancer for many decades. A previous systematic review had shown benefit of BT boost in patients undergoing curative intent chemo-radiotherapy for anal canal cancer. Despite this, the use of BT boost is still restricted to a few ","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Purpose To commission and retrospectively compare dosimetry of Elekta's Advanced Collapsed Cone Engine (ACE) calculation algorithm with the standard TG 43-based dose formalism on an IPSA-optimized and CT-based HDR clinical breast plan. Materials and Methods At our institution, we commissioned ACE for HDR brachytherapy using the “Breast Test Case” data from iroc.mdandderson.org. This used a generic Ir-192 source and was published by the AAPM Working Group on Commissioning of Model-Based Dose Calculation Algorithms in Brachytherapy (UN35). A previous breast cancer case treated with Hologic's Contura multi-catheter HDR applicator was selected from our clinical database to evaluate the ACE dose engine. The Oncentra treatment planning system (v. 4.6) was used in this study. The HDR plan was first calculated with the TG-43 dose formalism and optimized using inverse planning by a simulated annealing algorithm (IPSA). Using the same relative dwell weights provided by IPSA from the TG-43 plan, dose was then recalculated using the ACE algorithm. The ACE calculation used Oncentra's High Accuracy level with a 1.0-mm-cubed dose grid. The planning target volume (PTV) and organs at risk (including regions with significant inhomogeneity) were contoured. Dose Volume Histograms (DVH's) of the PTV_eval and organs at risk were calculated with both TG-43 and ACE dose formalisms for each plan. Absolute and percent differences were also calculated for each metric. Results As shown in Table 1, the ACE calculated dose relative to the TG-43 calculated dose is consistently lower for all dosimetric parameters. The dose calculation differed by up to 9% or 112 cGy in the selected parameters. See comparison table for more details. The calculation time was 16 minutes using the standard GPU provided by Elekta hardware. Conclusion The IROC “Breast Test Case” ACE commissioning was a straightforward procedure and easy installation. Total commissioning time was less than an hour. The ACE calculated dose relative to the TG-43 calculated dose in the selected patient case was consistently lower for all dosimetric parameters. This algorithm offers a more accurate reconstruction of the dose distribution (by comparison to Monte Carlo, per UN35). The highest percent differences in dose calculation were found in the PTV_eval and skin region for this case. This study provides a framework for future studies of ACE dosimetric impact for breast cancer brachytherapy, and more breast cancer patient plans will be analyzed with summary statistics reported. This will be a particularly useful framework when correlating lower skin dose estimate with cosmetic outcomes. To commission and retrospectively compare dosimetry of Elekta's Advanced Collapsed Cone Engine (ACE) calculation algorithm with the standard TG 43-based dose formalism on an IPSA-optimized and CT-based HDR clinical breast plan. At our institution, we commissioned ACE for HDR brachytherapy using the “Breast Test Case” data from iroc.mdand
