Carcinoma of the vulva is relatively rare, making up 3% to 4% of all primary genital cancer. It i... more Carcinoma of the vulva is relatively rare, making up 3% to 4% of all primary genital cancer. It is a disease of the elderly. The Authors treated from 1976 to 1987 twenty-one patients with locally advanced squamous vulvar cancer (6 T2; 12 T3; 3 T4). Nine of these patients were submitted to radiotherapy alone; the others were treated with a combination of surgery and postoperative radiation. Two and five years disease-free survival rate was 33% and 19%. The rate of radiotherapy sequelae has been low, because the patients were treated with the concentional 200 cGy per day or similar fractionation schemes. Disease-free survival rate was better in the subgroup of patients who underwent to combined surgery and post-operative radiation therapy. These results are discussed in comparison with others series in literature.
ABSTRACT A careful theoretical and experimental evaluation has been made in order to estimate the... more ABSTRACT A careful theoretical and experimental evaluation has been made in order to estimate the neutron dose equivalent for critical organs of patients treated by gamma ray therapy. The machine employed in these studies is the linear electron accelerator MD Class Mevatron, Siemens, installed at the S. Giovanni Battista A.S. Hospital in Torino (Italy) and used for tumour therapy. A calculational method was developed, using two suitable 3D Monte Carlo computer codes: the EGS4 code (Electron Gamma Shower), which evaluates bremsstrahlung gamma rays and photo-neutron production in the accelerator head and the MCNP code (Monte Carlo Neutron and Photon Transport), which simulates the neutron transport and evaluates the organ dose equivalents. In addition, two sets of measurements were made during treatment sessions with 2 Gy therapeutic gamma dose: (a) by means of thermoluminescence dosemeters TLD-600 and TLD-700 placed at various depths inside an anthropomorphic phantom in positions corresponding to the organs; (b) in vivo by albedo neutron personal dosemeters UD-802, National Panasonic, positioned on the patients according to the organs. The agreement between experimental and theoretical data is good. The neutron organ dose equivalents are by no means negligible; for instance H T varies from 2.65 mSv on the thyroid to 42.02 mSv on testes, if normalised to one Gy of maximum absorbed dose in the pelvis, of the primary gamma beam if 15 MeV maximum energy (10 cm x 10 cm field size and source-skin distance of 1 m).
Purpose: Radiotherapy post-lumpectomy with two coplanar tangent beams is the standard treatment f... more Purpose: Radiotherapy post-lumpectomy with two coplanar tangent beams is the standard treatment for women with early stage breast cancer. Despite the use of wedges as tissue compensators, the resultant plans often contains a significant dose gradient and 'hot spots' in excess of 15% or more of prescribed dose. In recent years a field-in-field (FIF) dose-compensation technique, which use two standard tangent fields and one or two (rarely three) small beams within these, was developed. It allows to obtain a more uniform dose throughout the target volume in the majority of cases but not in all. This study presents our experience to develop optimal intensity modulated radiation therapy (IMRT) techniques to be applied clinically in those cases where the traditional technique with two tangent fields or its variant field in field (FIF) are unable to achieve a satisfactory planning target volumes (PTVs) coverage and dose objectives to the organs at risk (OARs). Methods: We investigated two pure IMRT plans (named 3F-IMRT and 4F-IMRT) and a hybrid one (H-IMRT). Treatment plans were performed for 7 left-sided and 4 right-sided breasts using simultaneously integrated boost (SIB) planned technique with inverse optimization. Results were compared with those obtained with FIF technique. Dose prescribed was 45 Gy/20 fractions to the breast and 50 Gy /20 fractions to the lumpectomy cavity delivered in 5 fr/week. Dose-volume histograms were generated and parameters as target dose coverage, conformity and homogeneity as well as OARs dose distribution were analyzed. Finally the secondary cancer risk to contralateral breast due to radiation was evaluated as a further parameter for the choice of the optimal plan. Results: Compared to the FIF, the three IMRT plans provided the same target coverage and a better dose conformation, but a worst dose homogeneity of the boost target. The volume of the OARs, receiving higher doses than 15 Gy was reduced but was increased the volume receiving low doses. This causes the increase of the risk of radiation induced cancer, especially for the contralateral breast. For this organ, the highest value of the excess absolute risk (EAR) was associated to the 4F-IMRT, while the lower, to the FIF. Conclusion: The intensity-modulated radiation therapy techniques 5F-IMRT and 4F-IMRT were the best to be applied clinically in those cases, where the traditional technique of irradiation of the breast is unable to achieve the PTVs coverage and dose objectives to the OARs. However, all the IMRT techniques showed an increased volume of healthy tissues receiving low doses, so they should not be used in extensive manner and in particular should be avoided in the cases of young women due to the excess of risk to develop a secondary cancer.
