Conclusion DD allows the acquisition of CT images at different kV settings with only one calibrat... more Conclusion DD allows the acquisition of CT images at different kV settings with only one calibration curve in the planning system, with a minimum impact in dose calculations. However it needs matching with the original FBP images for volume delineation due to the lower image quality. Consequently Direct Density™ is accurate enough to be introduced in clinical routine. EP-2040 IDose4 algorithm for radiotherapy planning process: how reduce the dose without image quality loss
Purpose/Objective: The purpose of this study is to evaluate our first experience with 3D image-gu... more Purpose/Objective: The purpose of this study is to evaluate our first experience with 3D image-guided breast brachytherapy (BT) and to compare dose distribution parameters between Paris dosimetry treatment plans and image-based treatment plans. Materials and Methods: First, 49 consecutive breast cancer patients treated with high dose rate (HDR) interstitial brachytherapy were selected for the study. All patients received 10Gy boost dose after whole breast irradiation. Every patient underwent computed tomography and the planning target volume (PTV) and organs at risk (OAR) were outlined. Two treatment plans were created for every patient. First, based on a Paris dosimetry system (PDS), and the second one, imaged-based plan with graphical optimization (OPT). The reference isodose in PDS implants was 85%, whereas in OPT plans the isodose was chosen to obtain proper target coverage. Dose and volume parameters (D90, D100, V90, V100), dose at OARs, total reference air kerma (TRAK) and quality assurance parameters: dose nonuniformity ratio (DNR), dose homogeneity index (DHI), external volume index (EI) and conformal index (COIN) were used for a comparison of both plans. Results: One-, two-, three-plane implants were used. The mean number of catheters was 7, but the mean for first 20 patients was 5 and almost 9 catheters for the next 29 patients. The volume of PTV ranged from 13,6 cm 3 to 163,4 cm 3 (mean: 58,2 cm 3). The mean value of isodose selected for prescribing the dose for OPT plans was 73%. The mean D90 was 88,2% and 105,8%, the D100 was 59,8% and 75,7%, the V90 was 88,6% and 98,1%, the V100 was 79,9% and 98,9% and the TRAK was 0,00375 Gym-1 and 0,00439 Gym-1 for the PDS and OPT plans respectively. The mean DNR was 0,29 and 0,42, the DHI was 0,71 and 0,58, the EI was 0,15 and 0,23 and the COIN was 0,68 and 0,76 respectively. All differences are statistically significant. Conclusions: The target coverage in image-guided plans (OPT) was significantly higher than in plans based on Paris dosimetry system (PDS), but the dose homogeneity was worse. Also value of TRAK increased because of change of prescribing isodose. Our first experience proved, that more number of needles allows to obtain better dose distribution.
Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified u... more Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified using new imaging techniques with the potential to focally boost this region for improved local control without undue additional toxicity compared to conventional techniques and dose escalation. Data from a large HDR study has shown that hypofractionated doses with a BED of >268 Gy (α/β 1.2 Gy) have a significantly higher biochemical relapse-free survival (bRFS) than lower BED doses. Only one published trial to date has given doses such as these using external beam therapy, with acceptable early toxicity. Objective: To establish if a simultaneous integrated prostate boost (PB) of 268 Gy BED can be delivered without violating known Cyberknife OAR constraints Materials and Methods: 14 patient plans were constructed using various simulated boost volumes and locations. The whole prostate received 36.25Gy in 5 fractions with 47.5Gy in 5 fractions (BED 273 Gy, α/β=2 Gy) to the simulated PB volume. The objective was to deliver the above doses whilst respecting the dose constraints (Table 1) which were constructed from our clinical constraints plus reasonable minor and major relaxations, extrapolated from practice in clinical trials. Target constraints were applied to penile bulb (D50% <18.1 Gy), right and left femoral heads (5%<14.5 Gy) and bowel (<5cc to 19.5 Gy). Testicles were used as a blocking structure. The urethra was not visible but a simulated urethra position was drawn to estimate dose.
Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified u... more Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified using new imaging techniques with the potential to focally boost this region for improved local control without undue additional toxicity compared to conventional techniques and dose escalation. Data from a large HDR study has shown that hypofractionated doses with a BED of >268 Gy (α/β 1.2 Gy) have a significantly higher biochemical relapse-free survival (bRFS) than lower BED doses. Only one published trial to date has given doses such as these using external beam therapy, with acceptable early toxicity. Objective: To establish if a simultaneous integrated prostate boost (PB) of 268 Gy BED can be delivered without violating known Cyberknife OAR constraints Materials and Methods: 14 patient plans were constructed using various simulated boost volumes and locations. The whole prostate received 36.25Gy in 5 fractions with 47.5Gy in 5 fractions (BED 273 Gy, α/β=2 Gy) to the simulated PB volume. The objective was to deliver the above doses whilst respecting the dose constraints (Table 1) which were constructed from our clinical constraints plus reasonable minor and major relaxations, extrapolated from practice in clinical trials. Target constraints were applied to penile bulb (D50% <18.1 Gy), right and left femoral heads (5%<14.5 Gy) and bowel (<5cc to 19.5 Gy). Testicles were used as a blocking structure. The urethra was not visible but a simulated urethra position was drawn to estimate dose.
PURPOSE This paper describes the protocol for the development of 3D-printed custom applicators in... more PURPOSE This paper describes the protocol for the development of 3D-printed custom applicators in treating skin carcinoma, the evaluation of the materials used, and the methods for segmentation and rendering of the applicators. MATERIAL AND METHODS The segmentation and rendering process for the applicator had six phases: (i) determination of the volume of the lesion using a computed tomography (CT) scan; (ii) delineation of the patient surface, using the same CT images; (iii) creation of the applicator in the planner and segmentation of the mold; (iv) preliminary dosimetry and establishment of the route of the catheter from the brachytherapy unit; (v) creation of the 3D applicator using specialized software; and (vi) applicator printing. Following this process, the patient returned for a second CT to undergo the definitive dosimetry with the applicator in place. Radiation therapy was then administered. RESULTS We made a total of 16 applicators. Only three applicators had to be remade, two due to an error in the infill and the other due to incorrect catheter geometry. In all cases, correct coverage of the planning target volume was achieved with the prescribed isodose. CONCLUSIONS The creation of custom molds in plesiotherapy for skin cancer with 3D printing is feasible. Compared to manual methods, 3D printing increases precision in applicator geometry and optimization of the dosimetry.
... Siga los consejos alimenticios de la sección de cabeza y cuello. No fume ni beba.Mama No util... more ... Siga los consejos alimenticios de la sección de cabeza y cuello. No fume ni beba.Mama No utilice sujetador habitual hasta las tres semanas del final del tratamiento, vístase con una camiseta de algodón de manga corta. No ...
Reports of Practical Oncology & Radiotherapy, 2013
Hi, I'm Elsa.. . I'm a Cancer survivor.. . 12 years ago I was having problems with a spot of the ... more Hi, I'm Elsa.. . I'm a Cancer survivor.. . 12 years ago I was having problems with a spot of the skin. I didn't think too much about it because I thought I had, as my workmate called them mole. After about 6 months I decided to have my doctor check me. I told her I thought I had a mole and she sent me to do a skin biopsy to and a blood test. I was so relieved to find the blood test was negative but the skin biopsy had not been resolved. So again I thought a mole-I figured I could live with that, after all my workmate did! The doctor told me he would get back to me in a couple of days. He did and told me he had made arrangements with the hospital-I had to be operated on-IMMEDIATELY. I had a skin cancer named MELANOMA. A good deal of my skin was removed. The writing of that booklet encouraged me to start the support group I searched for so fervently. The Melanoma Alliance from Vigo-became a reality! If you or someone you know is in a similar situation, have them email the alliance at
International Journal of Radiation Oncology*Biology*Physics, 2004
SBRT group, 2/9 deaths were from NSCLC. Postoperative complications occurred in 26% of the SLR gr... more SBRT group, 2/9 deaths were from NSCLC. Postoperative complications occurred in 26% of the SLR group, including 1 cardiac, 1 sepsis, 1 pneumonia, and 2 air leaks. Median postoperative hospital stay was 8 days (3-49). There were no grade III toxicities in the SBRT group. Conclusions: Our exploratory analysis of matched pts suggests that local control and failure rates are similar for SBRT and SLR. SBRT has low risk of toxicity and may avoid postoperative complications and extended hospital stays with similar outcome. Similar disease control and cancer-related survival, despite more co-morbid deaths in the SBRT cohort, suggests these treatments warrant further comparison. A prospective randomized study comparing SBRT and SLR is reasonable for pts who are not candidates for lobectomy, but whose pulmonary status would allow for SLR.