{"title":"PO91","authors":"Sophia Rooks, Reza Taleei, Nicole Simone, P. Rani Anne, Firas Mourtada","doi":"10.1016/j.brachy.2023.06.192","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.192","url":null,"abstract":"Purpose To commission and retrospectively compare dosimetry of Elekta's Advanced Collapsed Cone Engine (ACE) calculation algorithm with the standard TG 43-based dose formalism on an IPSA-optimized and CT-based HDR clinical breast plan. Materials and Methods At our institution, we commissioned ACE for HDR brachytherapy using the “Breast Test Case” data from iroc.mdandderson.org. This used a generic Ir-192 source and was published by the AAPM Working Group on Commissioning of Model-Based Dose Calculation Algorithms in Brachytherapy (UN35). A previous breast cancer case treated with Hologic's Contura multi-catheter HDR applicator was selected from our clinical database to evaluate the ACE dose engine. The Oncentra treatment planning system (v. 4.6) was used in this study. The HDR plan was first calculated with the TG-43 dose formalism and optimized using inverse planning by a simulated annealing algorithm (IPSA). Using the same relative dwell weights provided by IPSA from the TG-43 plan, dose was then recalculated using the ACE algorithm. The ACE calculation used Oncentra's High Accuracy level with a 1.0-mm-cubed dose grid. The planning target volume (PTV) and organs at risk (including regions with significant inhomogeneity) were contoured. Dose Volume Histograms (DVH's) of the PTV_eval and organs at risk were calculated with both TG-43 and ACE dose formalisms for each plan. Absolute and percent differences were also calculated for each metric. Results As shown in Table 1, the ACE calculated dose relative to the TG-43 calculated dose is consistently lower for all dosimetric parameters. The dose calculation differed by up to 9% or 112 cGy in the selected parameters. See comparison table for more details. The calculation time was 16 minutes using the standard GPU provided by Elekta hardware. Conclusion The IROC “Breast Test Case” ACE commissioning was a straightforward procedure and easy installation. Total commissioning time was less than an hour. The ACE calculated dose relative to the TG-43 calculated dose in the selected patient case was consistently lower for all dosimetric parameters. This algorithm offers a more accurate reconstruction of the dose distribution (by comparison to Monte Carlo, per UN35). The highest percent differences in dose calculation were found in the PTV_eval and skin region for this case. This study provides a framework for future studies of ACE dosimetric impact for breast cancer brachytherapy, and more breast cancer patient plans will be analyzed with summary statistics reported. This will be a particularly useful framework when correlating lower skin dose estimate with cosmetic outcomes. To commission and retrospectively compare dosimetry of Elekta's Advanced Collapsed Cone Engine (ACE) calculation algorithm with the standard TG 43-based dose formalism on an IPSA-optimized and CT-based HDR clinical breast plan. At our institution, we commissioned ACE for HDR brachytherapy using the “Breast Test Case” data from iroc.mdand","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.165
Shyamal Patel, Dilini Pinnaduwage, Nitika Thawani, Stephen Sorensen, Shyam Jani, Steven Ellefson, Aidnag Diaz, Shiv Srivastava
Purpose When utilizing a hydrogel spacer for HDR prostate brachytherapy, hydrogel can be inserted at time of HDR catheter implantation or on a separate visit prior to HDR. The insertion of gel at time of HDR can be more difficult due to interference from the perineal template with imbedded catheters. To assess whether time of hydrogel placement impacted its insertion geometry, we compared patients who had hydrogel placed by a single provider at either the time of HDR brachytherapy (templated insertion - TI) or in advance of prostate stereotactic body radiation therapy (non-templated insertion - NTI). The ultimate aim of this study was to determine whether patients undergoing HDR should have hydrogel placed prior to catheter