Wyniki wyszukiwania - Biblioteka Nauki

1

Development of an automation system for iodine-125 brachytherapy seed encapsulated by Nd:YAG laser welding

100%

Somessari S. L. , Feher A. , Sprenger F. E. , Rostelato M. E. C. M. , da Costa F. E. , Calvo W. A. P.

Nukleonika

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2011

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tom Vol. 56, No. 4

369-374

EN

The aim of this work is to develop an automation system for iodine-125 radioactive seed production by Nd:YAG laser welding, which has been used successfully in low dose rate (LDR) brachytherapy treatment. This small seed consists of a welded titanium capsule, with 0.8 mm in diameter and 4.5 mm in length, containing iodine-125 adsorbed onto a silver rod. The iodine-125 seeds are implanted into the human prostate to irradiate the tumor for cancer treatment. Nowadays, the Radiation Technology Center, at Institute for Nuclear and Energy Research, Săo Paulo, Brazil (IPEN-CNEN/SP) imports and distributes 36,000 iodine-125 seeds per year, for the clinics and hospitals in the country. However, the Brazilian market potential is now over 8,000 iodine-125 seeds per month. The local production of these iodine-125 radioactive sources became a priority for the Institute, in order to reduce the price and the problems of prostate cancer management. It will permit to spread their use to a larger number of patients in Brazil. On the other hand, the industrial automation plays an important role for iodine-125 seeds in order to increase the productivity, with high quality and assurance, avoiding human factors, implementing and operating with good manufacturing practices (GMP). The technology consists of appliance electronic and electro-mechanical parts and components to control machines and processes. The automation system technology for iodine-125 seed production developed in this work was mainly assembled employing a programmable logic controller (PLC), a stepper motor, an Nd:YAG laser welding machine and a supervisory. The statistical repeatability of correctly encapsulated sealed sources with this automation system is greater than 95 per cent.

2

Dose enhancement in brachytherapy in the presence of gold nanoparticles : a Monte Carlo study on the size of gold nanoparticles and method of modelling

100%

Ghorbani M. , Pakravan D. , Bakhshabadi M. , Meigooni A. S.

Nukleonika

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2012

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tom Vol. 57, No. 3

401-406

EN

The aim of this study was to evaluate the effect of the size of gold nanoparticles (GNPs) on dose enhancement in brachytherapy with photon emitting sources. Four photon emitting sources, 125I, 169Yb, 103Pd, and 192Ir were simulated and dose rate constant and radial dose functions were compared with published corresponding data for these sources. Dose enhancement factor in the presence of gold nanoparticles of 30 mg/ml concentration was calculated separately for nanoparticles with a diameter of 50, 100 and 200 nm. Gold nanoparticles were simulated precisely as nanospheres utilizing a lattice option in the MCNPX Monte Carlo code and the results were compared with those obtained with a simple model in which gold atoms are distributed uniformly in tumor volume as a simple mixture. Among the four mentioned sources, the dose enhancement related to 125I source is higher. Our results have shown that with gold nanoparticles of higher diameter, the level of dose enhancement is higher in the tested tumor. It has been also observed that the simple model overestimates the dose enhancement factor when compared with the precise model in which nanoparticles are defined according to the Monte Carlo code. In the energy range produced by the brachytherapy sources, the dose enhancement is higher when using brachytherapy sources with lower energy. Among the size range of gold nanoparticles used in medicine, it is predicted that nanoparticles with higher diameter can be more useful when are utilized in brachytherapy. It is also recommended that when calculating dose enhancements, a precise model be used for modelling of nanoparticles in the Monte Carlo simulations.

3

Tubing decontamination during the leak test of iodine-125 seeds

100%

Moura J. A. , Moura E. S. , Sprenger F. E. , Nagatomi H. R. , Zeituni C. A. , Feher A. , Manzoli J. E. , Souza C. D. , Rostelato M. E.

Nukleonika

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2010

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tom Vol. 55, No. 3

409-413

EN

Leak tests were made to detect any leakage of radioactive material from inside the iodine-125 seeds applied in brachytherapy. These seeds are used in prostate cancer treatment. In the quality control routine, during seed production, leak tests are performed according to the International Standard Organization – radiation protection – sealed radioactive sources – ISO-9978 standard, and require liquid transfer between recipients. Any leakage causes contamination of the liquid and tubes. The aim of this study is the establishment of decontamination routines for tubes, allowing their repeated use, in the automated assay process.

