Versnellende deeltjes (3D - PLATO) verhogen effect van bestralen bij prostaatkanker. een overzichtstudie van beschikbare methoden en hun effectiviteit van radiotherapie

3 oktober 2011: ik ben kanker-actueel aan het herzien en kwam onderstaand artikel uit 2001 tegen. Nu blijkt dat deze manier van bestralen veel navolging heeft gekregen en niet alleen met de hieronder beschreven PLATO methode. Hier het abstract van een van de meest recentere studies naar deze vorm van radiotherapie. Als u hier klikt kunt u het volledige studierapport met vergelijkende statistieken enz. gratis inzien.

Het abstract:

DOI: 10.4103/0973-1482.82917 Prabhakar R, Rath GK, Haresh KP, Manoharan N, Laviraj MA, Rajendran M, Julka PK. A study on the tumor volume computation between different 3D treatment planning systems in radiotherapy. J Can Res Ther [serial online] 2011 [cited 2011 Oct 3];7:168-73. Available from: http://www.cancerjournal.net/text.asp?2011/7/2/168/82917

A study on the tumor volume computation between different 3D treatment planning systems in radiotherapy

Abstract

Background: Tumor volume plays a crucial role in the survival and local control of the patients treated with radiotherapy. The dose volume histogram also depends on the accuracy of the tumor delineation.
Aims: The main aim is to study the variation observed in the computation of the target volume with different treatment planning systems and treatment sites.
Materials and Methods: Sixty patients of different treatment sites which include brain, retinoblastoma, head and neck, lung, gall bladder, liver, anal canal etc, were selected for this study. The tumor volume was delineated on the Eclipse treatment planning systems and CT datasets and DICOM-RT structure sets were transferred to Pinnacle, Oncentra, Plato, Precise, Ergo++, and Tomocon contouring workstations. The recomputed volume from these planning systems was compared with the reference volume obtained from Eclipse. Similarly, the accuracy in generating PTV from CTV was also assessed with different planning systems for 5 and 10 mm.
Statistical Analysis Used: SPSS 10.0 was used for analysis.
Results: The overall comparison of the volume with different planning systems showed that Pinnacle calculated relatively larger volume followed by Plato as compared to Eclipse, whereas TOMOCON, Ergo ++, and Oncentra showed reduced volume. As far as the variation in CTV to PTV volume is concerned, pinnacle showed a relatively higher volume as compared to the Eclipse planning systems.
Conclusion: The study shows that all the treatment planning systems showed variation in computing the tumor volume and the CTV to PTV generation also varied with the planning systems.

juni 2001: Het Nederlandse bedrijf Nucletron claimt een nieuwe machine te hebben uitgevonden die een effectievere vorm van bestraling bij prostaatkanker mogelijk maakt (PLATO behandeling) . De nieuwe methode houdt in dat tijdens de brachy (is inwendige bestraling met radioactieve staafjes) de bestraling wordt begeleid met een 'versneller' waardoor de tumorcellen worden oververhit en daardoor nog meer kankercellen worden vernietigd en het omliggende weefsel wordt gespaard.

We hebben nadere informatie gevraagd bij Nucletron wanneer deze methode in de Nederlandse ziekenhuizen kan worden toegepast en zullen u van hun antwoord op de hoogte houden. Zie brief met uitleg van manager Brachytherapie Nucletron als antwoord op onze vragen op pagina kankersoorten prostaatkanker algemeen en prostaatkanker bevriezingstechniek.. Zie verder volgend persbericht van Nucletron.

- Spanish Hospital Pioneers Advanced Radiation Therapy Cancer Treatment --

VEENENDAAL, The Netherlands, June 28 /CNW/ -- Nucletron BV, an
international leader in radiotherapy, announces the first clinical treatments
combining the advanced inverse planning features of the PLATO treatment
planning system with a Siemens linear accelerator.
    The Radiotherapy Department of the Virgen Macarena Hospital chose precise
Intensity Modulation Radiation Therapy (IMRT) for the treatment of a patient
with prostate cancer. The IMRT technique allows the hospital to improve local
tumor control and decrease adverse side effects of the treatment. The
treatment was designed using inverse treatment planning on the Nucletron PLATO
system, allowing higher radiation dose to be given to the tumor and minimising
dose to radiation sensitive organs. IMRT is of interest in the treatment of
prostate cancer because of the proximity of radiation sensitive organs that
are difficult to avoid using conventional treatments.
    The treatment was the first to use the Nucletron planning system linked
with a Primus linear accelerator from Siemens. The linear accelerator is
equipped with a multi-leaf collimator (MLC) which shapes and modulates the
intensity of the radiation beam during the treatment. The complex sequence of
movements of the MLC is calculated on the PLATO planning system and
transferred electronically to the control system of the linear accelerator.
    In IMRT, the treatment radiation beams are divided into a series of small
fields, whose irregular shape is determined by the multi-leaf collimator.
Accurately modeling the combined effect of many small, irregular fields in
order to provide independent verification of the PLATO treatment planning
system and treatment on the linear accelerator is a major step towards the
routine application of this new treatment method.
    The clinical implementation of the IMRT technique, with a satisfactory
degree of confidence, has been possible thanks to the scientific background of
the research group of the Sevilla University (Medical Physiology and Biophysic
Department) in close collaboration with the Virgen Macarena Hospital. This
team has a wide experience on dosimetrical verification of complex
Radiotherapy treatments by means of Monte Carlo calculation. Prof.
Sanchez-Doblado and Dr. Leal said, "IMRT has been an exciting challenge to be
checked in the new ITP module. The agreement between PLATO and Monte Carlo
simulation has been very gratifying."
    Before performing treatments of this complexity, the hospital performed
extensive verification tests on all elements of the planning and treatment
chain. Dr. Rafael Arrans and Dr. Rosello of the Radiophysics Department said,
"This has been possible after verification of the high level of
agreement between the calculation results given by the planning system and
experimental methods carried out on anthropomorphic phantoms and simulated by
Monte Carlo technique. A discrepancy of only 0.6% was found on the reference
point between the dose proposed by PLATO and the measurement of an ion
chamber."
    The close agreement between calculated and measured doses is in agreement
with studies at other hospitals using Nucletron PLATO in combination with
linear accelerators manufactured by Elekta and Varian.
    Dr. Luis Errazquin and Dr. Areste from the Radiotherapy Department
commented further, "In spite of its complexity, the application of this
technique has not been so time-consuming as to affect the normal number of
treated patients at the linear accelerator."
    Nucletron also produces planning and treatment systems for brachytherapy,
used for the treatment of prostate and other cancers. With brachytherapy,
radioactive sources are positioned in the tumour to be treated, also giving a
highly conformal dose distribution. "Nucletron is proud of its innovations in
radiotherapy products that help fight cancer. The clinical use of PLATO's
inverse treatment planning software in Sevilla and other centres demonstrates
that these new and complex techniques can be widely used to benefit patients,"
said Rudolf Scholte, Managing Director of Nucletron.
    The Sevilla group has a large number of international scientific
publications related to Medical Physics and maintains close links and
collaborations with important European radiotherapy centres. The group has
organised several seminars and conferences. Currently they are organising a
workshop on "Verification of IMRT" that will take place in Sevilla during September 2001.