implantation for improved rectal dosimetry. Materials and Methods The last consecutive 25 patients treated with HDR brachytherapy with hydrogel (TI) and the last consecutive 25 patients treated with prostate SBRT with hydrogel (NTI) in 2022 were included for analysis. CT planning scans for all patients were reviewed and insertion geometry was recorded as represented by measurements of the anteroposterior rectoprostatic separation at the gland apex, mid, and base. Prostate clinical target volume (CTV) measurements for all patients were recorded. Additionally, rectal D0.1cc, D1cc, and D2cc measurements were also noted for the 25 HDR TI patients. Data were analyzed using a one-way MANOVA to determine significance of templated insertion. Subsequently multiple regression analyses were performed to evaluate the impact of insertion geometry and CTV measurements on rectal dosimetry. Results The differences in AP separations between TI and NTI were nonsignificant. The mean TI and NTI separations (cm) were 1.08 vs. 1.18 for apex, p=0.40; 1.40 vs. 1.42 for mid, p=0.84; and 1.52 vs. 1.47 for base, p=0.77. In HDR patients with templated insertion, AP separations at the apex and mid gland were significant in predicting rectal D0.1cc (β -0.49 and -0.51, p<0.001), D1cc (β -0.46 and -0.56, p<0.001) and D2cc (β -0.45 and -0.55, p<0.001). The base separations were not significant. CTVs also did not significantly predict for rectal dosimetry. Conclusions Placement of hydrogel spacer at time of HDR brachytherapy does not appear to adversely affect hydrogel insertion geometry and consequently rectal dosimetry when compared to placement in advance. We will continue our practice of inserting hydrogel at time of HDR brachytherapy as this method is efficient and also more convenient for patients. When utilizing a hydrogel spacer for HDR prostate brachytherapy, hydrogel can be inserted at time of HDR catheter implantation or on a separate visit prior to HDR. The insertion of gel at time of HDR can be more difficult due to interference from the perineal template with imbedded catheters. To assess whether time of hydrogel placement impacted its insertion geometry, we compared patients who had hydrogel placed by a single provider at either the time of HDR
目的:在HDR前列腺近距离治疗中使用水凝胶间隔器时，水凝胶可以在HDR导管植入时插入，也可以在HDR前单独就诊时插入。在HDR时，由于会阴部模板内嵌导管的干扰，凝胶的插入可能会更加困难。为了评估水凝胶放置的时间是否会影响其插入的几何形状，我们比较了在HDR近距离放疗(模板插入- TI)或前列腺立体定向放射治疗(非模板插入- NTI)之前由单一提供者放置水凝胶的患者。本研究的最终目的是确定HDR患者是否应该在导管植入前放置水凝胶以改善直肠剂量学。材料与方法选取2022年最后连续25例HDR近距离水凝胶(TI)治疗患者和最后连续25例前列腺SBRT水凝胶(NTI)治疗患者进行分析。回顾所有患者的CT规划扫描，记录插入几何形状，以测量腺体尖端、中部和基部的前后直肠前列腺分离为代表。记录所有患者的前列腺临床靶体积(CTV)测量值。此外，25例HDR TI患者的直肠D0.1cc、D1cc和D2cc测量也被记录下来。采用单因素方差分析确定模板插入的显著性。随后进行多元回归分析，以评估插入几何形状和CTV测量对直肠剂量学的影响。结果TI与NTI的AP分离量差异无统计学意义。TI和NTI的平均间距(cm)分别为1.08和1.18,p=0.40;1.40 vs. 1.42, p=0.84;基数为1.52 vs 1.47, p=0.77。在模板植入的HDR患者中，顶端和中间腺的AP分离对直肠D0.1cc (β -0.49和-0.51,p<0.001)、D1cc (β -0.46和-0.56,p<0.001)和D2cc (β -0.45和-0.55,p<0.001)具有显著预测意义。碱基分离不显著。ctv也不能显著预测直肠剂量学。结论:与预先放置水凝胶间隔剂相比，在HDR近距离放疗时放置水凝胶间隔剂不会对水凝胶插入的几何形状和直肠剂量测定产生不利影响。我们将继续在HDR近距离治疗时插入水凝胶的做法，因为这种方法效率高，对患者也更方便。当使用水凝胶间隔器进行HDR前列腺近距离治疗时，水凝胶可以在HDR导管植入时插入，也可以在HDR之前的单独访问中插入。在HDR时，由于会阴部模板内嵌导管的干扰，凝胶的插入可能会更加困难。为了评估水凝胶放置的时间是否会影响其插入的几何形状，我们比较了在HDR近距离放疗(模板插入- TI)或前列腺立体定向放射治疗(非模板插入- NTI)之前由单一提供者放置水凝胶的患者。本研究的最终目的是确定HDR患者是否应该在导管植入前放置水凝胶以改善直肠剂量学。纳入2022年最后连续25例水凝胶(TI) HDR近距离放疗患者和最后连续25例水凝胶(NTI)前列腺SBRT患者进行分析。回顾所有患者的CT规划扫描，记录插入几何形状，以测量腺体尖端、中部和基部的前后直肠前列腺分离为代表。记录所有患者的前列腺临床靶体积(CTV)测量值。此外，25例HDR TI患者的直肠D0.1cc、D1cc和D2cc测量也被记录下来。采用单因素方差分析确定模板插入的显著性。随后进行多元回归分析，以评估插入几何形状和CTV测量对直肠剂量学的影响。TI和NTI之间的AP分离差异不显著。TI和NTI的平均间距(cm)分别为1.08和1.18,p=0.40;1.40 vs. 1.42, p=0.84;基数为1.52 vs 1.47, p=0.77。在模板植入的HDR患者中，顶端和中间腺的AP分离对直肠D0.1cc (β -0.49和-0.51,p<0.001)、D1cc (β -0.46和-0.56,p<0.001)和D2cc (β -0.45和-0.55,p<0.001)具有显著预测意义。碱基分离不显著。ctv也不能显著预测直肠剂量学。与预先放置水凝胶间隔剂相比，在HDR近距离放疗时放置水凝胶间隔剂似乎不会对水凝胶插入的几何形状和直肠剂量测定产生不利影响。 我们将继续在HDR近距离治疗时插入水凝胶的做法，因为这种方法效率高，对患者也更方便。 我们将继续在HDR近距离治疗时插入水凝胶的做法，因为这种方法效率高，对患者也更方便。
