The evaluation of radiation burden in vivo is crucial in modern radiology as stated also in the E... more The evaluation of radiation burden in vivo is crucial in modern radiology as stated also in the European Directive 2013/59/Euratom—Basic Safety Standard. Although radiation dose monitoring can impact the justification and optimization of radiological procedure, as well as effective patient communication, standardization of radiation monitoring software is far to be achieved. Toward this goal, the Italian Association of Medical Physics (AIFM) published a report describing the state of the art and standard guidelines in radiation dose monitoring system quality assurance. This article reports the AIFM statement about radiation dose monitoring systems (RDMSs) summarizing the different critical points of the systems related to Medical Physicist Expert (MPE) activities before, during, and after their clinical implementation. In particular, the article describes the general aspects of radiation dose data management, radiation dose monitoring systems, data integrity, and data responsibiliti...
Poster: "ECR 2015 / C-2102 / The use of iterative reconstruction algorithm for dose reductio... more Poster: "ECR 2015 / C-2102 / The use of iterative reconstruction algorithm for dose reduction in follow-up thorax-abdomen CT exams" by: "M. Poli, C. Bracco, S. Mazzetti, D. Campanella, D. Regge, M. Stasi; Candiolo/IT"
PURPOSE To report how the adoption of a Lean Thinking mindset in the management of a national wor... more PURPOSE To report how the adoption of a Lean Thinking mindset in the management of a national working group (WG) on the physics of Stereotactic Body Radiation Therapy (SBRT) contributed to achieve SBRT standardization objectives. METHODS Vision for the WG has been established as fragmentation reduction and process harmonization enhancement in SBRT for Italian centers. Two main research themes of the technical aspects of SBRT emerged as areas with major standardization improvement needs: small fields dosimetry and SBRT planning comparisons, to be investigated through multi-institutional studies. The management of the WG leveraged on the Lean concept of fostering self-organization in a non-hierarchical environment. Four progressive involvement levels were defined for each study. No specific "scientific" pre-experience was required to propose and coordinate a project, just requiring a voluntary commitment. People engagement was measured in terms of number of published articles. The standardization goals have been conducted through a simplified "5S" (Sort, Set in Order, Shine, Standardize, and Sustain) methodology, first considering a phase of awareness (the first three "S"), then identifying and implementing standardization actions (the last two "S"). RESULTS Since the beginning, 157 medical physicists joined the AIFM/SBRT-WG. Twenty-four papers/reviews/letters have been published in the period 2014-2019 on major Radiation Oncology journals, authored by >100 physicists (>50% working in small hospitals). Six over 12 first authors worked in peripheral/small hospitals, with no prior publication as first author. These studies contributed to the awareness and standardization phases for both small field dosimetry and planning. In particular, errors in small field measurements in 8% of centers were detected thanks to a generalized output factor curve in function of the effective field size created by averaging data available from different Linacs. Furthermore, planner's experience in SBRT was correlated with dosimetric parameters in the awareness phase; while sharing median dose volume histograms (DVHs) reduced variability among centers whilst keeping the same level of plan complexity. Finally, all the dosimetric parameters statistically significant to the planner experience during the awareness phase, were no longer significantly different in the standardization phase. CONCLUSIONS The experience of our SBRT-WG has shown how a Lean Thinking mindset could foster the SBRT procedure standardization and spread the physics of SBRT knowledge, enhancing personal growth. Our expectation is to inspire other scientific societies that have to deal with fragmented contexts or pursue processes harmonization through Lean principles.
