Photons, protons or carbon ions for stage I non-small cell lung cancer - results of the multicentric ROCOCO in silico study


Photons, protons or carbon ions for stage I non-small cell lung cancer - results of the multicentric ROCOCO in silico study

Wink, K. C. J.; Roelofs, E.; Simone, C. B.; Dechambre, D.; Santiago, A.; van der Stoep, J.; Dries, W.; Smits, J.; Avery, S.; Ammazzalorso, F.; Jansen, N.; Jelen, U.; Solberg, T.; de Ruysscher, D.; Troost, E. G. C.

Purpose: To compare dose to organs at risk (OARs) and dose-escalation possibility for 24 stage I nonsmall cell lung cancer (NSCLC) patients in a ROCOCO (Radiation Oncology Collaborative Comparison) trial.
Methods: For each patient, 3 photon plans [Intensity-modulated rad 5 iotherapy (IMRT), volumetric modulated arc therapy (VMAT) and CyberKnife], a double scattered proton (DSP) and an intensitymodulated carbon-ion (IMIT) therapy plan were created. Dose prescription was 60Gy (equivalent) in 8 fractions.
Results: The mean dose and dose to 2% of the clinical target volume (CTV) were lower for protons 10 and ions compared with IMRT (p<0.01). Doses to the lungs, heart, and mediastinal structures were lowest with IMIT (p<0.01), doses to the spinal cord were lowest with DSP (p<0.01). VMAT and CyberKnife allowed for reduced doses to most OARs compared with IMRT. Dose escalation was possible for 8 patients. Generally, the mediastinum was the primary dose-limiting organ.
Conclusion: On average, the doses to the OARs were lowest using particles, with more homogenous 15 CTV doses. Given the ability of VMAT and CyberKnife to limit doses to OARs compared with IMRT, the additional benefit of particles may only be clinically relevant in selected patients and thus should be carefully weighed for every individual patient.

Keywords: stage I NSCLC; radiotherapy; particle therapy; in silico planning study; multicentric trial

Permalink: https://www.hzdr.de/publications/Publ-25597
Publ.-Id: 25597