{"title":"PO64","authors":"Shyamal Patel, Dilini Pinnaduwage, Nitika Thawani, Stephen Sorensen, Shyam Jani, Steven Ellefson, Aidnag Diaz, Shiv Srivastava","doi":"10.1016/j.brachy.2023.06.165","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.165","url":null,"abstract":"Purpose When utilizing a hydrogel spacer for HDR prostate brachytherapy, hydrogel can be inserted at time of HDR catheter implantation or on a separate visit prior to HDR. The insertion of gel at time of HDR can be more difficult due to interference from the perineal template with imbedded catheters. To assess whether time of hydrogel placement impacted its insertion geometry, we compared patients who had hydrogel placed by a single provider at either the time of HDR brachytherapy (templated insertion - TI) or in advance of prostate stereotactic body radiation therapy (non-templated insertion - NTI). The ultimate aim of this study was to determine whether patients undergoing HDR should have hydrogel placed prior to catheter implantation for improved rectal dosimetry. Materials and Methods The last consecutive 25 patients treated with HDR brachytherapy with hydrogel (TI) and the last consecutive 25 patients treated with prostate SBRT with hydrogel (NTI) in 2022 were included for analysis. CT planning scans for all patients were reviewed and insertion geometry was recorded as represented by measurements of the anteroposterior rectoprostatic separation at the gland apex, mid, and base. Prostate clinical target volume (CTV) measurements for all patients were recorded. Additionally, rectal D0.1cc, D1cc, and D2cc measurements were also noted for the 25 HDR TI patients. Data were analyzed using a one-way MANOVA to determine significance of templated insertion. Subsequently multiple regression analyses were performed to evaluate the impact of insertion geometry and CTV measurements on rectal dosimetry. Results The differences in AP separations between TI and NTI were nonsignificant. The mean TI and NTI separations (cm) were 1.08 vs. 1.18 for apex, p=0.40; 1.40 vs. 1.42 for mid, p=0.84; and 1.52 vs. 1.47 for base, p=0.77. In HDR patients with templated insertion, AP separations at the apex and mid gland were significant in predicting rectal D0.1cc (β -0.49 and -0.51, p<0.001), D1cc (β -0.46 and -0.56, p<0.001) and D2cc (β -0.45 and -0.55, p<0.001). The base separations were not significant. CTVs also did not significantly predict for rectal dosimetry. Conclusions Placement of hydrogel spacer at time of HDR brachytherapy does not appear to adversely affect hydrogel insertion geometry and consequently rectal dosimetry when compared to placement in advance. We will continue our practice of inserting hydrogel at time of HDR brachytherapy as this method is efficient and also more convenient for patients. When utilizing a hydrogel spacer for HDR prostate brachytherapy, hydrogel can be inserted at time of HDR catheter implantation or on a separate visit prior to HDR. The insertion of gel at time of HDR can be more difficult due to interference from the perineal template with imbedded catheters. To assess whether time of hydrogel placement impacted its insertion geometry, we compared patients who had hydrogel placed by a single provider at either the time of HDR ","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434417","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.215
Evangelia Kaza, Phillip M. Devlin, Ivan Buzurovic