Reports of Practical Oncology & Radiotherapy, 2013
Material and methods. The new image guided AlignRT system is based on structured light. A protoco... more Material and methods. The new image guided AlignRT system is based on structured light. A protocol has been developed to establish tolerances for accepting patient positioning and to control possible changes in the treatment volume, taking into account the information given by the AlignRT. We performed a prospective study in a group of patients diagnosed with breast cancer with indication for breast irradiation after conservative surgery. We collected and corrected in real time the deviations recorded in the conventional positioning of the patient. Patients who have undergone significant changes in the volume of treatment have been replanned. Result. By analyzing the recorded correction values, which ensures correct daily positioning of the patient, we observe variations above one centimeter at some parameters. To adequately cover the ranges associated with treatment volume, we determined that the percentage of matching treatment-planning surfaces within a tolerance of 3 mm should be above 70%. The use of the system has allowed recording changes in the volume and the determination of treatment replanning in 10-30% of patients, depending on the time elapsed between the planning CT and the start of treatment. Furthermore we achieved to decrease the time necessary to guarantee correct daily positioning. Conclusions. This system ensures proper IGRT daily reproduction treatment, reduces the time necessary to allow patient positioning and show treatment volume disturbances. Furthermore, it is an innocuous system for the patient.
Purpose Our center adopted high-dose-rate brachytherapy with surface applicators (plesiotherapy) ... more Purpose Our center adopted high-dose-rate brachytherapy with surface applicators (plesiotherapy) in 2008, creating custom molds to treat irregular areas. This study describes the efficacy and safety outcomes after extensive follow-up in the patients. Methods/patients We planned the treatment using two computed tomography (CT) scans: the first to delineate the lesion and the second after placing the thermoplastic mold. Fusing the two CT images enables planning of the target volume and pinpointing, where the catheters are in the mold. Results Seventy patients received plesiotherapy, either exclusively or following excision in patients with risk factors for recurrence. Those receiving plesiotherapy alone showed a complete response rate of 95.8%, and recurrences occurred in 5.7% at a mean follow-up of 96.2 months. Chronic toxicity appeared in 26.6% of patients, but severity was limited to grade 1 or 2. Conclusions High-dose-rate brachytherapy with customized molds yields a high rate of ...
BackgroundConservative surgery followed by breast and nodal irradiation is the standard loco-regi... more BackgroundConservative surgery followed by breast and nodal irradiation is the standard loco-regional early breast cancer (BC) treatment for patients with four or more involved lymph nodes. However, the treatment strategy when fewer nodes are involved remains unclear, especially when lymphadenectomy has not been performed. Sensitive nodal status assessment molecular techniques as the One-Step Nucleic Acid Amplification (OSNA) assay can contribute to the definition and standardization of the treatment strategy. Therefore, the OPTIMAL study aims to demonstrate the feasibility of incidental irradiation of axillary nodes in patients with early-stage BC and limited involvement of the SLN.MethodsBC patients who underwent conservative surgery and whose SLN total tumour load assessed with OSNA ranged between 250–15,000 copies/µL will be eligible. Patients will be randomized to receive irradiation on the breast, tumour bed, axillary and supraclavicular lymph node areas (intentional arm) or o...
Conclusion DD allows the acquisition of CT images at different kV settings with only one calibrat... more Conclusion DD allows the acquisition of CT images at different kV settings with only one calibration curve in the planning system, with a minimum impact in dose calculations. However it needs matching with the original FBP images for volume delineation due to the lower image quality. Consequently Direct Density™ is accurate enough to be introduced in clinical routine. EP-2040 IDose4 algorithm for radiotherapy planning process: how reduce the dose without image quality loss
Purpose/Objective: The purpose of this study is to evaluate our first experience with 3D image-gu... more Purpose/Objective: The purpose of this study is to evaluate our first experience with 3D image-guided breast brachytherapy (BT) and to compare dose distribution parameters between Paris dosimetry treatment plans and image-based treatment plans. Materials and Methods: First, 49 consecutive breast cancer patients treated with high dose rate (HDR) interstitial brachytherapy were selected for the study. All patients received 10Gy boost dose after whole breast irradiation. Every patient underwent computed tomography and the planning target volume (PTV) and organs at risk (OAR) were outlined. Two treatment plans were created for every patient. First, based on a Paris dosimetry system (PDS), and the second one, imaged-based plan with graphical optimization (OPT). The reference isodose in PDS implants was 85%, whereas in OPT plans the isodose was chosen to obtain proper target coverage. Dose and volume parameters (D90, D100, V90, V100), dose at OARs, total reference air kerma (TRAK) and quality assurance parameters: dose nonuniformity ratio (DNR), dose homogeneity index (DHI), external volume index (EI) and conformal index (COIN) were used for a comparison of both plans. Results: One-, two-, three-plane implants were used. The mean number of catheters was 7, but the mean for first 20 patients was 5 and almost 9 catheters for the next 29 patients. The volume of PTV ranged from 13,6 cm 3 to 163,4 cm 3 (mean: 58,2 cm 3). The mean value of isodose selected for prescribing the dose for OPT plans was 73%. The mean D90 was 88,2% and 105,8%, the D100 was 59,8% and 75,7%, the V90 was 88,6% and 98,1%, the V100 was 79,9% and 98,9% and the TRAK was 0,00375 Gym-1 and 0,00439 Gym-1 for the PDS and OPT plans respectively. The mean DNR was 0,29 and 0,42, the DHI was 0,71 and 0,58, the EI was 0,15 and 0,23 and the COIN was 0,68 and 0,76 respectively. All differences are statistically significant. Conclusions: The target coverage in image-guided plans (OPT) was significantly higher than in plans based on Paris dosimetry system (PDS), but the dose homogeneity was worse. Also value of TRAK increased because of change of prescribing isodose. Our first experience proved, that more number of needles allows to obtain better dose distribution.
Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified u... more Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified using new imaging techniques with the potential to focally boost this region for improved local control without undue additional toxicity compared to conventional techniques and dose escalation. Data from a large HDR study has shown that hypofractionated doses with a BED of >268 Gy (α/β 1.2 Gy) have a significantly higher biochemical relapse-free survival (bRFS) than lower BED doses. Only one published trial to date has given doses such as these using external beam therapy, with acceptable early toxicity. Objective: To establish if a simultaneous integrated prostate boost (PB) of 268 Gy BED can be delivered without violating known Cyberknife OAR constraints Materials and Methods: 14 patient plans were constructed using various simulated boost volumes and locations. The whole prostate received 36.25Gy in 5 fractions with 47.5Gy in 5 fractions (BED 273 Gy, α/β=2 Gy) to the simulated PB volume. The objective was to deliver the above doses whilst respecting the dose constraints (Table 1) which were constructed from our clinical constraints plus reasonable minor and major relaxations, extrapolated from practice in clinical trials. Target constraints were applied to penile bulb (D50% <18.1 Gy), right and left femoral heads (5%<14.5 Gy) and bowel (<5cc to 19.5 Gy). Testicles were used as a blocking structure. The urethra was not visible but a simulated urethra position was drawn to estimate dose.
Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified u... more Purpose/Objective: Background: The dominant intra-prostatic tumour region can now be identified using new imaging techniques with the potential to focally boost this region for improved local control without undue additional toxicity compared to conventional techniques and dose escalation. Data from a large HDR study has shown that hypofractionated doses with a BED of >268 Gy (α/β 1.2 Gy) have a significantly higher biochemical relapse-free survival (bRFS) than lower BED doses. Only one published trial to date has given doses such as these using external beam therapy, with acceptable early toxicity. Objective: To establish if a simultaneous integrated prostate boost (PB) of 268 Gy BED can be delivered without violating known Cyberknife OAR constraints Materials and Methods: 14 patient plans were constructed using various simulated boost volumes and locations. The whole prostate received 36.25Gy in 5 fractions with 47.5Gy in 5 fractions (BED 273 Gy, α/β=2 Gy) to the simulated PB volume. The objective was to deliver the above doses whilst respecting the dose constraints (Table 1) which were constructed from our clinical constraints plus reasonable minor and major relaxations, extrapolated from practice in clinical trials. Target constraints were applied to penile bulb (D50% <18.1 Gy), right and left femoral heads (5%<14.5 Gy) and bowel (<5cc to 19.5 Gy). Testicles were used as a blocking structure. The urethra was not visible but a simulated urethra position was drawn to estimate dose.
PURPOSE This paper describes the protocol for the development of 3D-printed custom applicators in... more PURPOSE This paper describes the protocol for the development of 3D-printed custom applicators in treating skin carcinoma, the evaluation of the materials used, and the methods for segmentation and rendering of the applicators. MATERIAL AND METHODS The segmentation and rendering process for the applicator had six phases: (i) determination of the volume of the lesion using a computed tomography (CT) scan; (ii) delineation of the patient surface, using the same CT images; (iii) creation of the applicator in the planner and segmentation of the mold; (iv) preliminary dosimetry and establishment of the route of the catheter from the brachytherapy unit; (v) creation of the 3D applicator using specialized software; and (vi) applicator printing. Following this process, the patient returned for a second CT to undergo the definitive dosimetry with the applicator in place. Radiation therapy was then administered. RESULTS We made a total of 16 applicators. Only three applicators had to be remade, two due to an error in the infill and the other due to incorrect catheter geometry. In all cases, correct coverage of the planning target volume was achieved with the prescribed isodose. CONCLUSIONS The creation of custom molds in plesiotherapy for skin cancer with 3D printing is feasible. Compared to manual methods, 3D printing increases precision in applicator geometry and optimization of the dosimetry.
... Siga los consejos alimenticios de la sección de cabeza y cuello. No fume ni beba.Mama No util... more ... Siga los consejos alimenticios de la sección de cabeza y cuello. No fume ni beba.Mama No utilice sujetador habitual hasta las tres semanas del final del tratamiento, vístase con una camiseta de algodón de manga corta. No ...
Reports of Practical Oncology & Radiotherapy, 2013
Hi, I'm Elsa.. . I'm a Cancer survivor.. . 12 years ago I was having problems with a spot of the ... more Hi, I'm Elsa.. . I'm a Cancer survivor.. . 12 years ago I was having problems with a spot of the skin. I didn't think too much about it because I thought I had, as my workmate called them mole. After about 6 months I decided to have my doctor check me. I told her I thought I had a mole and she sent me to do a skin biopsy to and a blood test. I was so relieved to find the blood test was negative but the skin biopsy had not been resolved. So again I thought a mole-I figured I could live with that, after all my workmate did! The doctor told me he would get back to me in a couple of days. He did and told me he had made arrangements with the hospital-I had to be operated on-IMMEDIATELY. I had a skin cancer named MELANOMA. A good deal of my skin was removed. The writing of that booklet encouraged me to start the support group I searched for so fervently. The Melanoma Alliance from Vigo-became a reality! If you or someone you know is in a similar situation, have them email the alliance at
International Journal of Radiation Oncology*Biology*Physics, 2004
SBRT group, 2/9 deaths were from NSCLC. Postoperative complications occurred in 26% of the SLR gr... more SBRT group, 2/9 deaths were from NSCLC. Postoperative complications occurred in 26% of the SLR group, including 1 cardiac, 1 sepsis, 1 pneumonia, and 2 air leaks. Median postoperative hospital stay was 8 days (3-49). There were no grade III toxicities in the SBRT group. Conclusions: Our exploratory analysis of matched pts suggests that local control and failure rates are similar for SBRT and SLR. SBRT has low risk of toxicity and may avoid postoperative complications and extended hospital stays with similar outcome. Similar disease control and cancer-related survival, despite more co-morbid deaths in the SBRT cohort, suggests these treatments warrant further comparison. A prospective randomized study comparing SBRT and SLR is reasonable for pts who are not candidates for lobectomy, but whose pulmonary status would allow for SLR.