4

X-ray tube with needle-like anode

100%

Słapa M. , Straś W. , Traczyk M. , Dora J. , Snopek M. , Gutowski R. , Drabik W.

Nukleonika

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2002

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tom Vol. 47, nr 3

101-105

EN

An X-ray tube with a needle-like anode (NAXT) built in our Laboratory, its design and basic operating parameters are presented. The process of electron beam forming and influence of external and internal magnetic fields is discussed. The tube properties essential from the point of view of its application in X-ray generators as well as disadvantageous thermal effects caused by flow of heat generated in the tube target to irradiated objects are discussed. The tube is almost a point-like source of X radiation emitted into 4đ geometry; the dose rates are on the order of 1 Gy/min at the distance of 10 mm from the anode cap. Preliminary tests show the tube may be useful in brachytherapy of cancer tumors of diameter up to 30 mm. The tube may also be an interesting device in widely understood field of irradiation techniques.

5

Determination of dosimetry parameters of ADVANTAGETM 103Pd brachytherapy seed using MCNP4C computer code

88%

Ataeinia V. , Raisali G. , Sadeghi M.

Nukleonika

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2009

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tom Vol. 54, No. 3

181-187

EN

The IsoAid LLC Inc. has been introduced ADVANTAGETM 103Pd brachytherapy seed in 2006. The aim of this work is to determine the dosimetric characteristics of this seed according to AAPM’s recommendation in TG43-U1 using MCNP4C computer code. The dose rate constant has been determined to be 0.694š0.001 cGy.h–1.U–1. The radial dose function has been calculated at distances from 0.25 to 7 cm. Two-dimensional anisotropy function have been calculated at distances from 0.25 to 7 cm and at angles from 0 to 90 degrees centigrade at 10 degrees centigrade increments. The one-dimensional anisotropy function and anisotropy constant have been also calculated. The anisotropy constant in water has been calculated as 0.872š0.001. The results of this investigation are compared with the results of Meigooni et al. obtained by PTRAN code in 2006 and Sowards results obtained by PTRAN code in 2007. The comparison of the dose rate constant and the one-dimensional anisotropy function obtained from the two codes shows good agreement; also the radial dose function at distances lower than 3 cm and the two-dimensional anisotropy function at angles greater than 20 degrees centigrade are in good agreement. But, for the calculated radial dose function at distances beyond 3 cm, we observed differences between our values and Meigooni et al. and Sowards results. Also, differences between the calculated two-dimensional anisotropy function using the two codes for angles smaller than 20 degrees centigrade are considerable. The differences between the results of MCNP4C and PTRAN codes could be related to the different cross-section data libraries used in these two codes.

6

A Monte Carlo investigation of the dose distribution for new I-125 Low Dose Rate brachytherapy source in water and in different media

88%

Fardi Z. , Taherparvar P.

Polish Journal of Medical Physics and Engineering

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2019

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tom Vol. 25, Iss. 1

15--22

EN

Permanent and temporary implantation of I-125 brachytherapy sources has become an official method for the treatment of different cancers. In this technique, it is essential to determine dose distribution around the brachytherapy source to choose the optimal treatment plan. In this study, the dosimetric parameters for a new interstitial brachytherapy source I-125 (IrSeed-125) were calculated with GATE/GEANT4 Monte Carlo code. Dose rate constant, radial dose function and 2D anisotropy function were calculated inside a water phantom (based on the recommendations of TG-43U1 protocol), and inside several tissue phantoms around the IrSeed-125 capsule. Acquired results were compared with MCNP simulation and experimental data. The dose rate constant of IrSeed-125 in the water phantom was about 1.038 cGy·h−1U−1 that shows good consistency with the experimental data. The radial dose function at 0.5, 0.9, 1.8, 3 and 7 cm radial distances were obtained as 1.095, 1.019, 0.826, 0.605, and 0.188, respectively. The results of the IrSeed-125 is not only in good agreement with those calculated by other simulation with MCNP code but also are closer to the experimental results. Discrepancies in the estimation of dose around IrSeed-125 capsule in the muscle and fat tissue phantoms are greater than the breast and lung phantoms in comparison with the water phantom. Results show that GATE/GEANT4 Monte Carlo code produces accurate results for dosimetric parameters of the IrSeed-125 LDR brachytherapy source with choosing the appropriate physics list. There are some differences in the dose calculation in the tissue phantoms in comparison with water phantom, especially in long distances from the source center, which may cause errors in the estimation of dose around brachytherapy sources that are not taken account by the TG43-U1 formalism.