{"title":"PO114","authors":"Evangelia Kaza, Phillip M. Devlin, Ivan Buzurovic","doi":"10.1016/j.brachy.2023.06.215","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.215","url":null,"abstract":"","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434420","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.161
Kevin Martell, Breanna Fang, Philip McGeachy, Tyler Meyer, Siraj Husain, Kundan Thind
Purpose Isolated intraprostatic recurrence of prostate adenocarcinoma post radiotherapy presents a clinically challenging situation as surgical salvage options are associated with high morbidity. Brachytherapy can be used in these cases but supportive data are limited. The present study aims to present the acute toxicity results from patients who received salvage high-dose-rate prostate brachytherapy (sHDR-BT) for intraprostatic recurrence of prostate adenocarcinoma. Materials and Methods Fourteen consecutive patients treated with sHDR-BT between 2019 and 2022 were prospectively evaluated. To be considered for sHDR-BT, patients were required to have had received curative intent prostate radiotherapy previously and have biochemical failure. Patients were evaluated with bone scan and CT imaging of the chest abdomen and pelvis or PSMA-PET imaging. All patients had MRI of the prostate and trans-rectal ultrasound (US) guided biopsy proven confirmation of intraprostatic recurrence of disease. For patients who received prior BT, sHDR-BT was standardized with prescribed dose of 27Gy in 2 fractions to prostatic regions with confirmed disease on MR or biopsy. For patients had no history of prior BT, sHDR-BT was standardized with a prescribed dose of 21Gy in 2 fractions to the entire prostate with integrated boost irradiation of 27Gy in 2 fractions to the prostatic zones with confirmed disease on MR or biopsy. All plans were designed using trans-rectally acquired US image sets in Oncentra Prostate®. Post-treatment monitoring consisted of either in person or telephone (due to COVID-19) evaluation with AUA and CTCAE symptom assessments at 1, 3 and 12 months post treatment and yearly thereafter. Descriptive statistics were used to describe outcomes and the Mann-Whitney-Wilcoxon or Fisher-Freeman-Halton test used for comparisons. Results Median (inter-quartile-range) age prior to salvage treatment was 72 (67-76) years for the cohort. Seven (50%) patients had received external beam radiotherapy (EBRT) monotherapy (74-78Gy) as initial treatment for prostate cancer. One (7%) received EBRT (46Gy) + low-dose-rate BT (LDR-BT) (110Gy) and six (43%) received LDR-BT (144Gy) monotherapy as initial treatment. Four (29%) had received elective nodal irradiation (46Gy) with EBRT. Median time from initial radiotherapy to biopsy confirmation of recurrent disease was 77 (54-111) months. At baseline prior to sHDR-BT, 7 (50%) patient had significant lower urinary tract symptoms. Median AUA score was 8 (3-20) prior to sHDR-BT [Table 1]. 3 (21%) patients reported irregular bowel function and 2 (14%) reported hematochezia prior to sHDR-BT. At first fraction of sHDR-BT rectal D100cc was 8 (6-9)Gy, urethra D10% was 12 (11-15)Gy, urethra Dmax was 15 (13-16)Gy. At second fraction of sHDR-BT rectal D100cc was 8 (7-9)Gy, urethra D10% was 12 (12-14)Gy and urethra Dmax was 13 (12-16)Gy. At 1-month post treatment, median AUA score was 13 (18-21; p=0.48). On review of CTCAE scoring, at 1-mont