Reports of Practical Oncology & Radiotherapy, 2013
Material and methods. The new image guided AlignRT system is based on structured light. A protoco... more Material and methods. The new image guided AlignRT system is based on structured light. A protocol has been developed to establish tolerances for accepting patient positioning and to control possible changes in the treatment volume, taking into account the information given by the AlignRT. We performed a prospective study in a group of patients diagnosed with breast cancer with indication for breast irradiation after conservative surgery. We collected and corrected in real time the deviations recorded in the conventional positioning of the patient. Patients who have undergone significant changes in the volume of treatment have been replanned. Result. By analyzing the recorded correction values, which ensures correct daily positioning of the patient, we observe variations above one centimeter at some parameters. To adequately cover the ranges associated with treatment volume, we determined that the percentage of matching treatment-planning surfaces within a tolerance of 3 mm should be above 70%. The use of the system has allowed recording changes in the volume and the determination of treatment replanning in 10-30% of patients, depending on the time elapsed between the planning CT and the start of treatment. Furthermore we achieved to decrease the time necessary to guarantee correct daily positioning. Conclusions. This system ensures proper IGRT daily reproduction treatment, reduces the time necessary to allow patient positioning and show treatment volume disturbances. Furthermore, it is an innocuous system for the patient.
Purpose Our center adopted high-dose-rate brachytherapy with surface applicators (plesiotherapy) ... more Purpose Our center adopted high-dose-rate brachytherapy with surface applicators (plesiotherapy) in 2008, creating custom molds to treat irregular areas. This study describes the efficacy and safety outcomes after extensive follow-up in the patients. Methods/patients We planned the treatment using two computed tomography (CT) scans: the first to delineate the lesion and the second after placing the thermoplastic mold. Fusing the two CT images enables planning of the target volume and pinpointing, where the catheters are in the mold. Results Seventy patients received plesiotherapy, either exclusively or following excision in patients with risk factors for recurrence. Those receiving plesiotherapy alone showed a complete response rate of 95.8%, and recurrences occurred in 5.7% at a mean follow-up of 96.2 months. Chronic toxicity appeared in 26.6% of patients, but severity was limited to grade 1 or 2. Conclusions High-dose-rate brachytherapy with customized molds yields a high rate of ...
BackgroundConservative surgery followed by breast and nodal irradiation is the standard loco-regi... more BackgroundConservative surgery followed by breast and nodal irradiation is the standard loco-regional early breast cancer (BC) treatment for patients with four or more involved lymph nodes. However, the treatment strategy when fewer nodes are involved remains unclear, especially when lymphadenectomy has not been performed. Sensitive nodal status assessment molecular techniques as the One-Step Nucleic Acid Amplification (OSNA) assay can contribute to the definition and standardization of the treatment strategy. Therefore, the OPTIMAL study aims to demonstrate the feasibility of incidental irradiation of axillary nodes in patients with early-stage BC and limited involvement of the SLN.MethodsBC patients who underwent conservative surgery and whose SLN total tumour load assessed with OSNA ranged between 250–15,000 copies/µL will be eligible. Patients will be randomized to receive irradiation on the breast, tumour bed, axillary and supraclavicular lymph node areas (intentional arm) or o...
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