nach oben

Erschienen in:

01.10.2014 | Original article

New possibilities for volumetric-modulated arc therapy using the Agility^TM 160-leaf multileaf collimator

verfasst von: Dipl.-Ing. Nadine Blümer, Christian Scherf, Janett Köhn, Eugen Kara, Britta Loutfi-Krauß, Detlef Imhoff, Claus Rödel, Ulla Ramm, Jörg Licher

Erschienen in: Strahlentherapie und Onkologie | Ausgabe 11/2014

Einloggen, um Zugang zu erhalten

Abstract

Purpose

This study compares the quality of intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans optimized for an Elekta Agility^TM (Elekta, Stockholm, Sweden) multileaf collimator (MLC; leaf width 5 mm) and an Elekta MLCi2 (leaf width 10 mm) for complex target volumes (anal, AC; head and neck, H&N and prostate cancer, PC).

Patients and methods

For plan comparisons, 15 patients who had been treated with IMRT or VMAT using the MLCi2 were selected. For each patient, a retrospective treatment plan using the MLCi2 for the technique not applied was created, as were treatment plans for both techniques using the Agility^TM MLC. Dose–volume histograms (DHVs) for planning target volumes (PTVs) and organs at risk (OARs) were compared. Further parameters relating to dose conformity, dose homogeneity and mean dose (D_mean) to the PTV, compliance with the intended OAR dose criteria and overall dose to normal tissue were analyzed. Verification measurements were performed and optimization and treatment times were compared.

Results

Compared to the MLCi2 plans, the Agility^TM IMRT and VMAT plans show better or equivalent results in terms of PTV dose conformity and homogeneity. Compliance with the intended OAR dose criteria does not differ according to technique or MLC type. Slight differences are shown for dose distributions in OARs and normal tissue. Verification measurements show that all plans fulfill the acceptance criteria of a minimum of 95 % matched dose points for the 3 %/3 mm γ criterion. Optimization times for the VMAT plans increase compared to the IMRT plans, whereas treatment times decrease.

Conclusion

With the MLCi2, treatment of complex target volumes with VMAT was only possible with compromises in terms of target coverage. Using the Agility^TM MLC, even complex target volumes can be treated with VMAT without compromising target coverage or resulting in higher exposure of OARs or normal tissue.

Uzel EK, Kara˛c am S, Eli˛c in O et al (2013) Comparison of two different IMRT planning techniques in the treatment of nasopharyngeal carcinoma. Strahlenther Onkol 189:552–558PubMedCrossRef

Vanetti E, Clivio A, Nicolini G et al (2009) Volumetric modulated arc radiotherapy for carcinomas of the oro-pharynx, hypo-pharynx and larynx: a treatment planning comparison with fixed field IMRT. Radiother Oncol 92:111–117PubMedCrossRef

Verbakel WFAR, Cuijpers JP, Hoffmans D et al (2009) Volumetric intensity-modulated arc therapy vs. conventional IMRT in head-and-neck cancer: a comparative planning and dosimetric study. Int J Radiat Oncol Biol Phys 74:252–259PubMedCrossRef

Wolff D, Stieler F, Welzel G et al (2009) Volumetric modulated arc therapy (VMAT) vs. serial tomotherapy, step-and-shoot IMRT and 3D-conformal RT for treatment of prostate cancer. Radiother Oncol 93:226–233PubMedCrossRef

Zhang P, Happersett L, Hunt M et al (2010) Volumetric modulated arc therapy: planning and evaluation for prostate cancer cases. Int J Radiat Oncol Biol Phys 76:1456–1462PubMedCrossRef

Lambrecht M, Nevens D, Nuyts S (2013) Intensity-modulated radiotherapy vs. parotid-sparing 3D conformal radiotherapy. Strahlenther Onkol 189:223–229PubMedCrossRef

Pasler M, Wirtz H, Lutterbach J (2011) Impact of gantry rotation time on plan quality and dosimetric verification—Volumetric modulated arc therapy (VMAT) vs. intensity modulated radiotherapy (IMRT). Strahlenther Onkol 187:812–819PubMedCrossRef