7

Determination of the geometry function for a brachytherapy seed, comparing MCNP results with TG-43U1 analytical approximations

88%

Raisali G. , Ghonchehnazi M. G. , Shokrani P. , Sadeghi M.

Nukleonika

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2008

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tom Vol. 53, No. 2

45-49

EN

Geometry function is the only dosimetry parameter of a brachytherapy source seed, introduced in TG-43U1 protocol which is determined using calculational methods rather than physical measurement. In order to evaluate the accuracy of point and line source approximations, for calculation of the geometry function, the MCNP computer code has been used for a typical brachytherapy seed and the results have been compared. The MCNP has been used to simulate the geometry and activity distribution of a Pd-103 seed in order to calculate the geometry function for various angles and distances from the source. The comparison of results shows that at distances close to the source, the values predicted with different methods are not in agreement. The difference between the MCNP calculations and line approximation for small angles from ? = 0 to 15° is about 27% at 0.25 cm from the seed center. This difference is so much higher for point source approximation (up to a factor of 3) even up to distances of 0.5 cm from the source. As ? increases, the difference between MCNP and approximate methods is reduced. Therefore, for small distances from brachytherapy seeds, it is recommended to calculate the geometry function using more detailed methods instead of point and linear source approximations. This will provide more accurate results for other TG-43U1 dosimetry parameters such as radial dose function or anisotropy function which for some points are calculated via interpolation or extrapolation of the available discrete dosimetry data.

8

Dosimetry of two new interstitial brachytherapy sources

88%

Saidi P. , Sadeghi M.

Polish Journal of Medical Physics And Engineering

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2011

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tom 17

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nr 3

129-141

EN

With increased demand for low 103Pd (palladium) seed sources, to treat prostate and eye cancers, new sources have been designed and introduced. This article presents the two new palladium brachytherapy sources, IR03-103Pd and IR04-103Pd that have been developed at Nuclear Science and Technology Research Institute. The dosimetry parameters such as the dose rate constant Λ, the radial dose function g(r), and the anisotropy function F(r,θ), around the sources have been characterized using Version 5 Monte Carlo radiation transport code in accordance with the update AAPM Task Group No. 43 report (TG-43U1). The results indicated the dose rate constant of 0.689±0.02 and 0.667±0.02 cGy h-1 U-1 for the IR03-103Pd and IR04-103Pd sources respectively, which are in acceptable agreement with other commercial seeds. The calculated results were compared with published results for those of other source manufacturers. However, they show an acceptable dose distribution, using for clinical applications is pending experimental dosimetry.

9

Radioisotopes for medical and industrial use during the 50-year history of the Institute of Nuclear Research

88%

Mikołajczak R. , Bazaniak Z. , Iller E.

Nukleonika

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2005

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tom Vol. 50,suppl.3

83-87

EN

The paper summarises the 50-years long history of the development of research programmes related to the practical applications of radionuclides in various fields of the Polish economy. The changing trends of interest of the potential users are reflected in the research and development activities of the Radioisotope Centre POLATOM. In the 1960's and 1970's the main areas of activity were focused on the sealed sources and radiolabelled compounds for the investigation of industrial processes. The introduction to the routine practice of the RIA and the IRMA kits for hormonal in vitro diagnostics in the 70-ties and 80-ties resulted in the general availability of this diagnostic technique in Poland. The number of radioisotopes having the required radiation type, energy and half-life is steadily increasing due to the progress in irradiation facilities and in chemical separation processes. The need for modern radiopharmaceuticals, more specific and providing higher diagnostic and therapeutic potential as an alternative to other medical modalities is reflected in the research programmes carried out and implemented currently at the Radioisotope Centre POLATOM.