Introduction In modern radiation therapy accurate dosimetry within small photon fields is a chall... more Introduction In modern radiation therapy accurate dosimetry within small photon fields is a challenge. The aim of the study is to investigate the main dosimetric characteristics of a new small field detector. Material and methods An Exradin A26 microionization chamber was tested. Short term stability, dose linearity, polarity effect, angular dependence and energy dependence were evaluated for field sizes up to 10 × 10 cm 2 . Results were compared with those obtained with an Exradin A1SL IC. PDD curves, OAR profiles and OF values were measured for different field sizes. The results were compared with those obtained with an IC and an EDGE diode. Results A26 IC readings showed a 0.2% and 0.1% relative standard deviation for 3 × 3 and 10 × 10 cm 2 fields, respectively. Dose response was linear to within 0.5%. The microchamber showed the maximum variation from the reference condition at the lowest dose rate. The polarity effect is within 0.5% for field size greater than 2 × 2 cm 2 ; for field size less than 2 × 2 cm 2 the effect increases, still remaining within 1%. No energy and angular dependence were observed. A26 IC PDD measurements agreed with those obtained with the EDGE diode. FWHM values show a better agreement with the EDGE diode values than A1SL. The penumbra values were greater than those obtained with the EDGE diode. Of values showed a good agreement with EDGE diode ones. Conclusions The study confirms A26 IC as a reference detector for PDD and OAR measurements.
The aim of this paper is to report definitive outcome of prostate cancer patients treated with do... more The aim of this paper is to report definitive outcome of prostate cancer patients treated with dose escalation during a period of 12.5 years. From October 1999 to March 2012 we treated 1080 patients affected by prostate cancer, using External Beam Radiotherapy (EBRT). The mean age was 69.2 years. Most of patients (69%) were staged as cT2, Gleason Score (GS) < 7; the mean iPSA 18 ng/ml; the rate of clinical positive nodes was 1%. Our intention to treat was the following: for low risk patients 72 Gy; for intermediate risk patients 75.6 Gy and for high-very high risk patients 79.2 Gy in 1.8 Gy/day fractions. From 2008 we changed the fractionation scheme and the doses were the following: for low risk patients 74 Gy and for intermediate and high-very high risk patients 78 Gy in 2.0 Gy/day fractions. Whole pelvis irradiation was performed in high-very high risk patients with 43.2-50.4 Gy in 1.8 Gy per day. The mean follow-up was 81 months. For the whole population at 5 and 10 years, th...
The evaluation of radiation burden in vivo is crucial in modern radiology as stated also in the E... more The evaluation of radiation burden in vivo is crucial in modern radiology as stated also in the European Directive 2013/59/Euratom—Basic Safety Standard. Although radiation dose monitoring can impact the justification and optimization of radiological procedure, as well as effective patient communication, standardization of radiation monitoring software is far to be achieved. Toward this goal, the Italian Association of Medical Physics (AIFM) published a report describing the state of the art and standard guidelines in radiation dose monitoring system quality assurance. This article reports the AIFM statement about radiation dose monitoring systems (RDMSs) summarizing the different critical points of the systems related to Medical Physicist Expert (MPE) activities before, during, and after their clinical implementation. In particular, the article describes the general aspects of radiation dose data management, radiation dose monitoring systems, data integrity, and data responsibiliti...
