Randomised Trial of Proton vs. Carbon Ion Radiation Therapy in Patients With Low and Inter-mediate Grade Chondrosarcoma of the Skull Base, Clinical Phase III Study
The study is a prospective randomised clinical phase III trial. The trial will be carried
out at Heidelberger Ionenstrahl-Therapie (HIT) centre as monocentric trial.
Proton therapy is the gold standard in the treatment of low and intermediate grad
chondrosarcomas of the skull base. However, high-LET beams such as carbon ions theoretically
offer biologic advantages by enhanced biologic effectiveness in slow-growing tumors. Up
until now it was impossible to compare two different particle therapies, i.e. proton and
carbon ion therapy directly with each other. The aim of this study is to find out, whether
the biological advantages of carbon ion therapy mentioned above can also be clinically
Patients with skull base chondrosarcomas will be randomised to either proton or carbon ion
radiation therapy. As a standard, patients will undergo non-invasive, rigid immobilization
and target volume definition will be carried out based on CT and MRI data. The biologically
isoeffective target dose to the PTV in carbon ion treatment will be 60 Gy E ± 5% and 70 Gy E
± 5% (standard dose) in proton therapy respectively. The 5 year local-progression free
survival (LPFS) rate will be analysed as primary end point. Overall survival, progression
free and metastasis free survival, patterns of recurrence, local control rate and morbidity
are the secondary end points. Plan quality is also a matter of interest.
Allocation: Randomized, Endpoint Classification: Bio-equivalence Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment
Local-Progression Free Survival (LPFS)
The primary objective of this study is to evaluate, if the innovative carbon ion therapy in chondrosarcomas is not relevantly inferior to the standard proton treatment with respect to the 5 year LPFS rate defined as time from the randomisation to observed local reccurrence. It is assumed that the LPFS rate for the proton therapy is 90%.
Juergen Debus, MD PhD
University of Heidelberg
Germany: Bundesamt für Strahlenschutz