10

Development and production of radioactive sources used for cancer treatment in Brazil

88%

Rostelato M. E. C. M. , Rela P. R. , Zeituni C. A. , Feher A. , Manzoli J. E. , Moura J. A. , Moura E. S. , Silva C. P. G.

Nukleonika

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2008

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tom Vol. 53, suppl. 2

99--103

EN

The number of cancer patients in Brazil is increasing and part of the patients are submitted to brachytherapy treatment using iridium-192 wire and iodine-125 radioactive seeds. The Nuclear Energy Research Institute established a programme to produce iridium-192 wire and iodine-125 radioactive seeds. With the purpose of settling a laboratory for iridium-192 sources production, a wire activation method was developed and a hot cell for the wire manipulation, quality assurance and packaging was built. The iodine-125 seeds consist of a welded titanium capsule containing iodine-125 adsorbed onto a silver rod. Concerning the setup of the local production, the following activities were carried out: superficial treatment of the silver rod, development of a process to absorb the iodine in the silver rod, welding methodology to seal the seeds, leakage and contamination test and source activity measurement.

11

A Monte Carlo study on the radio-sensitization effect of gold nanoparticles in brachytherapy of prostate by 103Pd seeds

88%

Jangjoo A. G. , Ghiasi H. , Mesbahi A.

Polish Journal of Medical Physics and Engineering

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2019

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tom Vol. 25, Iss. 2

87--92

EN

103Pd seed is being used for prostate brachytherapy. Additionally, the dose enhancement effect of gold nanoparticles (GNP) has been reported in previous studies. The aim of this study was to characterize the dosimetric effect of gold nanoparticles in brachytherapy with a 103Pd source. Two brachytherapy seeds including 103Pd source was simulated using MCNPX Monte Carlo code. The seeds’ models were validated by comparing the MC with reported results. Then, GNPs (10 nm in diameter) with a concentration of 7mg Au/g were simulated uniformly inside the prostate of a humanoid computational phantom. Additionally, the dose enhancement factor (DEF) of nanoparticles was calculated for both modeled brachytherapy seeds. A good agreement was found between the MC calculated and the reported dosimetric parameters. For both seeds, an average DEF of 23% was obtained in tumor volume for prostate brachytherapy. The application of GNPs in conjunction with 103Pd seed in brachytherapy can enhance the delivered dose to the tumor and consequently leads to better treatment outcome.

12

Analysis of the calibration results of ionization chambers for orthovoltage and brachytherapy

88%

Ulkowski P. , Bulski W. , Gwiazdowska B. , Rostkowska J.

Polish Journal of Medical Physics And Engineering

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2009

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tom 15

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nr 1

11-24

EN

An analysis of the exposure calibration coefficients for ionization chambers used for dose determination in orthovoltage radiotherapy and in brachytherapy in the Polish SSDL was performed. The coefficients were determined by calibrating the chambers in the X-ray beam of 235 kV or 290 kV and HVL of 2.5 mmCu or 4 mmCu respectively, and also in the Co-60 gamma beam. Calibration procedures followed IAEA recommendations in Report No. TECDOC 1274 and Technical Reports Series No. 277. The characteristics of the energy dependence of various types of chambers used in orthovoltage radiotherapy and in brachytherapy are presented. On the basis of the summarized data and on the energy dependence curves it was possible to conclude that: 1) in he case of calibration of the chambers for orthovoltage radiotherapy the energy dependence has to be established for the full range beam qualities; 2) in the case of calibration, of the investigated chambers, for brahytherapy with Cs-137 and Ir-192 sources, establishing of the exposure calibration factor for Co-60 is sufficient.

13

Monte Carlo study on the gold and gadolinium nanoparticles radio-sensitizer effect in the prostate 125I seeds radiotherapy

75%

Ghasemi-Jangjoo A. , Ghiasi H.

