Nikoghosyan et al. BMC Cancer 2010, 10:607 http://www.biomedcentral.com/1471-2407/10/607 authors thank Daniela Schulz-Ertner for fruitful discussions about the study concept and treatment aspects and Rita Engelhardt-Cabilic for agreeing to be part of data monitoring committee. We want to thank our study nurse Renate Haselmann and case manager Rebecca Klumpp for great help in creation of case record form and logistic part of the work flow. Written consent for publication was obtained from the patient. Author details 1Dept. of Clinical Radiology, University of Heidelberg, INF 400, 69120 Heidelberg, Germany. 2Biometrics and Data Management, DKFZ G040, Patient and NCT Clinical Trial Center, Im Neuenheimer Feld 581, 69120 Heidelberg, Germany. Authors’ contributions AVN, IKS, MWM, ADJ, SEC, and JD have developed the study concept. AVN, MWM, IKS, ADJ, SEC and JD wrote the study protocol and obtained ethics approval. IKS was responsible for statistical considerations. 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Pre-publication history The pre-publication history for this paper can be accessed here: http://www.biomedcentral.com/1471-2407/10/607/prepub doi:10.1186/1471-2407-10-607 Cite this article as: Nikoghosyan et al.: Randomised trial of proton vs. carbon ion radiation therapy in patients with chordoma of the skull base, clinical phase III study HIT-1-Study. BMC Cancer 2010 10:607. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color ﬁgure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit