000136905 001__ 136905 000136905 005__ 20240229105106.0 000136905 0247_ $$2doi$$a10.1016/j.radonc.2017.12.031 000136905 0247_ $$2pmid$$apmid:29370987 000136905 0247_ $$2ISSN$$a0167-8140 000136905 0247_ $$2ISSN$$a1879-0887 000136905 0247_ $$2altmetric$$aaltmetric:32322009 000136905 037__ $$aDKFZ-2018-01343 000136905 041__ $$aeng 000136905 082__ $$a610 000136905 1001_ $$aUnkelbach, Jan$$b0 000136905 245__ $$aOptimization of combined proton-photon treatments. 000136905 260__ $$aAmsterdam [u.a.]$$bElsevier Science$$c2018 000136905 3367_ $$2DRIVER$$aarticle 000136905 3367_ $$2DataCite$$aOutput Types/Journal article 000136905 3367_ $$0PUB:(DE-HGF)16$$2PUB:(DE-HGF)$$aJournal Article$$bjournal$$mjournal$$s1535976867_16379 000136905 3367_ $$2BibTeX$$aARTICLE 000136905 3367_ $$2ORCID$$aJOURNAL_ARTICLE 000136905 3367_ $$00$$2EndNote$$aJournal Article 000136905 520__ $$aProton treatment slots are a limited resource. Therefore, we consider combined proton-photon treatments in which most fractions are delivered with photons and only a few with protons. We demonstrate how both modalities can be combined to optimally capitalize on the proton's ability to reduce normal tissue dose.An optimal combined treatment must account for fractionation effects. We therefore perform simultaneous optimization of intensity-modulated proton (IMPT) and photon (IMRT) plans based on their cumulative biologically effective dose (BED). We demonstrate the method for a sacral chordoma patient, in whom the gross tumor volume (GTV) abuts bowel and rectum.In an optimal combination, proton and photon fractions deliver similar doses to bowel and rectum to protect these dose-limiting normal tissues through fractionation. However, proton fractions deliver, on average, higher doses to the GTV. Thereby, the photon dose bath is reduced. An optimized 30-fraction treatment with 10 IMPT fractions achieved more than 50% of the integral dose reduction in the gastrointestinal tract that is possible with 30 IMPT fractions (compared to 33% for a simple proton-photon combination in which both modalities deliver the same target dose).A limited number of proton fractions can best be used if protons hypofractionate parts of the GTV while maintaining near-uniform fractionation in dose-limiting normal tissues. 000136905 536__ $$0G:(DE-HGF)POF3-315$$a315 - Imaging and radiooncology (POF3-315)$$cPOF3-315$$fPOF III$$x0 000136905 588__ $$aDataset connected to CrossRef, PubMed, 000136905 7001_ $$0P:(DE-He78)fec480a99b1869ec73688e95c2f0a43b$$aBangert, Mark$$b1$$udkfz 000136905 7001_ $$aDe Amorim Bernstein, Karen$$b2 000136905 7001_ $$aAndratschke, Nicolaus$$b3 000136905 7001_ $$aGuckenberger, Matthias$$b4 000136905 773__ $$0PERI:(DE-600)1500707-8$$a10.1016/j.radonc.2017.12.031$$gVol. 128, no. 1, p. 133 - 138$$n1$$p133 - 138$$tRadiotherapy and oncology$$v128$$x0167-8140$$y2018 000136905 909CO $$ooai:inrepo02.dkfz.de:136905$$pVDB 000136905 9101_ $$0I:(DE-588b)2036810-0$$6P:(DE-He78)fec480a99b1869ec73688e95c2f0a43b$$aDeutsches Krebsforschungszentrum$$b1$$kDKFZ 000136905 9131_ $$0G:(DE-HGF)POF3-315$$1G:(DE-HGF)POF3-310$$2G:(DE-HGF)POF3-300$$3G:(DE-HGF)POF3$$4G:(DE-HGF)POF$$aDE-HGF$$bGesundheit$$lKrebsforschung$$vImaging and radiooncology$$x0 000136905 9141_ $$y2018 000136905 915__ $$0StatID:(DE-HGF)0420$$2StatID$$aNationallizenz 000136905 915__ $$0StatID:(DE-HGF)0100$$2StatID$$aJCR$$bRADIOTHER ONCOL : 2015 000136905 915__ $$0StatID:(DE-HGF)0200$$2StatID$$aDBCoverage$$bSCOPUS 000136905 915__ $$0StatID:(DE-HGF)0300$$2StatID$$aDBCoverage$$bMedline 000136905 915__ $$0StatID:(DE-HGF)0310$$2StatID$$aDBCoverage$$bNCBI Molecular Biology Database 000136905 915__ $$0StatID:(DE-HGF)0600$$2StatID$$aDBCoverage$$bEbsco Academic Search 000136905 915__ $$0StatID:(DE-HGF)0030$$2StatID$$aPeer Review$$bASC 000136905 915__ $$0StatID:(DE-HGF)0199$$2StatID$$aDBCoverage$$bThomson Reuters Master Journal List 000136905 915__ $$0StatID:(DE-HGF)0110$$2StatID$$aWoS$$bScience Citation Index 000136905 915__ $$0StatID:(DE-HGF)0150$$2StatID$$aDBCoverage$$bWeb of Science Core Collection 000136905 915__ $$0StatID:(DE-HGF)0111$$2StatID$$aWoS$$bScience Citation Index Expanded 000136905 915__ $$0StatID:(DE-HGF)1110$$2StatID$$aDBCoverage$$bCurrent Contents - Clinical Medicine 000136905 915__ $$0StatID:(DE-HGF)1050$$2StatID$$aDBCoverage$$bBIOSIS Previews 000136905 915__ $$0StatID:(DE-HGF)9900$$2StatID$$aIF < 5 000136905 9201_ $$0I:(DE-He78)E040-20160331$$kE040$$lMedizinische Physik in der Strahlentherapie$$x0 000136905 980__ $$ajournal 000136905 980__ $$aVDB 000136905 980__ $$aI:(DE-He78)E040-20160331 000136905 980__ $$aUNRESTRICTED