Polish Journal of Medical Physics and Engineering

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2019

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tom Vol. 25, Iss. 3

165--169

EN

Monte Carlo and TL dosimetry applied to the characterization of 125I brachytherapy with a different design with other 125I seeds. In a water phantom, lattice configuration simulated with 125I seed in the center and 10 nm gold and gadolinium nan-particle filed voxels. This simulation conducted to the characterization of the nano-particles DEF in low energy and prostate tissue. To study of the prostate brachytherapy, a humanoid computational phantom developed by CT slices applied. KTMAN-2 computational phantom contains 29 organs and 19 skeletal regions and was produced from cross-sectional x-ray computed tomography (CT slices) images. The simulated seed was 125I seed having an average energy of 28.4 keV for photons, a half-life of 59.4 days. DEF factor in the seed radiation energy (28.4 keV) DEF factor was found to be two times higher for the gold nano-particles. It was revealed than gold-nano-particles posing Z about 1.24 times higher than gadolinium led to around 200% DEF increasing in the same conditions and the nano-particles size. It was concluded that in low energy sources brachytherapy, photoelectric is dominant in the presence of relative high element nanoparticles. This leads to a high dose increasing in some micro-meters and causes a dramatic dose gradient in the vicinity of a nano-particle. This dose gradient effectively kills the tumor cells in continuous low energy irradiation in the presence of a high Z material nano-scaled particle. Application of gold nano-particles in low energy brachytherapy is recommended.

14

Leakage test evaluation used for qualification of iodine-125 seeds sealing

75%

Feher A. , Rostelato M. E. C. M. , Zeituni C. A. , Calvo W. A. P. , Somessari S. L. , Moura J. A. , Moura E. S. , Souza C. D. , Rela P. R.

Nukleonika

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2011

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tom Vol. 56, No. 4

375-379

EN

Brachytherapy is one of the possible treatments with ionizing radiation available for prostate cancer, in which small seeds containing iodine-125 radioisotope are implanted directly into the prostate. The seed consists of a sealed titanium tube containing a central silver wire with adsorbed iodine-125. The tube sealing is made with titanium at the ends, using plasma arc-welding (PAW) or laser process. This sealing must be leakage-resistant and free of cracks, therefore avoiding iodine-125 to deposit in the silver wire to escape and spread into the human body. To ensure that this problem is not occurring, rigorous leakage tests in accordance with the standard ISO-9978 should be applied. The aim of this study is to determine, implement and evaluate the leakage test to be used in the iodine-125 seeds production, in order to qualify the sealing procedure. The standard ISO-9978 presents a list of tests to be carried out according to the type of source. The preferential methods for brachytherapy sources are soaking and helium. To assess the seeds leakage, the method of immersion test at room temperature was applied. The seeds are considered leakage-free if the detected activity does not exceed 185 Bq (5 nCi). An iodine standard was prepared and its value determined in a sodium iodide detector. A liquid scintillation counter was calibrated with the standard for seed leakage tests. Forty-eight seeds were plasma arc-welded for these tests.

15

Kontrola systemu planowania leczenia w brachyterapii

75%

Wittych J. , Sobiech M.

Inżynier i Fizyk Medyczny

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2015

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tom Vol. 4, nr 4

225--228

PL

Dla każdego etapu radioterapii istnieje szereg regulacji prawnych, które mają na celu głównie poprawę jakości i bezpieczeństwa realizacji całego procesu. Ze względu na konieczność zapewnienia bezwzględnej poprawności i powtarzalności obliczeń systemy planowania leczenia stosowane w radioterapii powinny być objęty kontrolą jakości. Użycie nieprawidłowowprowadzonych danych skutkuje błędami w obliczeniach i napromienianiu pacjenta. Właściwa kontrola powinna zagwarantować możliwość wykonania optymalnego planu leczenia z wykluczeniem błędów wynikających z nieprawidłowo zdefiniowanych danych w TPS. Opublikowano kilka raportów dedykowanych zapewnieniu jakości w radioterapii, w tym również poświęconych systemom planowania leczenia [1-9]. W pracy przedstawiono podstawowe wymogi kontroli systemu planowania leczenia w brachyterapii oparte głównie na zaleceniach Bookletu No. 8 European Society for Radiotherapy and Oncology [9].

EN

There are a lot of regulations in radiotherapy dedicated to quality assurance and safety of this treatment method process. It is also recommended to control used treatment planning systems. It is necessary to be sure that the calculations and reproducibility are correct. Using incorrect data and calculations cause the mistakes in patient irradiation. The reliable quality control ought to guarantee the possibility of calculated optimal and correct treatment plan. There were published some reports for quality control (QC) in radiotherapy especially for quality control of treatment planning systems (TPS) [1-9]. The main requirements for QC of TPS used in brachytherapy, based on recommendations of Booklet No. 8 European Society for Radiotherapy and Oncology [9], were put forward in this paper.

16

Audyt dozymetryczny w brachyterapii PDR : metodologia, układy pomiarowe i wyniki

75%

Oborska-Kumaszyńska D. , Palmer A. , Matharu T.

Inżynier i Fizyk Medyczny

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2014

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tom Vol. 3, nr 1

49--52

PL

Audyty dozymetryczne prowadzone w radioterapii stanowią element procesu zapewniania jakości, który umożliwia potwierdzenie parametrów dozymetrycznych, parametrów geometrycznych systemów oraz dokładności podawania dawki. Zwykle są one prowadzone przez fizyków z jednostek zewnętrznych lub reprezentujących instytucje profesjonalistów (np. IPEM, NPL).

17

Zintegrowana linia radioterapeutyczna

75%

Miloch W. , Wtorek J.

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

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2009

|

tom Nr 26

97-100

PL

Zintegrowana linia radioterapeutyczna (ZLR) stanowi złożenie sprzętu i oprogramowania służącego do precyzyjnej radioterapii. W pierwszej kolejności w referacie wyjaśniono różnice pomiędzy teleradioterapią, a brachyterapią, które stanowią podstawowe rodzaje radioterapii. Następnie przedstawiono budowę i funkcje poszczególnych części ZLR: tomografu komputerowego, systemu planowania leczenia, symulatora i akceleratora. W dalszej kolejności przedstawiono typy komputerów sterujących ich pracą. Opis ten zawiera krótką charakterystykę konfiguracji, systemu operacyjnego, sposobu zasilania i komunikacji z pozostałymi komputerami. W referacie przedstawiono także modyfikacje ZLR, które były konieczne do uzyskania zadawalającego poziomu bezpieczeństwa napromienianych pacjentów. Na zakończenie referatu poruszono problematykę rozwoju linii terapeutycznej dla części brachyterapii jak i teleradioterapii.

EN

The Integrated Radiotherapeutic Line (IRL) constitutes composition of hardware and software for accurate radiotherapy. First, the paper explains the differences between teleradiotherapy and brachytherapy. Next, a structure of IRL is presented and functions of separate parts are described. The types of control computers are presented as well as a short technical characteristic of hardware, computer network and operating system. Another issue of the paper presents modifications of the Integrated Radiotherapeutic Line, which were necessary to achieve an appropriate level of patient’s safety. Problems arising in the course of the line integration are also presented. Finally, the paper presents issues of development of therapeutic line for brachytherapeutic part and teleradiotherapy part.

18

Współczesna brachyterapia

75%

Bulski W. , Kawczyńska M.

Inżynier i Fizyk Medyczny

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2013

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tom Vol. 2, nr 2

107--111

PL

Brachyterapia, nazywana czasami curieterapią (od nazwiska Marii Skłodowskiej- -Curie), jest terapią kontaktową. Polega na bezpośrednim napromienianiu zmian chorobowych przez umieszczenie źródła promieniowania w guzie lub jego sąsiedztwie. Podstawowym zastosowaniem brachyterapii jest leczenie zmian nowotworowych, ale jest ona wykorzystywana również w terapii chorób układu krążenia, w leczeniu keloidu, nadczynności tarczycy, czerwienicy prawdziwej, chorób gałki ocznej itd. Brachyterapię stosuje się zarówno jako samodzielne leczenie radykalne, jak i część skojarzonej terapii np. z chirurgią, teleradioterapią, leczeniem paliatywnym. Brachyterapia funkcjonuje również jako ratunkowa.

19

Zastosowanie przedoperacyjnej brachyterapii z hipertermią w leczeniu raka trzonu macicy – wstępne wyniki własne

63%

Śpiewankiewicz B. , Piotrkowicz N. , Nalewczyńska A. , Timorek-Lemieszczuk A.