Nuclear Instruments and Methods in Physics Research, 1984
... 22 (1973), p. 281. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (2). 4... more ... 22 (1973), p. 281. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (2). 4. RO Bell, FV Wald, C. Canali, F. Nava and G. Ottaviani IEEE Trans. Nucl. ... Full Text via CrossRef. 7. J. Llacer, MK Watt, M. Schieber, R. Carlston and W. Schnepple IEEE Trans. Nucl. Sci. ...
The authors describe the interaction of electrons with tissues, the characteristics of depth isod... more The authors describe the interaction of electrons with tissues, the characteristics of depth isodose curves with sharp dose fall-off. These characteristics reduce the utilization of electron therapy only for tumors situated some 5 cm depth below the skin surface and with regular surface. The authors report their experience from 1978 in the treatment of vulvar carcinoma, chest-wall recurrences from breast carcinoma, and cutaneous lymphomas. All these neoplastic diseases were treated with electron beam of adequate energy. Initially betatron was used, successively a linear accelerator (Siemens) about for two years. Results obtained in the treatment of vulvar carcinoma are reported. Two and five years disease free survival rates was respectively 33% and 19% (it is remarked the importance of prophylactic treatment on inguinal lymphnodes). Local control observed in 44 patients with cutaneous lymphomas was 85% until three years; a greater number of recurrences was observed in centrocytic-c...
This study was aimed at assessing whether c-DDP administration immediately before radiotherapy co... more This study was aimed at assessing whether c-DDP administration immediately before radiotherapy could increase frequency and duration of objective responses, as well as survival, in patients affected with locally advanced stages of squamous carcinomas of the head and neck. All patients had already undergone two induction cycles according to the CABO schedule. Ninety-six of 108 treated patients could be evaluated. Treatment schedule consisted in: 1) randomized distribution of patients into two groups before induction chemotherapy; 2) two cycles of induction chemotherapy according to the CABO schedule in all patients; 3) radiation therapy: the patients in group A were given 5 mg/mq of i.v. cisplatin, 30-60 minutes before each session. The results from the two groups were compared and no significant differences were observed regarding objective response (82.5% in group A vs. 86% in group B), response duration and overall survival rates. Even though toxicity was higher in the patients in...
The development of large area xenon drift chambers as imaging systems for the advanced Gamma-Ray ... more The development of large area xenon drift chambers as imaging systems for the advanced Gamma-Ray Astronomy Telescope Experiment (AGATE), sensitive in the energy range 20 MeV - 100 GeV, is presented here. AGATE is visualized as the successor to the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory, and will add to the wide range of important results currently being obtained by EGRET. Experiments were carried out with a laboratory prototype consisting of a stack of sixteen 1/2m X 1/2m active ...
Simulations of spectroscopic performances of CdTe detectors by means of a Monte Carlo code have b... more Simulations of spectroscopic performances of CdTe detectors by means of a Monte Carlo code have been recently reported. The computer code was demonstrated to be an extremely useful tool in simulating the spectral response of CdTe to gamma rays and in understanding the detailed effects of physical and electronic parameters on the experimental performances. In the present work, the attention
A study concerning the use of a 1 cm2 p-i-n (alpha) -Si:H structure coupled to a 1 cm3 CsI(Tl) sc... more A study concerning the use of a 1 cm2 p-i-n (alpha) -Si:H structure coupled to a 1 cm3 CsI(Tl) scintillator is presented and discussed as a survey meter in the range from 20 to 125 keV x ray peak energy. A particular mesa etch, coupled with standard photolithography, lowers dark current in the pA region, allowing the use of the
Two detectors for fast two-dimensional (2D) and quasi-three-dimensional (quasi-3D) verification o... more Two detectors for fast two-dimensional (2D) and quasi-three-dimensional (quasi-3D) verification of the dose delivered by radiotherapy beams have been developed at University and Istituto Nazionale di Fisica Nucleare (INFN) of Torino. The Magic Cube is a stack of strip-segmented ionization chambers interleaved with water-equivalent slabs. The parallel plate ionization chambers have a sensitive area of 24 x 24 cm2, and consist of 0.375 cm wide and 24 cm long strips. There are a total of 64 strips per chamber. The Magic Cube has been tested with the clinical proton beam at Loma Linda University Medical Centre (LLUMC), and was shown to be capable of fast and precise quasi-3D dose verification. The Pixel Ionization Chamber (PXC) is a detector with pixel anode segmentation. It is a 32 x 32 matrix of 1024 cylindrical ionization cells arranged in a square 24 x 24 cm2 area. Each cell has 0.4 cm diameter and 0.55 cm height, at a pitch of 0.75 cm separates the centre of adjacent cells. The sen...
A pixel-segmented ionization chamber has been designed and built by Torino University and INFN. T... more A pixel-segmented ionization chamber has been designed and built by Torino University and INFN. The detector features a 24 x 24 cm2 active area divided in 1024 independent cylindrical ionization chambers and can be read out in 500 micros without introducing dead time; the digital charge quantum can be adjusted between 100 fC and 800 fC. The sensitive volume of each single ionization chamber is 0.07 cm3. The purpose of the detector is to ease the two-dimensional (2D) verifications of fields with complex shapes and large gradients. The detector was characterized in a PMMA phantom using 60Co and 6 MV x-ray photon beams. It has shown good signal linearity with respect to dose and dose rate to water. The average sensitivity of a single ionization chamber was 2.1 nC/Gy, constant within 0.5% over one month of daily measurements. Charge collection efficiency was 0.985 at the operating polarization voltage of 400 V and 3.5 Gy/min dose rate. Tissue maximum ratio and output factor have been co...
ABSTRACT Hole mobility along the layers in HgI2 has been measured for the first time by the nucle... more ABSTRACT Hole mobility along the layers in HgI2 has been measured for the first time by the nuclear techniques using alpha particles and by cutting the sample perpendicularly to the layers. The value of the hole drift mobility is in agreement with previous results obtained by Photo-Electro-Magnetic (PEM) effect and it is much higher than hole drift mobility along the c-axis.
Diamond is a very attractive material for use as a radiation detector due to its inertness, radia... more Diamond is a very attractive material for use as a radiation detector due to its inertness, radiation hardness and tissue equivalence. The development of diamond radiation detectors was limited by the availability of good and reproducible natural samples. The advent of chemical vapour deposition techniques has allowed these drawbacks to be overcome and applications of CVD diamond in X-ray and
Carcinoma of the vulva is relatively rare, making up 3% to 4% of all primary genital cancer. It i... more Carcinoma of the vulva is relatively rare, making up 3% to 4% of all primary genital cancer. It is a disease of the elderly. The Authors treated from 1976 to 1987 twenty-one patients with locally advanced squamous vulvar cancer (6 T2; 12 T3; 3 T4). Nine of these patients were submitted to radiotherapy alone; the others were treated with a combination of surgery and postoperative radiation. Two and five years disease-free survival rate was 33% and 19%. The rate of radiotherapy sequelae has been low, because the patients were treated with the concentional 200 cGy per day or similar fractionation schemes. Disease-free survival rate was better in the subgroup of patients who underwent to combined surgery and post-operative radiation therapy. These results are discussed in comparison with others series in literature.
ABSTRACT A careful theoretical and experimental evaluation has been made in order to estimate the... more ABSTRACT A careful theoretical and experimental evaluation has been made in order to estimate the neutron dose equivalent for critical organs of patients treated by gamma ray therapy. The machine employed in these studies is the linear electron accelerator MD Class Mevatron, Siemens, installed at the S. Giovanni Battista A.S. Hospital in Torino (Italy) and used for tumour therapy. A calculational method was developed, using two suitable 3D Monte Carlo computer codes: the EGS4 code (Electron Gamma Shower), which evaluates bremsstrahlung gamma rays and photo-neutron production in the accelerator head and the MCNP code (Monte Carlo Neutron and Photon Transport), which simulates the neutron transport and evaluates the organ dose equivalents. In addition, two sets of measurements were made during treatment sessions with 2 Gy therapeutic gamma dose: (a) by means of thermoluminescence dosemeters TLD-600 and TLD-700 placed at various depths inside an anthropomorphic phantom in positions corresponding to the organs; (b) in vivo by albedo neutron personal dosemeters UD-802, National Panasonic, positioned on the patients according to the organs. The agreement between experimental and theoretical data is good. The neutron organ dose equivalents are by no means negligible; for instance H T varies from 2.65 mSv on the thyroid to 42.02 mSv on testes, if normalised to one Gy of maximum absorbed dose in the pelvis, of the primary gamma beam if 15 MeV maximum energy (10 cm x 10 cm field size and source-skin distance of 1 m).