{"title":"PO60","authors":"Kevin Martell, Breanna Fang, Philip McGeachy, Tyler Meyer, Siraj Husain, Kundan Thind","doi":"10.1016/j.brachy.2023.06.161","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.161","url":null,"abstract":"Purpose Isolated intraprostatic recurrence of prostate adenocarcinoma post radiotherapy presents a clinically challenging situation as surgical salvage options are associated with high morbidity. Brachytherapy can be used in these cases but supportive data are limited. The present study aims to present the acute toxicity results from patients who received salvage high-dose-rate prostate brachytherapy (sHDR-BT) for intraprostatic recurrence of prostate adenocarcinoma. Materials and Methods Fourteen consecutive patients treated with sHDR-BT between 2019 and 2022 were prospectively evaluated. To be considered for sHDR-BT, patients were required to have had received curative intent prostate radiotherapy previously and have biochemical failure. Patients were evaluated with bone scan and CT imaging of the chest abdomen and pelvis or PSMA-PET imaging. All patients had MRI of the prostate and trans-rectal ultrasound (US) guided biopsy proven confirmation of intraprostatic recurrence of disease. For patients who received prior BT, sHDR-BT was standardized with prescribed dose of 27Gy in 2 fractions to prostatic regions with confirmed disease on MR or biopsy. For patients had no history of prior BT, sHDR-BT was standardized with a prescribed dose of 21Gy in 2 fractions to the entire prostate with integrated boost irradiation of 27Gy in 2 fractions to the prostatic zones with confirmed disease on MR or biopsy. All plans were designed using trans-rectally acquired US image sets in Oncentra Prostate®. Post-treatment monitoring consisted of either in person or telephone (due to COVID-19) evaluation with AUA and CTCAE symptom assessments at 1, 3 and 12 months post treatment and yearly thereafter. Descriptive statistics were used to describe outcomes and the Mann-Whitney-Wilcoxon or Fisher-Freeman-Halton test used for comparisons. Results Median (inter-quartile-range) age prior to salvage treatment was 72 (67-76) years for the cohort. Seven (50%) patients had received external beam radiotherapy (EBRT) monotherapy (74-78Gy) as initial treatment for prostate cancer. One (7%) received EBRT (46Gy) + low-dose-rate BT (LDR-BT) (110Gy) and six (43%) received LDR-BT (144Gy) monotherapy as initial treatment. Four (29%) had received elective nodal irradiation (46Gy) with EBRT. Median time from initial radiotherapy to biopsy confirmation of recurrent disease was 77 (54-111) months. At baseline prior to sHDR-BT, 7 (50%) patient had significant lower urinary tract symptoms. Median AUA score was 8 (3-20) prior to sHDR-BT [Table 1]. 3 (21%) patients reported irregular bowel function and 2 (14%) reported hematochezia prior to sHDR-BT. At first fraction of sHDR-BT rectal D100cc was 8 (6-9)Gy, urethra D10% was 12 (11-15)Gy, urethra Dmax was 15 (13-16)Gy. At second fraction of sHDR-BT rectal D100cc was 8 (7-9)Gy, urethra D10% was 12 (12-14)Gy and urethra Dmax was 13 (12-16)Gy. At 1-month post treatment, median AUA score was 13 (18-21; p=0.48). On review of CTCAE scoring, at 1-mont","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-01DOI: 10.1016/j.brachy.2023.06.202
Melisa Pasli, Sara Cowles, Jasmin Jo, Mahmoud Yaqoub, Hilal A. Kanaan, Andrew Ju, Matthew Sean Peach
Purpose Controversy exists regarding radiotherapy of patients with connective tissue disorders due to increased radiosensitivity. GammaTile® (GT Medical Technologies, Tempe, Arizona) is a novel brachytherapy strategy for intracranial radiotherapy. The suspension of the seeds in this matrix results in more uniformed dose delivery throughout the periphery of resection cavities, potentially reducing necrosis risk and conserving surrounding brain parenchyma. We hypothesized that GammaTile® would result in decreased dose to the scalp and incision wound in a patient with a Grade 3 glioma and limited scleroderma with active disease