Burmeister J, McDermott PN, Bossenberger T et al (2004) Effect of MLC leaf width on the planning and delivery of SMLC IMRT using the CORVUS inverse treatment planning system. Med Phys 31:3187–3193PubMedCrossRef

Fiveash JB, Murshed H, Duan J et al (2002) Effect of multileaf collimator leaf width on physical dose distributions in the treatment of CNS and head and neck neoplasms with intensity modulated radiation therapy. Med Phys 29:1116–1119PubMedCrossRef

Nill S, Tücking T, Münter MW et al (2005) Intensity modulated radiation therapy with multileaf collimators of different leaf widths: a comparison of achievable dose distributions. Radiother Oncol 75:106–111PubMedCrossRef

Zwicker F, Hauswald H, Nill S et al (2010) New multileaf collimator with a leaf width of 5 mm improves plan quality compared to 10 mm in step-and-shoot IMRT of HNC using integrated boost procedure. Strahlenther Onkol 186:334–343PubMedCrossRef

Clivio A, Fogliata A, Franzetti-Pellanda A et al (2009) Volumetric-modulated arc radiotherapy for carcinomas of the anal canal: A treatment planning comparison with fixed field IMRT. Radiother Oncol 92:118–124PubMedCrossRef

Cozzi L, Dinshaw KA, Shrivastava SK et al (2008) A treatment planning study comparing volumetric arc modulation with RapidArc and fixed field IMRT for cervix uteri radiotherapy. Radiother Oncol 89:180–191PubMedCrossRef

Bedford JL, Thomas MDR, Smyth G (2013) Beam modeling and VMAT performance with the agility 160-leaf multileaf collimator. J Appl Clin Med Phys 14:172–185

Elekta AB: MLCi2. Product data (2009)

Elekta AB: AgilityTM high resolution beam shaping. Product data (2012)

Fraunholz I, Weiss C, Eberlein K et al (2010) Concurrent chemoradiotherapy with 5-fluorouracil and mitomycin C for invasive anal carcinoma in human immunodeficiency virus-positive patients receiving highly active antiretroviral therapy. Int J Radiat Oncol Biol Phys 76:1425–1432PubMedCrossRef

DKSR—Deutsches KrebsStudienRegister: Randomisierte Phase III-Studie zur Radiochemotherapie lokal weit fortgeschrittener Kopf-Hals-Tumoren der Stadien III und IVA-B: Reduktion der Strahlendosis im Rahmen der Radiochemotherapie (RCT) mit Paclitaxel/Cisplatin im Vergleich zu einer Standard-RCT mit 5-FU/Cisplatin. http://www.studien.de/PDF/587.pdf. Accessed 09 Apr 2013

Budach V, Stuschke M, Budach W et al (2005) Hyperfractionated accelerated chemoradiation with concurrent fluorouracil-mitomycin is more effective than dose-escalated hyperfractioned accelerated radiation therapy alone in locally advanced head and neck cancer: final results of the radiotherapy cooperative clinical trials group of the German Cancer Society 95—06 prospective randomized trial. J Clin Oncol 23:1125–1135PubMedCrossRef

Guckenberger M, Ok S, Polat B et al (2010) Toxicity after intensity-modulated, image-guided radiotherapy for prostate cancer. Strahlenther Onkol 186:535–543PubMedCrossRef

Alvarez-Moret J, Pohl F, Koelbl O et al (2010) Evaluation of volumetric modulated arc therapy (VMAT) with Oncentra MasterPlan^® for the treatment of head and neck cancer. Radiat Oncol 5:110–119PubMedCentralPubMedCrossRef

International Commission on Radiation Units and Measurements (1993) ICRU Report 50. Prescribing, recording, and reporting photon beam therapy. ICRU, Bethesda, MD

ONCENTRA v4.3 Documentation: Physics and Algorithms. (2012) Nucletron B.V., An Elekta company. Veenendaal, The Netherlands