Current Gynecologic Oncology

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2010

|

tom 8

|

nr 1

21-26

EN

Endometrial cancer became recently the most frequently diagnosed female genital malignancy in highly developed countries. In 2003 in Poland, 3953 new cases were diagnosed (standardized coefficient: 13.00) and 783 women died thereof (standardized coefficient: 2.2). In the treatment of malignant tumors, heat has been used since Antiquity. Beneficial effect of hyperthermia relies on direct cytotoxic effect, manifesting after elevation of tissue temperature to 41-43°C. Studies performed hitherto combined hyperthermia with standard therapeutic modalities – radiotherapy and chemotherapy. The aim of this paper was to assess the effectiveness of treatment, based on determination of degree of destruction of tumor cells as assessed by histological studies, evaluation of toxicity of the treatment, assessment of quality of life one year after completion of treatment protocol and determination of 3-years’ survival rate. To date, the study encompassed 18 patients with the diagnosis of clinical stage I endometrial cancer, based on histological study of scrapings from uterine cavity and cervical canal. In 14 patients, study of material obtained at fractionated curettage of cervical canal and uterine cavity revealed endometrial cancer of the endometrioid type, in 1 – papillary type and in 3 – no histological tumor type could be determined. Surgery was performed 15-85 days (mean: 34.88 days) after completion of brachytherapy combined with hyperthermia. Based on histological study of surgical specimens, in 6 out of 18 patients (33.3%) no tumor tissue could be detected. In 2 cases (11.1%) after surgery a FIGO stage IIIC cancer was diagnosed in view of presence of metastases to inguinal lymph nodes. These patients were referred for adjuvant teleradiotherapy. In the remaining 10 cases (55.5%), FIGO stage I endometrial cancer was diagnosed. Based on the results obtained, the following conclusions were reached: 1) No complications directly associated with neoadjuvant brachytherapy with hyperthermia were noticed in any of our patients. 2) Alterations detected at surgery, purportedly associated with the treatment performed, did not compromise course or scope of surgery. 3) In 1/3 of our patients, examination of surgical specimens failed to reveal malignant tissue.

PL

W ostatnich latach w krajach o wysokim poziomie rozwoju cywilizacyjnego rak trzonu macicy stał się najczęściej rozpoznawanym nowotworem narządów płciowych kobiety. W Polsce w 2003 roku odnotowano 3953 zachorowania na ten nowotwór (współczynnik standaryzowany – 13,00) oraz 783 zgony (współczynnik standaryzowany – 2,2). W terapii nowotworów złośliwych ciepło wykorzystuje się od dawna. Podstawą działania hipertermii jest bezpośredni efekt cytotoksyczny, ujawniający się przy podwyższeniu temperatury do 41-43°C. W przeprowadzanych dotąd badaniach hipertermię łączono ze standardowo stosowanymi metodami leczenia – radioterapią i chemioterapią. Celem pracy była ocena efektywności leczenia, dokonana na podstawie określenia stopnia uszkodzenia nowotworu w oparciu o badanie histologiczne, ocena toksyczności leczenia, ocena jakości życia po roku od zakończenia leczenia oraz ocena 3-letniego przeżycia. Dotychczas do badania włączono 18 chorych, u których rozpoznano raka trzonu macicy w I stopniu klinicznego zaawansowania na podstawie badania histologicznego wyskrobin z jamy macicy i kanału szyjki. U 14 badanych kobiet w materiale uzyskanym po frakcjonowanym wyłyżeczkowaniu kanału szyjki i jamy macicy rozpoznano raka endometrium o typie endometrioidalnym, u jednej typ brodawkowaty, zaś u 3 chorych nie określono postaci histologicznej nowotworu. Zabieg operacyjny wykonywano w odstępie od 15 do 85 dni (średnio 34,88 dnia) od zakończenia brachyterapii skojarzonej z hipertermią. Na podstawie przeprowadzonego badania histologicznego materiału pooperacyjnego u 6 z 18 pacjentek (33,3%) nie stwierdzono utkania nowotworu. W 2 przypadkach (11,1%) pooperacyjnie rozpoznano IIIC stopień klinicznego zaawansowania według FIGO, gdyż wykryto przerzuty raka do węzłów chłonnych biodrowych. Pacjentki te zostały zakwalifikowane do uzupełniającej teleradioterapii. U pozostałych 10 kobiet (55,5%) rozpoznano I stopień zaawansowania według klasyfikacji chirurgiczno-patologicznej FIGO. Na podstawie przeprowadzonych badań wysunięto następujące wstępne wnioski: 1) Bezpośrednio po przedoperacyjnej brachyterapii z hipertermią nie odnotowano u pacjentek powikłań. 2) Śródoperacyjnie obserwowane zmiany, związane z przebytym leczeniem, nie miały wpływu na przebieg zabiegu operacyjnego i jego zakres. 3) U 33,3% chorych w materiale pooperacyjnym nie stwierdzono rozrostu złośliwego.