in the overlying scalp. Materials and Methods Preoperative MRI was used to estimate the number of tiles needed to deliver 60 Gy to a 5mm depth from the resection cavity. The tiles were placed after a right frontotemporal craniotomy with maximal safe resection. Day 1 post-implant dosimetry was performed with MRI and CT utilizing MIM to contour the sources and planning target volume (PTV); a 5mm expansion from the surgical cavity along tumor involved surfaces. A hypothetical standard external beam (EBRT) plan was generated in Eclipse with a 1cm expansion from the cavity and a 5mm expansion to PTV. A similar volume to GammaTile was generated using the CybrerKnife planning system with a 5 mm expansion of the cavity to PTV. Both plans were dosed to 59.3 Gy in 33 fractions to 95% coverage. All dose clouds were imported into Velocity and converted to equivalent dose in 2Gy (EQD2). Organs at risk (OARs) including the scalp and incision scar were contoured and dose volume histograms (DHVs) generated in Velocity. The patient underwent physical exam at 1, 3, and 6 months and MRI brain at 3 and 6 months, with photo documentation of the scalp. Results A total of 10 tiles were ordered and ultimately used with no tiles split to cover a 39.76 cc resection cavity as indicated on Day 1 post implant imaging. The resulting PTV was 31.18 cc with the V100% (60 Gy) of 99% and D90 of 118.7%. Compared to the GammaTile dose cloud, those generated by both EBRT plans resulted in greater irradiation to the surgical scar (Figure 1A-C, green line). Figure 1D-F shows the DVH between GammaTile (green), standard EBRT (red) and CybrerKnife (blue) for the scar, scalp and normal brain parenchyma. Overall, there was significant reduction in dose to these OARs with GammaTile. In particular, the maximum dose delivered to the scar and scalp by GammaTile was reduced to half of that from other external beam techniques (∼25-30 Gy vs ∼55 Gy). MRI imaging at 3 and 6 months lacked evidence of disease recurrence or radionecrosis. At the 6 month follow up visit, the surgical scar was well healed and there were no skin changes to the surrounding scalp at any time during follow up. Conclusions Compared to EBRT techniques, GammaTile brachytherapy is able to deliver considerably less dose to the scalp and scar incision in a Grade 3 glioma patient with limited scleroderma and ac
目的结缔组织疾病患者放射治疗因放射敏感性增高而存在争议。GammaTile®(GT Medical Technologies, Tempe, Arizona)是一种新颖的颅内放疗近距离治疗策略。悬浮在基质中的种子使得整个切除腔周围的剂量传递更加均匀，潜在地降低了坏死风险并保存了周围的脑实质。我们假设GammaTile®会导致3级胶质瘤和局限性硬皮病患者头皮和切口伤口的剂量减少，并在头皮上发生活动性疾病。材料和方法术前MRI用于估计从切除腔向5mm深度输送60 Gy所需的瓦片数量。这些瓷片是在右侧额颞叶开颅后放置的，并进行了最大限度的安全切除。植入后第1天通过MRI和CT进行剂量测定，利用MIM来轮廓源和规划靶体积(PTV);从手术腔沿肿瘤受累表面扩张5mm。在Eclipse中生成一个假设的标准外束(EBRT)计划，从腔扩展1cm，扩展到PTV 5mm。使用CybrerKnife规划系统生成与GammaTile相似的体积，将空腔扩展5 mm至PTV。两种方案的剂量均为59.3 Gy，分为33个部分，覆盖率为95%。将所有剂量云导入Velocity并转换为2Gy当量剂量(EQD2)。在Velocity中绘制包括头皮和切口疤痕在内的危险器官(OARs)并生成剂量体积直方图(dhv)。患者在1、3、6个月时进行体格检查，在3、6个月时进行脑部MRI检查，并记录头皮照片。结果共订购了10块瓦片，最终使用瓦片覆盖39.76 cc的切除腔，如种植后第1天成像所示。PTV为31.18 cc, V100% (60 Gy)为99%，D90为118.7%。与GammaTile剂量云相比，两种EBRT方案产生的剂量云对手术疤痕的照射更大(图1A-C，绿线)。图1D-F显示了疤痕、头皮和正常脑实质的GammaTile(绿色)、标准EBRT(红色)和CybrerKnife(蓝色)之间的DVH。总体而言，使用GammaTile可显著降低这些桨叶的剂量。特别是，通过GammaTile传递到疤痕和头皮的最大剂量减少到其他外部光束技术的一半(~ 25-30 Gy vs ~ 55 Gy)。3个月和6个月的MRI成像缺乏疾病复发或放射性坏死的证据。随访6个月，手术瘢痕愈合良好，随访期间周围头皮无任何皮肤变化。结论:与EBRT技术相比，GammaTile近距离放射治疗能够在伴有有限硬皮病和头皮活动性疾病的3级胶质瘤患者的头皮和疤痕切口上提供更少的剂量。患者没有出现任何预期的头皮EBRT会出现的急性毒性，也没有切口愈合问题。本报告展示了gamma matile照射治疗颅内肿瘤和局限性硬皮病患者的剂量学和临床益处，并应考虑用于类似结缔组织病患者。由于放射敏感性增高，结缔组织疾病患者的放射治疗存在争议。GammaTile®(GT Medical Technologies, Tempe, Arizona)是一种新颖的颅内放疗近距离治疗策略。悬浮在基质中的种子使得整个切除腔周围的剂量传递更加均匀，潜在地降低了坏死风险并保存了周围的脑实质。我们假设GammaTile®会导致3级胶质瘤和局限性硬皮病患者头皮和切口伤口的剂量减少，并在头皮上发生活动性疾病。术前MRI用于估计从切除腔向5mm深度输送60 Gy所需的瓦片数量。这些瓷片是在右侧额颞叶开颅后放置的，并进行了最大限度的安全切除。植入后第1天通过MRI和CT进行剂量测定，利用MIM来轮廓源和规划靶体积(PTV);从手术腔沿肿瘤受累表面扩张5mm。在Eclipse中生成一个假设的标准外束(EBRT)计划，从腔扩展1cm，扩展到PTV 5mm。使用CybrerKnife规划系统生成与GammaTile相似的体积，将空腔扩展5 mm至PTV。两种方案的剂量均为59.3 Gy，分为33个部分，覆盖率为95%。将所有剂量云导入Velocity并转换为2Gy当量剂量(EQD2)。