CERR: A computational environment for radiotherapy research, V 4.0 Beta 2. http://www.cerr.info. Accessed 31 Aug 2013

Van´t Riet A, Mak, Moerland MA et al (1997) A conformation number to quantify the degree of conformality in brachytherapy and external beam irradiation: application to the prostate. Int J Radiat Oncol Biol Phys 37:731–736CrossRef

Wu Q, Mohan R, Morris M et al (2003) Simultaneous integrated boost intensity-modulated radiotherapy for locally advanced head-and-neck squamous cell carcinomas. I: Dosimetric results. Int J Radiat Oncol Biol Phys 56:573–585PubMedCrossRef

Hodapp N (2012) Der ICRU-Report 83: Verordnung, Dokumentation und Kommunikation der fluenzmodulierten Photonenstrahlentherapie (IMRT). Strahlenther Onkol 188:97–99PubMedCrossRef

International Commission on Radiation Units and Measurements. ICRU Report 83. (2010) Prescribing, recording, and reporting photon-beam intensity-modulated radiation therapy (IMRT). ICRU, Bethesda, MD

Hoogeman MS, Nuyttens JJ, Levendag PC et al (2008) Time dependence of intrafraction patient motion assessed by repeat stereoscopic imaging. Int J Radiat Oncol Biol Phys 70:609–618PubMedCrossRef

Titel: New possibilities for volumetric-modulated arc therapy using the AgilityTM 160-leaf multileaf collimator
verfasst von: Dipl.-Ing. Nadine Blümer
Christian Scherf
Janett Köhn
Eugen Kara
Britta Loutfi-Krauß
Detlef Imhoff
Claus Rödel
Ulla Ramm
Jörg Licher
Publikationsdatum: 01.10.2014
Verlag: Springer Berlin Heidelberg
Erschienen in: Strahlentherapie und Onkologie / Ausgabe 11/2014
Print ISSN: 0179-7158
Elektronische ISSN: 1439-099X
DOI: https://doi.org/10.1007/s00066-014-0692-3

Neu im Fachgebiet Onkologie

Nodal-negativ nach neoadjuvanter Chemo: Axilladissektion verzichtbar?

03.05.2024 Mammakarzinom Nachrichten

Wenn bei Mammakarzinomen durch eine neoadjuvante Chemotherapie ein Downstaging von nodal-positiv zu nodal-negativ gelingt, scheint es auch ohne Axilladissektion nur selten zu axillären Rezidiven zu kommen.

Wo hapert es noch bei der Umsetzung der POMGAT-Leitlinie?

03.05.2024 DCK 2024 Kongressbericht

Seit November 2023 gibt es evidenzbasierte Empfehlungen zum perioperativen Management bei gastrointestinalen Tumoren (POMGAT) auf S3-Niveau. Vieles wird schon entsprechend der Empfehlungen durchgeführt. Wo es im Alltag noch hapert, zeigt eine Umfrage in einem Klinikverbund.

Bestrahlung nach Prostatektomie: mehr Schaden als Nutzen?

02.05.2024 Prostatakarzinom Nachrichten

Eine adjuvante Radiotherapie nach radikaler Prostata-Op. bringt den Betroffenen wahrscheinlich keinen Vorteil. Im Gegenteil: Durch die Bestrahlung steigt offenbar das Risiko für Harn- und Stuhlinkontinenz.

Endlich: Zi zeigt, mit welchen PVS Praxen zufrieden sind

IT für Ärzte Nachrichten

Darauf haben viele Praxen gewartet: Das Zi hat eine Liste von Praxisverwaltungssystemen veröffentlicht, die von Nutzern positiv bewertet werden. Eine gute Grundlage für wechselwillige Ärzte und Psychotherapeuten.

Live-Webinar "Chronische Unterbauch- und Viszeralschmerzen in der Praxis managen"

Springer Medizin

New possibilities for volumetric-modulated arc therapy using the Agility^TM 160-leaf multileaf collimator