20

Zastosowanie radioterapii śródoperacyjnej w nowotworach wywodzących się z narządów płciowych kobiet

63%

Biedka M. , Śpiewankiewicz B.

Current Gynecologic Oncology

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2012

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tom 10

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nr 3

215-225

EN

Intraoperative radiotherapy is an innovative boosting technique enabling administration of single high dose of radiation, usually combined with external beam radiotherapy following surgery, used in the treatment of both primary and recurrent lesions. Such an approach offers several radiobiological, physical and clinical benefits. One of them is the option to irradiate selected anatomical areas identified during surgery as high-risk and/or residual tumor sites while protecting adjacent normal tissues, major nerve trunks and blood vessels, which may be displaced out of the irradiated field or covered with special shields. Key benefits of intraoperative radiotherapy include delivery of high total dose of radiation, superior local control and greater influence on overall survival. Available techniques of intraoperative radiotherapy include brachytherapy, generating high energy photon radiation using temporary or permanent applicators and mobile linear accelerators, which are the main source of electrons. Compared with conventional brachytherapy or teleradiotherapy, intraoperative radiotherapy offers several benefits including: ability to irradiate resection margins in order to reduce the risk of recurrence from tumor cells remaining the resection plane and reduction of risk of “geographical error”, enabling real-time inspection or palpation of surgical site. Furthermore, intraoperative radiotherapy makes possible reduction of radiation dose delivered to the skin, subcutaneous tissue and bones, while a large single dose provides an enhanced biological effect as compared with conventional radiotherapy. The aim of this paper was to point out types of female genital tumors which may be treated using intraoperative radiotherapy.

PL

Śródoperacyjna radioterapia jest innowacyjną techniką umożliwiającą podanie pojedynczej wysokiej dawki radioterapii, najczęściej w leczeniu skojarzonym z teleterapią po leczeniu operacyjnym, wykorzystywaną do leczenia zarówno zmian pierwotnych, jak i nawrotowych. Podejście to ma kilka zalet od strony radiobiologicznej, fizycznej i klinicznej. Jedną z nich jest możliwość napromieniania, w trakcie leczenia chirurgicznego, wybranych obszarów anatomicznych zidentyfikowanych jako obszary wysokiego ryzyka i/lub guza resztkowego, z jednoczesną ochroną prawidłowych tkanek, dużych nerwów, naczyń, które mogą być przesunięte z obszaru napromieniania lub zakryte specjalnymi osłonami. Do istotnych korzyści śródoperacyjnej radioterapii należą podanie wysokiej całkowitej dawki z radioterapii, zwiększona kontrola miejscowa, a także większy wpływ na całkowite przeżycia. Wśród możliwych technik radioterapii śródoperacyjnej wymienia się brachyterapię generującą energię fotonową o wysokiej mocy dawki z wykorzystaniem tymczasowych lub stałych aplikatorów oraz zastosowanie mobilnych przyspieszaczy liniowych będących głównie źródłem elektronów. W porównaniu z brachyterapią czy teleterapią radioterapia śródoperacyjna ma kilka istotnych zalet, między innymi w trakcie zabiegu marginesy po resekcji guza mogą być napromienione celem zmniejszenia prawdopodobieństwa pozostawienia komórek nowotworowych w linii cięcia, ponadto ogranicza się ryzyko błędu „geograficznego”, dzięki możliwości obejrzenia w czasie rzeczywistym lub palpacji loży pooperacyjnej. Radioterapia śródoperacyjna wpływa także na zmniejszenie dawki na skórę, tkankę podskórną i kości, a pojedyncza dawka daje większy efekt radiobiologiczny w porównaniu z konwencjonalną radioterapią. Celem pracy jest wskazanie nowotworów narządu rodnego, które mogą być leczone z wykorzystaniem śródoperacyjnej radioterapii.