{"title":"Miscellaneous Posters PO101","authors":"Melisa Pasli, Sara Cowles, Jasmin Jo, Mahmoud Yaqoub, Hilal A. Kanaan, Andrew Ju, Matthew Sean Peach","doi":"10.1016/j.brachy.2023.06.202","DOIUrl":"https://doi.org/10.1016/j.brachy.2023.06.202","url":null,"abstract":"Purpose Controversy exists regarding radiotherapy of patients with connective tissue disorders due to increased radiosensitivity. GammaTile® (GT Medical Technologies, Tempe, Arizona) is a novel brachytherapy strategy for intracranial radiotherapy. The suspension of the seeds in this matrix results in more uniformed dose delivery throughout the periphery of resection cavities, potentially reducing necrosis risk and conserving surrounding brain parenchyma. We hypothesized that GammaTile® would result in decreased dose to the scalp and incision wound in a patient with a Grade 3 glioma and limited scleroderma with active disease in the overlying scalp. Materials and Methods Preoperative MRI was used to estimate the number of tiles needed to deliver 60 Gy to a 5mm depth from the resection cavity. The tiles were placed after a right frontotemporal craniotomy with maximal safe resection. Day 1 post-implant dosimetry was performed with MRI and CT utilizing MIM to contour the sources and planning target volume (PTV); a 5mm expansion from the surgical cavity along tumor involved surfaces. A hypothetical standard external beam (EBRT) plan was generated in Eclipse with a 1cm expansion from the cavity and a 5mm expansion to PTV. A similar volume to GammaTile was generated using the CybrerKnife planning system with a 5 mm expansion of the cavity to PTV. Both plans were dosed to 59.3 Gy in 33 fractions to 95% coverage. All dose clouds were imported into Velocity and converted to equivalent dose in 2Gy (EQD2). Organs at risk (OARs) including the scalp and incision scar were contoured and dose volume histograms (DHVs) generated in Velocity. The patient underwent physical exam at 1, 3, and 6 months and MRI brain at 3 and 6 months, with photo documentation of the scalp. Results A total of 10 tiles were ordered and ultimately used with no tiles split to cover a 39.76 cc resection cavity as indicated on Day 1 post implant imaging. The resulting PTV was 31.18 cc with the V100% (60 Gy) of 99% and D90 of 118.7%. Compared to the GammaTile dose cloud, those generated by both EBRT plans resulted in greater irradiation to the surgical scar (Figure 1A-C, green line). Figure 1D-F shows the DVH between GammaTile (green), standard EBRT (red) and CybrerKnife (blue) for the scar, scalp and normal brain parenchyma. Overall, there was significant reduction in dose to these OARs with GammaTile. In particular, the maximum dose delivered to the scar and scalp by GammaTile was reduced to half of that from other external beam techniques (∼25-30 Gy vs ∼55 Gy). MRI imaging at 3 and 6 months lacked evidence of disease recurrence or radionecrosis. At the 6 month follow up visit, the surgical scar was well healed and there were no skin changes to the surrounding scalp at any time during follow up. Conclusions Compared to EBRT techniques, GammaTile brachytherapy is able to deliver considerably less dose to the scalp and scar incision in a Grade 3 glioma patient with limited scleroderma and ac","PeriodicalId":93914,"journal":{"name":"Brachytherapy","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135434599","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：