Purpose: Radiotherapy post-lumpectomy with two coplanar tangent beams is the standard treatment f... more Purpose: Radiotherapy post-lumpectomy with two coplanar tangent beams is the standard treatment for women with early stage breast cancer. Despite the use of wedges as tissue compensators, the resultant plans often contains a significant dose gradient and 'hot spots' in excess of 15% or more of prescribed dose. In recent years a field-in-field (FIF) dose-compensation technique, which use two standard tangent fields and one or two (rarely three) small beams within these, was developed. It allows to obtain a more uniform dose throughout the target volume in the majority of cases but not in all. This study presents our experience to develop optimal intensity modulated radiation therapy (IMRT) techniques to be applied clinically in those cases where the traditional technique with two tangent fields or its variant field in field (FIF) are unable to achieve a satisfactory planning target volumes (PTVs) coverage and dose objectives to the organs at risk (OARs). Methods: We investigated two pure IMRT plans (named 3F-IMRT and 4F-IMRT) and a hybrid one (H-IMRT). Treatment plans were performed for 7 left-sided and 4 right-sided breasts using simultaneously integrated boost (SIB) planned technique with inverse optimization. Results were compared with those obtained with FIF technique. Dose prescribed was 45 Gy/20 fractions to the breast and 50 Gy /20 fractions to the lumpectomy cavity delivered in 5 fr/week. Dose-volume histograms were generated and parameters as target dose coverage, conformity and homogeneity as well as OARs dose distribution were analyzed. Finally the secondary cancer risk to contralateral breast due to radiation was evaluated as a further parameter for the choice of the optimal plan. Results: Compared to the FIF, the three IMRT plans provided the same target coverage and a better dose conformation, but a worst dose homogeneity of the boost target. The volume of the OARs, receiving higher doses than 15 Gy was reduced but was increased the volume receiving low doses. This causes the increase of the risk of radiation induced cancer, especially for the contralateral breast. For this organ, the highest value of the excess absolute risk (EAR) was associated to the 4F-IMRT, while the lower, to the FIF. Conclusion: The intensity-modulated radiation therapy techniques 5F-IMRT and 4F-IMRT were the best to be applied clinically in those cases, where the traditional technique of irradiation of the breast is unable to achieve the PTVs coverage and dose objectives to the OARs. However, all the IMRT techniques showed an increased volume of healthy tissues receiving low doses, so they should not be used in extensive manner and in particular should be avoided in the cases of young women due to the excess of risk to develop a secondary cancer.
Nuclear Instruments and Methods in Physics Research, 1984
... 22 (1973), p. 281. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (2). 4... more ... 22 (1973), p. 281. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (2). 4. RO Bell, FV Wald, C. Canali, F. Nava and G. Ottaviani IEEE Trans. Nucl. ... Full Text via CrossRef. 7. J. Llacer, MK Watt, M. Schieber, R. Carlston and W. Schnepple IEEE Trans. Nucl. Sci. ...
The authors describe the interaction of electrons with tissues, the characteristics of depth isod... more The authors describe the interaction of electrons with tissues, the characteristics of depth isodose curves with sharp dose fall-off. These characteristics reduce the utilization of electron therapy only for tumors situated some 5 cm depth below the skin surface and with regular surface. The authors report their experience from 1978 in the treatment of vulvar carcinoma, chest-wall recurrences from breast carcinoma, and cutaneous lymphomas. All these neoplastic diseases were treated with electron beam of adequate energy. Initially betatron was used, successively a linear accelerator (Siemens) about for two years. Results obtained in the treatment of vulvar carcinoma are reported. Two and five years disease free survival rates was respectively 33% and 19% (it is remarked the importance of prophylactic treatment on inguinal lymphnodes). Local control observed in 44 patients with cutaneous lymphomas was 85% until three years; a greater number of recurrences was observed in centrocytic-c...
This study was aimed at assessing whether c-DDP administration immediately before radiotherapy co... more This study was aimed at assessing whether c-DDP administration immediately before radiotherapy could increase frequency and duration of objective responses, as well as survival, in patients affected with locally advanced stages of squamous carcinomas of the head and neck. All patients had already undergone two induction cycles according to the CABO schedule. Ninety-six of 108 treated patients could be evaluated. Treatment schedule consisted in: 1) randomized distribution of patients into two groups before induction chemotherapy; 2) two cycles of induction chemotherapy according to the CABO schedule in all patients; 3) radiation therapy: the patients in group A were given 5 mg/mq of i.v. cisplatin, 30-60 minutes before each session. The results from the two groups were compared and no significant differences were observed regarding objective response (82.5% in group A vs. 86% in group B), response duration and overall survival rates. Even though toxicity was higher in the patients in...
