Benefit of particle therapy in re-irradiation of head and neck patients. Results of a multicentric in silico ROCOCO trial

Danielle B. P. Eekers*, Erik Roelofs, Urszula Jelen, Maura Kirk, Marlies Granzier, Filippo Ammazzalorso, Peter H. Ahn, Geert O. R. J. Janssens, Frank J. P. Hoebers, Tobias Friedmann, Timothy Solberg, Sean Walsh, Esther G. C. Troost, Johannes H. A. M. Kaanders, Philippe Lambin

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review


Background and Purpose: In this multicentric in silica trial we compared photon, proton, and carbon-ion radiotherapy plans for re-irradiation of patients with squamous cell carcinoma of the head and neck (HNSCC) regarding dose to tumour and doses to surrounding organs at risk (OARS). Material and Methods: Twenty-five HNSCC patients with a second new or recurrent cancer after previous irradiation (70 Gy) were included. Intensity-modulated proton therapy (IMPT) and ion therapy (IMIT) re irradiation plans to a second subsequent dose of 70 Gy were compared to photon therapy delivered with volumetric modulated arc therapy (VMAT). Results: When comparing IMIT and IMPT to VMAT, the mean dose to all investigated 22 OARs was significantly reduced for IMIT and to 15 out of 22 OARs (68%) using IMPT. The maximum dose to 2% volume (D-2) of the brainstem and spinal cord were significantly reduced using IMPT and IMIT compared to VMAT. The data are available on Conclusions: In this ROCOCO in silica trial, a reduction in mean dose to OARs was achieved using particle therapy compared to photons in the re-irradiation of HNSCC. There was a dosimetric benefit favouring carbon-ions above proton therapy. These dose reductions may potentially translate into lower severe complication rates related to the re-irradiation.
Original languageEnglish
Pages (from-to)387-394
JournalRadiotherapy and Oncology
Issue number3
Publication statusPublished - Dec 2016


  • In silico planning study
  • Head and neck
  • Re-irradiation
  • Multicentric trial
  • Radiotherapy
  • Particle therapy

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