Poster: "ECR 2015 / C-2102 / The use of iterative reconstruction algorithm for dose reductio... more Poster: "ECR 2015 / C-2102 / The use of iterative reconstruction algorithm for dose reduction in follow-up thorax-abdomen CT exams" by: "M. Poli, C. Bracco, S. Mazzetti, D. Campanella, D. Regge, M. Stasi; Candiolo/IT"
PURPOSE To report how the adoption of a Lean Thinking mindset in the management of a national wor... more PURPOSE To report how the adoption of a Lean Thinking mindset in the management of a national working group (WG) on the physics of Stereotactic Body Radiation Therapy (SBRT) contributed to achieve SBRT standardization objectives. METHODS Vision for the WG has been established as fragmentation reduction and process harmonization enhancement in SBRT for Italian centers. Two main research themes of the technical aspects of SBRT emerged as areas with major standardization improvement needs: small fields dosimetry and SBRT planning comparisons, to be investigated through multi-institutional studies. The management of the WG leveraged on the Lean concept of fostering self-organization in a non-hierarchical environment. Four progressive involvement levels were defined for each study. No specific "scientific" pre-experience was required to propose and coordinate a project, just requiring a voluntary commitment. People engagement was measured in terms of number of published articles. The standardization goals have been conducted through a simplified "5S" (Sort, Set in Order, Shine, Standardize, and Sustain) methodology, first considering a phase of awareness (the first three "S"), then identifying and implementing standardization actions (the last two "S"). RESULTS Since the beginning, 157 medical physicists joined the AIFM/SBRT-WG. Twenty-four papers/reviews/letters have been published in the period 2014-2019 on major Radiation Oncology journals, authored by >100 physicists (>50% working in small hospitals). Six over 12 first authors worked in peripheral/small hospitals, with no prior publication as first author. These studies contributed to the awareness and standardization phases for both small field dosimetry and planning. In particular, errors in small field measurements in 8% of centers were detected thanks to a generalized output factor curve in function of the effective field size created by averaging data available from different Linacs. Furthermore, planner's experience in SBRT was correlated with dosimetric parameters in the awareness phase; while sharing median dose volume histograms (DVHs) reduced variability among centers whilst keeping the same level of plan complexity. Finally, all the dosimetric parameters statistically significant to the planner experience during the awareness phase, were no longer significantly different in the standardization phase. CONCLUSIONS The experience of our SBRT-WG has shown how a Lean Thinking mindset could foster the SBRT procedure standardization and spread the physics of SBRT knowledge, enhancing personal growth. Our expectation is to inspire other scientific societies that have to deal with fragmented contexts or pursue processes harmonization through Lean principles.
Introduction In modern radiation therapy accurate dosimetry within small photon fields is a chall... more Introduction In modern radiation therapy accurate dosimetry within small photon fields is a challenge. The aim of the study is to investigate the main dosimetric characteristics of a new small field detector. Material and methods An Exradin A26 microionization chamber was tested. Short term stability, dose linearity, polarity effect, angular dependence and energy dependence were evaluated for field sizes up to 10 × 10 cm 2 . Results were compared with those obtained with an Exradin A1SL IC. PDD curves, OAR profiles and OF values were measured for different field sizes. The results were compared with those obtained with an IC and an EDGE diode. Results A26 IC readings showed a 0.2% and 0.1% relative standard deviation for 3 × 3 and 10 × 10 cm 2 fields, respectively. Dose response was linear to within 0.5%. The microchamber showed the maximum variation from the reference condition at the lowest dose rate. The polarity effect is within 0.5% for field size greater than 2 × 2 cm 2 ; for field size less than 2 × 2 cm 2 the effect increases, still remaining within 1%. No energy and angular dependence were observed. A26 IC PDD measurements agreed with those obtained with the EDGE diode. FWHM values show a better agreement with the EDGE diode values than A1SL. The penumbra values were greater than those obtained with the EDGE diode. Of values showed a good agreement with EDGE diode ones. Conclusions The study confirms A26 IC as a reference detector for PDD and OAR measurements.
The aim of this paper is to report definitive outcome of prostate cancer patients treated with do... more The aim of this paper is to report definitive outcome of prostate cancer patients treated with dose escalation during a period of 12.5 years. From October 1999 to March 2012 we treated 1080 patients affected by prostate cancer, using External Beam Radiotherapy (EBRT). The mean age was 69.2 years. Most of patients (69%) were staged as cT2, Gleason Score (GS) < 7; the mean iPSA 18 ng/ml; the rate of clinical positive nodes was 1%. Our intention to treat was the following: for low risk patients 72 Gy; for intermediate risk patients 75.6 Gy and for high-very high risk patients 79.2 Gy in 1.8 Gy/day fractions. From 2008 we changed the fractionation scheme and the doses were the following: for low risk patients 74 Gy and for intermediate and high-very high risk patients 78 Gy in 2.0 Gy/day fractions. Whole pelvis irradiation was performed in high-very high risk patients with 43.2-50.4 Gy in 1.8 Gy per day. The mean follow-up was 81 months. For the whole population at 5 and 10 years, th...
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Papers by Michele Stasi