The development of large area xenon drift chambers as imaging systems for the advanced Gamma-Ray ... more The development of large area xenon drift chambers as imaging systems for the advanced Gamma-Ray Astronomy Telescope Experiment (AGATE), sensitive in the energy range 20 MeV - 100 GeV, is presented here. AGATE is visualized as the successor to the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma-Ray Observatory, and will add to the wide range of important results currently being obtained by EGRET. Experiments were carried out with a laboratory prototype consisting of a stack of sixteen 1/2m X 1/2m active ...
Simulations of spectroscopic performances of CdTe detectors by means of a Monte Carlo code have b... more Simulations of spectroscopic performances of CdTe detectors by means of a Monte Carlo code have been recently reported. The computer code was demonstrated to be an extremely useful tool in simulating the spectral response of CdTe to gamma rays and in understanding the detailed effects of physical and electronic parameters on the experimental performances. In the present work, the attention
A study concerning the use of a 1 cm2 p-i-n (alpha) -Si:H structure coupled to a 1 cm3 CsI(Tl) sc... more A study concerning the use of a 1 cm2 p-i-n (alpha) -Si:H structure coupled to a 1 cm3 CsI(Tl) scintillator is presented and discussed as a survey meter in the range from 20 to 125 keV x ray peak energy. A particular mesa etch, coupled with standard photolithography, lowers dark current in the pA region, allowing the use of the
Two detectors for fast two-dimensional (2D) and quasi-three-dimensional (quasi-3D) verification o... more Two detectors for fast two-dimensional (2D) and quasi-three-dimensional (quasi-3D) verification of the dose delivered by radiotherapy beams have been developed at University and Istituto Nazionale di Fisica Nucleare (INFN) of Torino. The Magic Cube is a stack of strip-segmented ionization chambers interleaved with water-equivalent slabs. The parallel plate ionization chambers have a sensitive area of 24 x 24 cm2, and consist of 0.375 cm wide and 24 cm long strips. There are a total of 64 strips per chamber. The Magic Cube has been tested with the clinical proton beam at Loma Linda University Medical Centre (LLUMC), and was shown to be capable of fast and precise quasi-3D dose verification. The Pixel Ionization Chamber (PXC) is a detector with pixel anode segmentation. It is a 32 x 32 matrix of 1024 cylindrical ionization cells arranged in a square 24 x 24 cm2 area. Each cell has 0.4 cm diameter and 0.55 cm height, at a pitch of 0.75 cm separates the centre of adjacent cells. The sen...
A pixel-segmented ionization chamber has been designed and built by Torino University and INFN. T... more A pixel-segmented ionization chamber has been designed and built by Torino University and INFN. The detector features a 24 x 24 cm2 active area divided in 1024 independent cylindrical ionization chambers and can be read out in 500 micros without introducing dead time; the digital charge quantum can be adjusted between 100 fC and 800 fC. The sensitive volume of each single ionization chamber is 0.07 cm3. The purpose of the detector is to ease the two-dimensional (2D) verifications of fields with complex shapes and large gradients. The detector was characterized in a PMMA phantom using 60Co and 6 MV x-ray photon beams. It has shown good signal linearity with respect to dose and dose rate to water. The average sensitivity of a single ionization chamber was 2.1 nC/Gy, constant within 0.5% over one month of daily measurements. Charge collection efficiency was 0.985 at the operating polarization voltage of 400 V and 3.5 Gy/min dose rate. Tissue maximum ratio and output factor have been co...
ABSTRACT Hole mobility along the layers in HgI2 has been measured for the first time by the nucle... more ABSTRACT Hole mobility along the layers in HgI2 has been measured for the first time by the nuclear techniques using alpha particles and by cutting the sample perpendicularly to the layers. The value of the hole drift mobility is in agreement with previous results obtained by Photo-Electro-Magnetic (PEM) effect and it is much higher than hole drift mobility along the c-axis.
Diamond is a very attractive material for use as a radiation detector due to its inertness, radia... more Diamond is a very attractive material for use as a radiation detector due to its inertness, radiation hardness and tissue equivalence. The development of diamond radiation detectors was limited by the availability of good and reproducible natural samples. The advent of chemical vapour deposition techniques has allowed these drawbacks to be overcome and applications of CVD diamond in X-ray and
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